Training Programme on
Geomatics for Coastal Zone Management (18-22, April 2016)
Kerala University of Fisheries and Ocean Studies (KUFOS) Panangad, Kochi - 682 506
Nansen Environmental Research Centre, India (NERCI), Kochi – 682 016
Ministry of Earth Sciences Integrated Coastal and Marine Area Management (ICMAM) Project Directorate, Chennai - 600 100
Page Sl. No.
1.
Lectures
No.
Concept and Application of Integrated Coastal Zone Management Dr. P. Madeswaran
2.
Geomatics for ICZM Dr. Tune Usha
2 19
Integrated study on ecosystem status of SW coast of India 3.
34 Dr. V. Ranga Rao Marine Pollution – An Overview
4.
5.
6.
7. 8 9
Dr. N R Menon Fundamentals of Remote Sensing Dr. S. K. Dash Computation of Suspended Sediment Transport in Coastal and Estuarine Waters – A Case Study Dr. K. Rasheed Hands on Session G. Gopinath & M. Iyyappan Concepts and Policies of ICZM
Dr.K.Ajith Joseph
Coastal Processes, Coastal Erosion, and Application along Indian Coast
48
53
62
71 101 109
Dr.K.V.Thomas 10
Technical programme sheet
116
Acknowledgement: The organisers wish to express their sincere gratitude to Kerala State Council for Science Technology and Environment (KSCSTE), Government of Kerala, for the financial support received for publishing this training manual and course materials for the Training programme and workshop on Geomatics for Coastal Zone Management.
CONCEPT AND APPLICATION OF INTEGRATED COASTAL ZONE MANAGEMENT Dr. P.Madeswaran Scientist-F Ministry of Earth Sciences ICMAM - Project Directorate, Chennai 600100 Email:
[email protected] 1.0
Introduction Integrated Coastal Zone Management (ICZM), is an adaptive process of resources
management for sustainable development in coastal and marine areas. In other words, it is a process of governance and consists of the legal and institutional framework necessary to ensure that development and management are integrated with environmental (including social) goals and are made with the participation of those effected. The management issues are based on scientific knowledge derived from several scientific investigations on coastal habitats as well as coastal and oceanic processes. 2.0 Need for Integrated Management Clearly, it is becoming more and more difficult to manage any one particular coastal natural resources or enhance one economic sector in the absence of a comprehensive, integrated, framework for policy planning and management. The overall objective of an integrated management programme, like ICZM, is to provide for the best long-term and sustainable use of coastal natural resources and for perpetual maintenance of the most beneficial natural environment. ICZM incorporates modern principles of planning and resources management, intensive information bases and interdisciplinary process. It has proved to be an effective general framework for dealing with conflicts arising from interactions of the various uses of coastal areas. It aims at coordinated development and resources management. For ICZM to succeed, a broad context of government and interest group involvement is essential. Fishing, mining, shipping, defence, public health, and recreation are complex activities requiring cooperative management and intersectoral coordination. To accomplish the coordination requires the full involvement of all the various stakeholders through an ICZM comprehensive and integrated programme.
2
3.0
Benefits of ICZM ICZM programmes can: 1) minimize costly delays in project implementation;
2) minimize damage to the marine environment and its resources; 3) minimize losses to the various users (from resource depletion, access limitations, etc.); 4) make the most efficient use of infrastructure, information and technology available to marine development sectors; and 5) avoids conflicting use of coastal and marine environment.
4.0. Activities, their inter-relationship and approach for integrated Management Several examples can be given to show the impact of one activity on the other. For example, the increasing of population leads to generation of domestic sewage and industrial growth due to need for employment. The wastes from domestic and industrial sources which vary in quantity and quality with time, pose serious threat to coastal ecology as well as fisheries. The fish species are normally dependent upon certain specific species for feeding and increase of pollution may lead to either disappearance of the food species or succeeded by another species which will be resistant to pollution. The succeeded species may not be preferred as a food to the fish which ultimately leads to reduction in number of the fish species.Such similar impacts can occur due to changes in catchment areas of rivers. Construction of barrages and diversion of freshwater leads to reduced flow of freshwater in rivers which alters the salinity in estuaries. A few fish species are salinity dependent for their breeding and spawning. Such reduction in freshwater flow also affects the coastal aquifers. Excessive drawl of ground water leads to intrusion of salt water and it is needless to say about these impacts. Similarly accretion and erosion due to deepening of navigational channels is common is harbour areas. Loss of beach areas affect tourism and it reduces land area available for fish landing centres.
Therefore, it is necessary to adopt guidelines while determining sectoral policies i.e., policies and actions for the development of individual sectors.
Some of these guidelines
are: •
Urban growth should be co-ordinated with the available capacity of the infrastructure: uses should not be permitted beyond the absorbing capacity of available services.
3
•
The location and operation of industrial facilities should be controlled to prevent adverse impacts on tourism and on natural resources, and be required to incorporate measures for the prevention or abatement of water, land, air and noise pollution.
•
Tourism should be integrated with policies for development with nature and landscape protection, in a way which contributes, through revenue generation, to the protection and improvement of the very environment which attracts visitors.
•
Areas for aquaculture should be allocated with due consideration to other coastal activities and to existing or possible discharges to marine waters
•
Facilities for fishing should be maintained, with appropriate controls for the protection of fish stocks and of marine nature reserves
•
Coastal agricultural use should be maintained not only for food production and employment but also for landscape management and as a valid use of open space for the purpose of separating urban centres and preventing continuous development along the shore
•
Open spaces should be maintained to separate urban centres and to ensure the protection of natural and landscape coastal resources.
•
Development should not be permitted to encroach on the shoreline; the immediate coastal strip (whose width will vary according to natural conditions and to social and economic requirements) should remain free of construction and recognised as far as possible as rightfully open to public access.
5.0. Development and Implementation of ICZM 5.1. Approaches to ICZM Most examples of ICZM to date have been generated at central government level, taking responsibility for marine and coastal resources for society as a whole. It is a top-down approach which, to be successfully implemented, requires the cooperation of State Government and local coastal communities. Even where a government-sponsored approach is adopted, the intrinsic nature of ICZM requires the active involvement of local communities and stakeholders, bringing the top-down and bottom-up approaches together in a synergistic framework.
Though ICZM is in many cases a government sponsored, long term process, the private sector should play an important role in furthering sustainable development in the 4
coastal region.
Private investment can be harnessed with incentives as necessary, to
contribute to implementing appropriate development programmes in accordance with ICZM whereas inappropriate short term private investment should be deterred.
5.1.1 Types of ICZM Plans The ICZM plans are of two major types: i. Area based ii. Activity based Application of ICZM for an activities depends on magnitude of the problem to be solved. In case of a large scale problem of resource depletion which causes major livelihood problems to dependent population, a large scale integrated resource management plan containing details of strategies developed to control resource exploitation and also augmentation of resources using a variety of methods should be in place. Normally such applications are more suited for large rural areas where other coastal related activities are minimal and excellently source controlled. In contrast, mostly throughout the world an area management plan is preferred, as prevailing activities and their future plans could be optimally integrated so that all activities are sustained to optimal/acceptable levels.
5.2. Stages of the ICZM process In coastal areas, where accommodation to rapid change is often required, flexible decision making calls for a continuous process of planning, implementation and goaladjustment. In resource management process, such as ICZM decisions are being taken in three separate stages: initiation, planning and implementation.
Initiation of ICZM includes the analysis of triggering factors which could strengthen public awareness of coastal issues and the need to take actions in coastal areas to solve issues/problems Planning in ICZM refers to the development of policies and goals, and selection of concrete sets of actions (strategies) to produce the desired mix of goods and services from the coastal area over time.
It is a goal-directed decision-making process involving the ability to
anticipate future events, a capability for analyzing and evaluating situations, and a capacity for innovative thinking to derive satisfactory solutions.Implementation is the vehicle through which the plan is put into effect. It is the process of operational decision-making, 5
working towards the objectives of the plan through interaction with relevant administrative, legal, financial and social structures, and with the public participation. These three stages of ICZM contain the following phases: *
Initiation: initiation of ICZM;
*
Planning: preparatory phase; analysis and forecasting; definition of goals, development strategies and
*
Implementation: implementation of plans; monitoring and evaluation.
The management process requires that its phases be cyclically repeated. The results of the operative phases are constantly monitored, and the links between various phases include feedback mechanisms ensuring timely correction of activities which, on the basis of monitoring and evaluation, may have taken a wrong direction. Preparation for the initiation of the ICZM process necessitates some prerequisites to be met. Of particular importance are the following ones: *
Political will and public (including NGOs and scientific institutions) awareness;
*
Scientifically based knowledge of the coastal and marine ecosystems;
*
Existence of global national strategies;
*
Recognition of the value of coastal and marine resources and potential benefits from sustainable management;
*
Management capability and adequate human resources;
*
Financial support.
5.3. Preparatory phase of the planning stage The purpose of this phase is to identify and support a proposal to decision-makers to establish continuous and integrated management of the coastal and marine area. The first task to be performed within this phase is to prepare a coastal profile. Based on the existing secondary data, a coastal profile helps to identify the coastal resources, activities, uses of habitats and protected areas, as well as major resources management issues such as open access to coastal resources, multi-purpose use, development patterns, user conflicts and specific priorities for management in a coastal area. The existing data often have to be complemented with a questionnaire containing questions on all relevant aspects of development and environment of coastal areas. Questionnaires have to be filled out together by local and national experts. 6
The second task, to be performed using the coastal profile and inputs from various sectors and interest groups, is to prepare an ICZM programme, which is a problem-oriented document consisting of the following: *
Precise definition of the coastal area, i.e. the area boundaries (for example, in the case of areas covering the totality of a national coastline it is desirable to include the relevant drainage basins and the national maritime exclusive economic zone; in the case of smaller island states, the inclusion of the whole national territory is advantageous);
*
Identification of the major problems/issues of the area and their causes (sector by sector with emphasis on problems requiring cross-sectoral solutions);
*
Proposal of the general goals and objectives of development and environmental protection; preparation of development outlooks and tentative strategies for their achievement; analysis of the social and economic implications of the strategies proposed;
*
Identification of information gaps;
*
Analysis of ongoing planning programmes and project activities, with the assessment of their impacts on the coastal area and in relation to their relevance for ICZM activities;
*
Proposal for the preparation of the ICZM Plan;
*
Analysis of legal requirements posed by the proposal (e.g. a need for new legislation or for changes in existing legislation);
*
Analysis of the financial requirements of the implementation of ICZM; and
*
Proposal of institutional arrangements needed to support the coordination and implementation of ICZM. The scale of the maps to be used for the preparation of the coastal profile and ICZM
programme is very important. it is determined by the scale of the maps available with the relevant departments. One has to adapt to the actual situation since these phases of ICZM do not envisage preparation of new maps. The scales can vary considerably, as given below: *
national level:
1 : 200,000
*
sub-national regional level
1 : 200,000 - 1 : 50,000
*
urban level
1 : 50,000 - 1 : 10,000
*
site level
1 : 10,000 - 1 : 1,000 7
The ICZM programme, including the proposal of future activities, should be reviewed and the decision on the ICZM process made.
5.4. Analysis and forecasting Following the preparatory stage and once the decision to establish ICZM has been made, a far more detailed stage of analysis is to be carried out. The purpose of this phase is to provide an analytical basis for the establishment of precise goals and objectives and definition of management strategies for sustainable development in the coastal area. However, this phase is strongly issue-oriented as the research is mostly aimed at the problems identified in the previous phase. In this phase it is necessary: -
to carry out new surveys in order to identify selected issues within sectors of human and economic activities, natural system processes and institutional
arrangements; -
to analyse the natural systems in the coastal and marine area;
-
to analyse the system of human and economic activities in the coastal and
marine area; -
to estimate (forecast) future demand for goods and services from coastal
resources and their capacity to fulfill these requirements; -
to prepare alternative cross-sectoral scenarios and to select the most effective one.
5.5. Definition of goals and strategies This is one of the most important phases of the whole ICZM process.
Before
proceeding further, decision-making bodies at the highest level have to approve the goals and strategies of environmentally sustainable development in the coastal area concerned. This phase consists of several steps:
-
Refinement and adoption of goals and objectives;
-
Preparation of alternative strategies; and
-
Evaluation of and decision on the most suitable strategy.
Goals may be defined as general development and environmental guidelines which should be followed in the course of the ICZM process. Goals can be grouped under a number 8
of compatible objectives. The objectives should be operational in a quantitative form where possible and should be short-term compared with the longer-term time horizon of the goals. Goals can be divided into three categories: global, area-specific and sectoral.
Area specific goals are also of a multi-sectoral nature, but are defined with regard to the specific conditions prevailing in smaller geographic areas. For example, an area with relatively undeveloped coastline may set, as one of its goals, the development of new facilities by encouring investment in tourist centres. Contrary to that a area with a highly congested coastline may set a goal of restricting the expansion of tourist and recreation facilities to existing centres. Sectoral goals refer to issues within a single development or environmental sector which is based on the use of the abundant natural resources such as tourism, fisheries, aquaculture, agriculture etc., giving priority over other sectors. All goals must be complementary and arranged in a hierarchy.
The next
step in the implementation of this phase of the ICZM process is the
development on the basis of the goals and objectives defined by relevant governmental levels of coastal and marine area management policies. In this phase, it is necessary to coordinate various aspects of individual sectoral policies to avoid policy conflicts, which often cause environmental problems in coastal areas.
The most important element of coastal area
management policies is political commitment to see the policies translated into action.
The objective of the next step in this phase of the ICZM process is the integration of sectoral and cross-sectoral management strategies in the form of sub-plans. This step is based on the existence of a high level of inter-dependence among these strategies and on the need for their implementation in a coordinated way. A typical integrated strategy should pay attention to the impact of current sectoral activities on other sectors, pattern of future activities in the area and indicate the intended changes in the physical, economic, social and environmental life of the coastal area as a result of the implementation of desired activities.
In most cases alternative strategies could be generated where impact on other sectors is significant especially on socio-economic sector where tradeoff is also discounted due to strong impacts on livelihood practices of the local populations. When strategies are evaluated and one is chosen for presentation to decision makers the strategy should include a definition 9
of criteria (qualitative) and standards (quantitative). Criteria and standards would permit the use of coastal resources within limits designed to protect them from irreversible damage. However, the standards may change over time as public awareness of environmental quality increases. The criteria represent the factors which the decision makers and other interested groups consider relevant for the evaluation of usefulness and the later adoption of a strategy. The sustainability of coastal area development should provide the fundamental criteria for the selection of strategies. The final output of this phase is a document which may be called Management strategy or Strategic plan . It consists of major dimensions such as: future population growth economic structure social patterns basic land and sea use major infrastructure systems environmentally sensitive areas conservation requirements priorities institutional structure legal and financial requirements
This document is intended for the use by decision-makers with the aim of final acceptance of the coastal area management strategy which will serve as the basis for the preparation of the Integrated Coastal Zone Management plan in the next phase of the ICZM process.
5.6. Integration of Sectoral Plans The document to be completed in this phase is the Integrated Coastal Zone Management Plan (ICZMP).
It is a complex document which requires considerable
institutional and financial resources. The objective of the ICZMP is to create conditions for making operational decisions in the implementation phase of ICZM relative to the realisation of the concept of sustainable development of coastal areas. By its nature, the ICZMP is a document which offers a very wide perspective and which contains long-term solutions to 10
the problems of coastal and marine areas. ICZMP specifies a course of action for interested persons, decision makers and professionals in the field in their performing of daily management duties. However, uncertainty increases as the perspective of the plan widens and the time horizon lengthens and the possibility increases of the operative decision-makers being forced to deviate from the plan. It is possible to overcome this problem by introducing flexibility into the planning process, so that the institutions entrusted with its implementation can respond through monitoring and feed back, to the changes in the planning context.
The principal task in this phase is to analyse cross sectoral impacts of solutions suggested in each sector to overcome the problems/issues using tools like Decision Support Systems (DSS) and detailed elaboration of the selected strategies that have least or acceptable cross-sectional impacts. ICZMP.
Then the entire sub-plans are integrated and developed as an
This will be followed by preparation of an ICZM Plan management strategy
encompassing all integrated management solutions developed for each sector. Where relevant methods like marine spatial planning can also be used to allocate the compatible or adjusted activities to ensure sustenance of activities of all the sectors. The ICZMP should include the definition of physical requirements that the implementation of the integrated management strategy may generate in the ICZM area and the preparation of the plan of action by which this strategy could be implemented. This should include detailed site-specific proposals for land and sea use based on detailed plans for prioritised areas, where sectoral policies and programmes of action related document should pay particular attention to the points given below:
I)
System of urban and rural centres (boundaries of built-up areas, main economic and social functions, distribution of population, service areas, social facilities)
ii)
Protected areas (natural areas, national parks, environmentally sensitive areas, marine habitats, cultural sites, historical and archeological sites)
iii)
Open spaces (protected natural areas, national parks, landscape reserves, coastal reserves);
iv)
Agricultural land (areas and sectors capable of expansion, permitted change from agriculture to other uses, protected agricultural land, irrigated land)
v)
Forestry (areas of wood production, grazing and recreational uses) 11
vi)
Mining (potentially exploitable areas which would not cause environmental damage)
vii)
Industrial areas ( areas where industry may be permitted, expected expansion of existing industries, additions of new industries, restrictions on polluting industries)
viii)
Residential areas (major built-up areas, standards)
ix)
Tourism and recreational areas (centres and areas allocated for the development, areas of highly restricted development, accompanying recreational areas)
x)
Sea uses ( transport facilities, shipping lanes, fishing areas, mariculture, recreation, marine protection)
xi)
Transport corridors and areas ( road network, accessibility and hierarchy of network; railway network, inter and intra-urban network, interrelationship With the
proposed road network; airports; international, domestic,
charter, agricultural, cargo; telecommunications: location of aerials, cable network) xii)
Other infrastructure (electricity network: location of power stations and sources of fuel, main transmission corridors, transformation stations, nonconventional sources of energy; water supply: reservoirs, pipes, sewerage system; oil refineries: storage and pipelines; irrigation system)
In addition, the ICZMP should outline the basis administrative framework which the plan requires for its implementation, and which is already broadly defined within the ICZM framework. The ICZMP should include those aspects of the proposed policies which can be implemented by existing laws and regulations, as well as those requiring new legislation and the agencies which will play a key part in the process. The ICZMP will also meet the need to: •
establish the procedures envisaged for the approval and the periodic revision of the plan where the strategies proposed have not yielded desired results and revision of strategy which is normally referred as adaptive management;
•
identify the authorities which will adopt the planning policies and introduce the planning controls into their operations; 12
•
define expenditure priorities and the technical personnel required to implement the plan
ascertain how the required ‘development control’ system will operate in
principle and the extent to which this system exists
(establishment of EIA
procedure, cost-benefit analysis etc.) •
ascertain the form of instruments proposed, such as building permits, planning permissions, industrial licenses, zoning regulations, development briefs, design directives etc.,
•
identify the legal basis and if possible, the administrative body which will Exercise these controls;
•
ascertain the powers available to public agencies or corporations for compulsory land acquisition, land banking, land lease and the practice followed in land valuation in cases of public land acquisition and restriction of private development rights for plan implementation purposes;
•
ascertain the financial institutions which are expected to become actively involved in mobilising funds for projects, local budgetary process, the revenue and expenditure structures, and possibly avenues for private-public joint ventures and indicate the likely impact of the implementation measures on
the existing structure of financial
institutions and processes; •
specify the instruments to be used in the plan implementation
5.7. Implementation of plans The proposals defined in the ICZMP should be formally adopted at an appropriate governmental level. An adopted plan should have legal status and the solutions and policies should be implemented in a well coordinated way. In coastal areas, a coordinating body takes the leading role in the plan implementation.
The plan implementation is most efficient if implementation phases are defined. This phasing is essentially a break-down of the ICMP proposals which usually cover periods of up to 20 years into short, medium and long term targets to arrive at a series of operational programmes fitting into identifiable 3-5 year periods over which detailed project planning, resource management and forward budgeting can be prepared and executed. In this way, the overall plan for the whole planning area, becomes implementable through specific activities in priority locations. 13
The first stage should be sufficiently self-contained to form a clear scenario of viable and specific actions but conceptually well integrated into the overall ICAM process and logically connected with the stage. The same relationship should be
designed to tran-
slate the long-term strategy into specific actions and locations, and to be carried out within the a rolling programme where five-year objectives and annual targets follow on continuously. To implement the process, it should be broken into smaller, manageable tasks or investment projects within the resources and adaptive ability of the administrative system, the budgeting process and the public at large. This offers much more scope for flexibility and adaptability as smaller components of the proposed plan can be manipulated much more easily than the overall strategy. An important advantage of phasing is the minimization of risk and of uncertainty in the planning process. Phasing reduces the element of uncertainty of implementation process by bringing long-range goals into closer perspective and limiting the range of time over which specific planning objectives are expected to be reached. Of great importance in this phase is the application of instruments to determine the environmental effects of the plans and projects defined by ICZMP. It is particularly recommended that environmental Impact Assessment (EIA) and Cost-Benefit Analysis (CBA) be included in the process of ICZMP implementation.
5.8. Monitoring and Evaluation Monitoring and evaluation of ICZM implementation are both broadly concerned with the assessment of the performance of the ICZM policies and the results achieved by ICZM over the years, relative to the goals and objectives of the ICZM process. The monitoring or “watchdog” part of the ICZM process must establish a regular flow of information on the decisions, actions and investments involved in the implementation of the ICZM. Evaluation uses the information generated by continuous monitoring to analyze: *
the effectiveness of ICZM decisions,
*
the efficiency of the investments undertaken,
*
whether the benefits of the ICZM process have been equitably distributed among the various social groups of the community; and the impacts of ICZM actions on the environment.
14
Monitoring and evaluation procedures are crucial to the ICZM process as they must systematically feed information back into the process.
This will allow for continuous
revision and up-dating of goals and objectives in the light of actual performance, effectively securing continuity and integration in the ICZM process. The implementation process should be under constant review to allow for necessary adjustments to the policies in the light of changing conditions. There is a limit to the flexibility of any process, and there is always a stage in the implementation process after which further changes are difficult to accommodate without high costs. It is, therefore, crucial that continuous evaluation is made of the costs and benefits likely to derive from adjustments to planning and implementation objectives.
5.9. Institutional, legal and financial arrangements for ICZM Given the highly complex economic structure of coastal areas and their unique and often fragile environment, special arrangements are needed for their efficient management. These arrangements consist of an administrative structure, a legal framework, a financing mechanism and policy instruments for implementation.
Institutional Arrangements One of the most frequent constraints on achieving ICZM is the lack of appropriate institutional arrangements.
Due to its complex nature, ICZM requires a high level of
integration within and between institutional structures. A high level of horizontal integration is particularly necessary between sectoral institutions at the planning stage and a high level of vertical integration is necessary within institutions at the implementation stage. Many of the institutions needed for ICZM may well exist. The linkages between them may have to be created or strengthened. Where no such institutions exist, a new institutional arrangement may need to be created. Existing institutional structures may be composed of government and local authority representatives. The successful achievement of ICZM will require the active participation of stakeholders in the public and the private sector in many of the institutional arrangements. This generates the need for building human resource capacity for ICZM both in the fields of coastal and marine sciences and in the fields of environmental management and conflict resolution.
15
Institutions for ICZM have three roles: *
An executive role, for decision making;
*
A judicial role, for enacting regulations and directives, standards and procedure enforcement and arbitration;
*
A market role, allocating funds, offering incentives or subsidies
Institutional arrangements are needed at three different levels for taking specific responsibility for coastal arrangements: *
National,
*
Regional (sub-national),
*
Coastal area (local)
National level administration should be concerned with development and implementation of broad coastal management policy; this would include preparation of a Coastal Marine Area Management Act or ICZM Act or similar, a Coastal Marine Area Management Strategy, and designation of a lead agency for coastal management at the national level. Detailed planning, development and implementation takes place at the local level. However, distinction should be made here between areas where one local government authority can effectively management the coastal zone and those areas where several local governments need to cooperate closely to plan and implement policy. To cover all land resources and coastal waters all authorities involved in the operation, exploitation, conservation and maintenance in these resources should integrate their activities within a coordinating mechanism, for example an ICZM Committee. Such a committee might be established on a voluntary or on a statutory basis. It should meet regularly and could have the following functions in guiding the ICZM process; review major development proposals, take decisions on these proposals, define the functions of the participating bodies in the decision making process and ensure public involvement, and assist in revenue raising and allocation of funds.
Coastal managers at the ICZM Committee level
would have to ensure the creation and the effective operation of such committees. They would have to be fully acquainted with national and regional coastal management policies and operations and use them for the operation of their committees. They would have to ensure that all the above functions of the coastal area management committee are carried out according to specific guidelines and sequence. Whatever the institutional arrangements, a manager will be needed to fulfill a central role in setting-up and running the committee and its various groups. 16
Legal arrangements Legal arrangements are needed at different levels to make ICZM possible. Many countries enacted a Coastal Area Management /ICZM Act which sets out various institutional arrangements, property rights, user rights, access to judicial process, right of the public to intervene in the management process, and even financing mechanism for coastal planning. At the same time many other acts and regulations are in force in coastal areas dealing with a variety of activities: shipping, fisheries, general environmental, conservation, transport and local government laws, etc. some of these laws are often dated and they can be contradictory, particularly in their interpretation. Often there is little guidance in these laws as to their order of precedence. For coastal managers one of the main tasks is to ensure an interpretation of the various laws and regulations on coastal areas and activities that will facilitate the use of coastal resources without infringing environmental and conservation legislation. This should be achieved through negotiations in the coastal management committee. Should this fail recourse might have to be taken via the judicial process or other arbitration procedure. Coastal managers might also have to take the initiative to demonstrate the need for specific and special environmental standards for certain coastal regions where circumstances would require them. Coastal managers, for example, can assist local authorities in devising regulations on such matters as property rights in beach areas, access to the coastal strip, or minimum distance of buildings from the shore, when these are not specified in national legislation.
5.10. Financing Mechanism Three types of financing requirements are generally essential for effective ICZM: financing of the administrative structure, the planning, the information system and the project review mechanism; financing the infrastructure and pollution control expenditures; and financing of conservation measures. Depending on the objective of expenditures, the financing mechanism will be different, so that: •
to finance the administrative structure and related expenditures the money will have to come from the budgets of national, regional and local authorities;
•
to finance infrastructure and pollution control, moneys can be largely generated from user charges and costs can be partially passed on to industry (user charges and similar financing instruments are described in Chapter 4 under implementation instruments); 17
•
financing of conservation of reserved areas can be undertaken partly from private voluntary financing and partly from visitors’ fees, etc..
•
Concerning funding from the various budgets, they should try to ensure that funding requirements be incorporated into the respective legislation/ regular planning processes; otherwise, the agency most interested in the proper management of the coast might have to provide the financing;
•
Concerning user charges and similar financing instruments, the manager will have to rely on them for the efficient implementation of measures as well as for financing; consequently he/she will be advocating and using them as part of the implementation process in conjunction with local authorities and other agencies. Part of his task will be to secure these funds for the installation of infrastructure and other services and minimize the amounts that are paid into general revenue and lost to coastal management;
•
Raising funds for conservation to set land aside in perpetuity is now a fairly common practice; private funds are often raised by interested environmental groups and their efforts are supported in various ways by coastal managers; for example private fund raisers usually need the assistance of the managers to establish under what conditions their efforts would be approved by the authorities; sometimes these funds are raised as matching funds (partly private and partly public). Conservation could be financed and maintained from visitor’s fees in the cases of unique sites or animal reservations, etc.
18
Geomatics for Coastal Disaster Management (ICZM) Dr. Tune Usha Scientist-F Ministry of Earth Sciences ICMAM - Project Directorate, Chennai 600 100
[email protected] 1.0 Introduction
Coastal disaster management includes mitigation, preparedness, relief, response, recovery, and reconstruction and therefore is as an important factor of sustainable economic development and better quality of civil life. An event or hazard is termed a disaster when it threatens life and property else they are simply interesting geological or meteorological phenomena. The World Health Organization (WHO) defines a disaster as ‘A severe disruption, ecological and psychological, which greatly exceeds the coping capacity of the affected community’. India is one of the most disaster prone countries in the World due to its geo-climatic conditions; according to the Vulnerability Atlas of India, 59% of land is vulnerable to Earthquakes, 8.5% of land vulnerable to Cyclones and 5% of land vulnerable to Floods with over 1 million houses damaged annually due to these hazards. India faced the onslaught of the Orissa super cyclone in 1999, cyclone Nisha in 2008, Laila in 2010 but the year 2004 was witness to one of the greatest tragedies of humankind, which wiped out many parts of South East Asia including Southern India and the Andaman and Nicobar islands. The December 26th, 2004 Sumatra tsunami caught both the people and the government unawares since it was believed that the vulnerability of the Indian coast to a tsunami hazard was quite low, until proven otherwise on the fateful day.
2.0 Emerging technologies In this respect, the awareness of new geospatial technologies and their successful utilization in disaster management is becoming crucial. Geomatics (also known as geospatial technology or geomatics engineering) is the discipline of gathering, storing, processing, and delivering geographic information, or spatially referenced information. Geomatics is relatively new as a scientific term and was coined by Dubuisson in the year 1969 by combining the terms geodesy and geoinformatics. It includes the tools and 19
techniques used in land surveying, geography, remote sensing, cartography, Geographic Information Systems (GIS), Global Navigation Satellite Systems and photogrammetry. The rapid progress and increased visibility of geomatics since 1990s has been made possible by advances in computer hardware and software and airborne and space observation remote sensing technologies. Disaster Informatics is the study of the use of spatial information and technology in the preparation, mitigation, response and recovery phases of disasters and other emergencies. It began to emerge as a ield after the successful use of a spatial technologies in recent disasters including the 2004 Tsunami, Hurricane Katrina etc. Geomatics along with numerical models have been used extensively to study and identify the coastal areas vulnerable to coastal hazards such as Tsunami, storm surges, oil spill, coastal erosion etc (Fig.1).
Fig.1. Applications of Geomatics in Coastal disaster management
2.1 Geomatics – The common tools
Today, Remote Sensing and GIS are today being used extensively world over for mapping of coastal areas especially prone for coastal disasters. Remote sensing data offers spatial data varying temporally and GIS offers the capability to analyse both spatial and aspatial data and to display the results spatially. Remote sensing and geographic information system (GIS) technologies were initially developed for different purposes. 20
However, both systems can provide information about the earth's resources. Advancements in computer hardware and software technology now make it possible for data from these sources to be easily integrated. Most GIS software packages allow remotely sensed data to be imported, or at least to be viewed within the software application. This ability allows the analyst to overlay remote sensing data layers with other spatial data layers. Analysts use remotely sensed imagery with GIS data sets for a variety of reasons, including providing a continuous regional view and extracting GIS data layers, such as contours, creation of DTM etc.
2.2 Remote Sensing
Remote sensing is the science of gathering information from a distance. Human vision is a form of optical remote sensing, as listening is a form of acoustical remote sensing. Remote sensing makes use of a wide variety of media and technologies. For instance, film photography is a form of optical remote sensing that uses photosensitive chemicals to form an image, while radar is a type of remote sensing that uses reflected radio energy to determine the distance, shape, and texture of objects. Most satellite imaging systems use electronic sensors instead of film and can broadcast the image data back for real time viewing and analysis. Eyes, ears, film, and most satellite systems are considered "passive" systems since they rely upon other sources of energy (sunlight, temperature, etc.) to produce their sensory reaction. In contrast, active systems, such as radar and sonar, actively broadcast their own energy and derive information from its reflection and scattering. Satellite remote sensing is generally used to measure or obtain information about relatively large areas such as large weather systems or county to continental-scale images and maps. Aerial photography and other airborne sensors, on the other hand, are generally used to map and measure relatively small areas in greater detail.
A few of the environmental applications of data derived from remote sensing include descriptions of current weather conditions, growth of urban or other developed landscapes, the status of wetlands habitat, coastal erosion processes, the location of oil spills, and the presence and extent of sea grass beds (Fig.2). Remote sensing can be particularly valuable for assessing relatively large areas or observing inaccessible areas. 21
Ocean feature, such as large-scale circulation patterns, currents, river turbidity, and water quality can be visualized by highlighting variations in color and temperature. Use of remote sensing techniques are becoming increasingly accessible and cost-effective due to the rapid advancements in desktop computer technology, information networks, and improved availability of remotely sensed data and information. Today, remote sensing products can map areas to a spatial accuracy of less than 1m. In general, the reasons for why remote sensing can play a major role in coastal zone studies are: remote sensing makes it possible to overcome the difficulties associated with obtaining information on natural resources and the environment, quickly, at little cost and in inaccessible places; and it can begin to provide necessary baseline information for coastal and marine environments. The spatial resolution has improved and reached a level at which the quality of public available space-borne imagery challenges that of air-borne imagery for the first time. Following figure illustrates the relationship between spatial resolution, temporal resolution and the different parameters required for coastal zone management.
Fig 2: Temporal and Spatial resolution requirements for remote observations of coastal/ocean features
There are three basic qualities inherent to remote sensing data, ‘spatial resolution’, ‘temporal resolution’ and ‘spectral resolution’. The identification of land-use or landcover patterns is usually done on a medium or large spatial scale and does not require remote sensing data with a high spatial resolution. Sequential remote sensing with very 22
high spatial resolution can be used to view whether a mangrove forest or a coral reef is dynamic or static and whether or not it has degraded. The spectral resolution depends on the study topic. High spectral qualities on the other hand, may allow the assessment of the health of individual trees through their photosynthetic or water relation properties. The temporal resolution depends on whether the study is momentary or aims at monitoring the changes in land-cover over time. The highest temporal resolution of 1 per day, in combination with high spatial and spectral resolutions, may be required to continuously monitor catastrophic phenomena such as volcanic eruptions, oil pollution, forest fires, weather events and even nuclear disasters Lower temporal resolutions serve the study of ‘before–after’-effects
2.3 Geographical Information System
On the walls of caves near Lascaux, France, Cro-Magnon hunters drew pictures of the animals they hunted 35,000 years ago (Fig.3). Associated with the animal drawings are track lines and tallies thought to depict migration followed
routes.
These
the two-element
early
records
structure of
modern geographic information systems: a graphic file linked to an attribute database.
Fig 3: Cave Paintings in Lascaux caves, France
Today, biologists use collar transmitters and satellite receivers to track the migration routes of caribou and polar bears to help design programs to protect the animals. The concepts of GIS are not new. The spatial overlay analysis available in the present day GIS software were practised way back in 1854 when maps showing the locations of the water pump and the incidence of cholera related death were studied together to locate the outbreak of the deadly disease in London.
Geographic information systems have emerged in the last decade as an essential tool for urban and resource planning and management. Their capacity to store, retrieve, analyse, 23
model and map large areas with huge volumes of spatial data has led to an extraordinary proliferation of applications. Geographic information systems are now used for land use planning, utilities management, ecosystems modelling, landscape assessment and planning, transportation and infrastructure planning, market analysis, visual impact analysis, facilities management, tax assessment, real estate analysis and many other applications. Functions of GIS include: data entry,
data
display,
management,
data
information
retrieval and analysis. A more comprehensive and easy way to define GIS is the one that looks at the disposition, in layers (Fig. 4), of its data sets. "Group of maps of the same portion of the territory, where a given location has the same coordinates in all the maps included in the system". This way, it is possible to analyse its thematic
and
spatial
characteristics to obtain a better knowledge of this zone. A few applications
of
GIS
include Fig. 4 The concept of layers (ESRI)
mapping locations, quantities, densities, finding distances and
mapping and
monitoring changes.
2.4 Global Positioning System
GPS, or the Global Positioning System, is a satellite navigation system that provides positioning and clock time to the terrestrial user (Fig.5). The system consists of more than just satellites. While the satellites make up the space segment, the system also includes a control segment that monitors and maintains the satellites, as well as the user segment. GPS was the brainchild of U.S. Department of Defense and NAVSTAR (NAVigational 24
System Time And Ranging) became the first GPS constellation. The Russian GLObal NAvigation Satellite System (GLONASS) was in use by only the Russian military, until it was made fully available to civilians in 2007. There are also the planned European Union Galileo positioning system, Chinese Compass navigation system, and Indian Regional Navigational Satellite System.
Fig. 5: Schematic of a GPS A GPS receiver calculates its position by precisely timing the signals sent by GPS satellites high above the Earth. Each satellite continually transmits messages that include •
the time the message was transmitted
•
precise orbital information (the ephemeris)
•
the general system health and rough orbits of all GPS satellites (the almanac).
The receiver uses the messages it receives to determine the transit time of each message and computes the distance to each satellite. Three satellites might seem enough to solve for position since space has three dimensions and a position near the Earth's surface can be assumed. However, even a very small clock error multiplied by the very large speed of light, the speed at which satellite signals propagate and results in a large positional error. Therefore receivers use four or more satellites to solve for the receiver's location and time. 3.0 Geomatics for coastal disaster management 3.1 Tsunami hazard maps for the Indian Coast
25
Southern India and particularly Tamil Nadu suffered large scale devastation due to the December 26th, 2004 tsunami and mitigation efforts were severely hampered due to non availability of proper tsunami vulnerability maps. Following the disastrous tsunami in the Indian Ocean, the Ministry of Earth Sciences has set up the state-of-the-art early Tsunami warning centre at INCOIS, Hyderabad with all the necessary computing and communication infrastructure to issue alarms/alerts, whenever a pre-set threshold for the occurrence of a tsunami is crossed. The centre provides information about possibility of tsunami generation, its travel time and likely coastal areas to be affected, using model scenarios generated by Tunami-N2 numerical model.
Fig.6. Tsunami Hazard Map for the Cuddalore coast Constructing the tsunami hazard maps is the key step in tsunami risk assessment and forms the basis for evacuation and future landuse planning along coastal areas. To this end, a set of inundation scenarios were built based on realistic tectonic sources that can generate tsunamis in the Indian Ocean. Numerical models were constructed to predict the extent of inundation and run-up in each case, using a finite difference code TUNAMI N2 on nested grids derived from the high resolution elevation and bathymetry datasets. Elevation datasets derived from Cartosat-1 was used in the model to capture the extent of run-up and inundation in the land. Large scale tsunami hazard maps were constructed by 26
overlaying the numerical model outputs along with details on landuse, elevation, cadastral land parcels, infrastructure, high tide line, and coastal regulation buffer zones. These maps are useful for evacuation and landuse planning along the Indian coast (Fig.6).
3.2 Oil spill studies
The Indian Coast is susceptible to oil spills as was evidenced in the recent past when the Indian coast guard vessels and helicopters worked round the clock to contain the oil spilling from a stricken container vessel off Mumbai coast in the Arabian Sea. Marine oil spills have the potential to cause serious impacts to natural resources and the livelihoods of people that depend on them. The extent of impact however is influenced by a number of factors such as the type and amount of oil spilled, the physical characteristics of the affected area, the weather conditions at the time of the spill and the type and effectiveness of the response methods employed. For efficient oil spills management, the spilled oil should be brought under control at the earliest to limit damages to the bio-physical environments. Numerous oil spill models are available which predict the oil spill weathering profiles but does not predict the potential migration of the slick. Computer models using oceanographic and weather data provide a valuable support to both contingency planners and pollution response teams. Modelling exercise gives a clear idea about oil movement and will enhance the decisions concerning strategy development and the identification of necessary response capability. The operation of all computer models requires trained personnel. It is very essential the operator of these models understand their various limitations, such as the quality of information on water currents programmed into a model and the inherent difficulties in predicting some oil fate processes. Modelling is only a predictive tool and cannot readily replace the need to monitor a spill physically in the event of an actual incident. This can be effectively verified from aircraft or remote sensing or interpretation of visual observations of oil on water. GNOME (General NOAA Oil Modelling Environment), is a public domain trajectory model developed by NOAA, USA. The model is designed to fulfill the requirement of an oil spill responses team to combat an oil spill. The users have full access to all model parameters and scaling options, which can be used to set a site-
27
specific model. For example the coefficients for size and distribution of the uncertainty can be set to estimate the “Minimum Regret” trajectory. It can be used for •
Estimate the trajectory of spills by providing information about wind and weather conditions, circulation patterns etc. and the oil spill(s) that need to be simulated.
•
Predict the trajectories that can result from the inexactness (uncertainty) in current and wind observations and forecasts.
•
Use weathering algorithms to make simple predictions about the changes the oil will undergo while it is exposed to the environment.
•
Provide trajectory output (including uncertainty estimates) in a geo-referenced format that can be used as an input GIS based modelling system.
A GIS based modelling system is quite useful in oil tracking and provides very accurate and quick information about the type and extent of resources affected, which makes it a suitable management tool for dealing with oil spill for oil spill responders (Fig.7).
Fig.7 GIS based oil spill response system for Malvan coast, Maharastra, India 3.3 Coastal Flooding The primary emergency strategy for reducing the risk to life in a flood is the evacuation of the community at risk. Evacuation planning and implementation requires a clear understanding of the spatial distribution of the population at risk, the evacuation routes available and their susceptibility to being cut by water during the early rising stages of a flood. It is essential to know where and when an evacuation route will be cut by the rising 28
floodwaters. Knowledge of how parts of a community could become isolated, and therefore placed at great risk, once the last evacuation routes are cut, can be crucial to saving lives. Understanding the time varying flood surface comes by integrating topography, cadastral land parcel boundaries, air photos and predicted time varying flood extents and levels within a GIS environment. This involves disparate spatial and time varying data sets such as detailed topography, Cadastral land parcel boundaries, high resolution aerial photographs / imageries to illustrate evacuation routes and predicted time-varying water surface generated by a mathematical model. These systems are invaluable in flood emergency management plans and assist emergency management personnel during actual flood emergencies.
3.4 Coastal Erosion studies Coastal erosion is a chronic problem along most open-ocean shores of the Indian coast. As coastal populations continue to grow, and community infrastructures are threatened by erosion, there is increased demand for accurate information regarding past and present shoreline and the erosion and accretion patterns along the coast. In India, satellite data is widely used to study many aspects of coastal zone including coastal erosion and shoreline changes. Availability of remote sensing data for the last three decades has ensured synoptic and repetitive coverage for the entire coast and this information has been extremely useful in generation of spatial information on coastal environment at various scales and with
29
Fig.8 Location of Ennore Port and its impact on adjacent coastline Reasonable classification and control accuracy. In India, shoreline-change maps have been produced on 1:250,000, 1:50,000 and 1:25,000 scale using IRS LISS I, II and III, LANDSAT MSS/TM and SPOT data. The availability of 1-5 m high-resolution and stereo data from IKONOS, RESOURCESAT-I and CARTOSAT greatly facilitate preparation of large scale local level maps. The easy access to high spatial resolution data along with multi-spectral characteristics, repetitive coverage and development of geographic information system has provided new impetus to shoreline mapping and coastal erosion studies. ICMAM-PD had conducted field investigations and numerical modelling studies to study the impact of ports on the Indian shoreline (Fig.8).
3.5 Environmental Monitoring
Coastal environmental monitoring includes a wide variety of activities directed toward understanding the status and trends of environmental quality. Examples of field measured properties include water temperature, salinity, sediment loading, rainfall, water quality, etc.
Monitoring is conducted in many different ways depending, in part, on the
parameter(s) being measured, the monitoring objective, and the resources available to conduct the work. NCTPS NCTPS Ennore ETPS flyash
ETPS
Fishing Fishing Chennai port DOP Before commissiong of Ash-dyke -
30
Chennai port
After commissiong of Ash-dyke -
Fig 9: Discharges of fly-ash by Ennore Thermal Power Station
Remote sensing can, under certain conditions, contribute to environmental monitoring by allowing managers to obtain repetitive, nonintrusive, synoptic data for some parameters across broad spatial and temporal domains. With respect to water quality, certain sensors such as our own IRS-P4 OCM sensor can provide managers with data on productivity and suspended sediment concentration in water. The plume generated due to flyash discharge from the Ennore Thermal Power Plant before the commissioning of the flyask dyke is shown in Fig.9. GIS offers lot of scope in environmental pollution monitoring and management as field collected over space and time can be interpolated and plotted for effective management and monitoring (Fig. 10 )
DO (mg/l) 6.40 – 6.83 6.83 – 7.27 7.27 – 7.70 Fig. 10: Spatial distribution of DO at surface in Waters off Karwar
3.6 Geoinformatics for micro level planning
For detailed and micro level planning scientific knowledge on the relative vulnerability of the houses in a hazard prone area is essential for a successful hazard mitigation planning operation. A spatial database built on the relative vulnerability index of buildings in the coastal area that are prone to coastal hazards such as the tsunami and storm surges are calculated using Vulnerability Assessment Models. In order to carry out a Vulnerability assessment it is imperative to list all vulnerable parameters in the study area with respect to its population, built environment, socio-economics, ecosystems and environment. For 31
each of these parameters a list of impact elements are then identified. Extensive field visit are required to collect data on the impact element from the local population. For each household, data is collected on their location (lat, long) using GPS, house type, building material along with the relevant socio economic data. The relative vulnerability index is calculated for each house using a combination of structural vulnerability of buildings, and the water level during the hazard, socio and economic attributes of each of the houses (Fig.11).
Fig.11. Relative vulnerability Index for a coastal village in Cuddalore
4.0 Limitations
Satellites see only the surface and with a few exceptions, most remote sensing instruments can only image the surface of the earth. For example, AVHRR collects data about sea surface temperature, but these data only reveal the ocean’s “skin” temperature—the first few millimeters below the surface. Subsurface conditions must be collected with other kinds of instruments mounted on buoys and submersibles.
For all passive sensors, clouds, fog, haze, pollution, dust and other particulates affect the interpretation of imagery. Clouds and fog can completely obscure a satellite scene, 32
forcing the analyst to wait for the next pass of the satellite. Haze and particulates change the spectral response of ground features, so imagery must be calibrated to ensure it is accurate. Radar and other long-wave sensors avoid atmospheric limitations, but these instruments are not suitable for many applications.
A GIS offers a lot of scope to overlay data obtained from different sources such as remote sensing data, SOI toposheets, GPS data, field survey data etc. But the problem arise while trying to overlay the data obtained from different sources due to mismatch in coordinate system, projection, Scale, datum etc. Today spatial and aspatial data on different aspects of the coastal regions are available in different sources at different formats. Collection of all available data and bringing them together in a common framework is a huge exercise by itself but this exercise should be undertaken to make use of the vast repository of information available on the coastal areas. Care should be taken to see that data collected in future pertain to some uniform standard to effective usage of data in future.
5.0 Conclusion From risk identification to emergency response and recovery, information plays a vital role and the effective use of information is instrumental to reduce the impact of disasters. With the advancement of information and communication technology in the last few decades, lack of information is no longer a major issue for disaster risk reduction. The major issue, rather, is managing the information, translating it into a comprehensive knowledge for decision making and disseminating it to the communities at risk for action.
6.0 Acknowledgement
The inputs obtained from the work carried out by ICMAM-PD, Ministry of Earth Sciences, Govt. of India is duly acknowledged.
33
Integrated study on ecosystem status of SW coast of India Dr. V. Ranga Rao Scientist-E, ICMAM-PD, Ministry of Earth Sciences Government of India NIOT Campus, Pallikaranai, Chennai 600 100 E-mail:
[email protected] 1. Introduction
Marine ecosystems contain approximately 97% of the planet's water. They generate 32% of the world's net primary production. They are distinguished from freshwater ecosystems by the presence of dissolved compounds, especially salts, in the water. Marine ecosystems can be divided into many zones depending upon water depth and shoreline features. •
The oceanic zone is the vast open part of the ocean where animals such as whales, sharks, and tuna live.
•
The benthic zone consists of substrates below water where many invertebrates live.
•
The intertidal zone (littoral zone) is the area between high and low tides.
•
Other near-shore (neritic) zones can include estuaries, salt marshes, coral reefs, lagoons and mangrove swamps.
Ecosystems management is an approach to natural resource management that focuses on sustaining ecosystems to meet both ecological and human needs in the future. Ecosystem management is adaptive to changing needs and new information. UNEP promotes •
increasingly integrate an ecosystem management approach into development and planning processes;
•
acquire the capacity to use ecosystem management tools; and
•
realign their environmental programmes and financing to tackle the degradation of selected priority ecosystem services.
2.
SW coast of India
SW coast of India, the coastline of about 1200km long occupies with a very wide range of coastal ecosystems such as estuaries, lagoons, mangroves, backwaters, salt marshes, 34
rocky coasts, sandy stretches, and coral reefs which are characterized by unique biotic and abiotic processes. It exhibits rich biodiversity under goes large influences from anthropogenic and natural sources.
Large pwercentage of the population lives along the coast and is major hub for industrial development. Coastal cities, such as Goa, Karwar, Mangalore, Beypore, Cochin, Alleppy, Trivandrum and kanyakuamri located along tehis coast pays way to discrge large amount of sewage through industrial and domestic sources. This inturn affects the ecosystem chareter and ultimately the fish and biological rodcution along the coast. Everybody know the coast is charecterstic of influences fro upwelling and downlelling, mud banks, tar balls etc that directly or indirectly influences the coastl production and primary, secondary and tertiary profuction. Beach tourism has been growing, and there has been a large increase in terms of tourist infrastructures along various parts of the coast. These activities disturb traditional fishing activities and fishers; interfere with marine life and cause degradation of nearshore habitats. One of the major impacts has been caused on the quantity and quality of ground water resources, mainly due to heavy quantities of water pumped by hotels and other tourism infrastructures located in coastal areas.
Number of coastal areas and ecosystems are under stress due to growing aquaculture and agriculture activities. The success of green revolution leads to increased use of fossil energy, fertilizers, pesticides and irrigation needs. Intensive agriculture that uses high yielding varieties of seeds has an adverse effect on the environment because of its greater dependence on the use of chemical inputs and water. Rise in water table, ground water depletion and soil salinity are reported in different areas. Intensive aquaculture as an activity located in coastal areas, also has an impact on coastal ecosystems. Dumping industrial wastes is common in many parts of these areas, Some of the industrial effluents are toxic and can remain in the sea for a long time and accumulate in the organisms. Several pollutants have detrimental effects on most life forms and affect their breeding, growth, reproduction and survival.
For SW coast of India, studies on coastal ecosystems have been widely studied by many workers; however on studies on ecosystem modeling are meager. Few studies have 35
been carried out by ICMAM as a part of COMAPS programme. In 12th plan ICMAM is conducting a detailed integrated study on “Ecosystem modeling for SW coastal water of India”. The experienced gained by ICMAM in physical biogeochemical coupled modeling is shared in this training.
3. Importance of coupled ecosystem models Coastal Ecosystem models are very useful for simulating and analyzing the long-term dynamics and stability properties of complex ecosystems. They allow integrating information from different disciplines as well as analysing, interpreting and understanding field observations. Moreover, they allow alternative scenarios to be developed, simulated, analyzed, compared, and ranked according to their effect. They provide a basis for the development of tools for management support and policy advice.
Modeling is an integrated effort among scientists from the fields of physical, chemical, biological, geological oceanography and remote sensing together with modelers to cater to the needs of planners involved in ecosystem studies. •
Ecosystems are complex and often require complex models if their detailed behaviour is to be replicated.
•
One approach that allows greater understanding of basic process is the development of simplified models. We can deal with the sediment and water column response separately in simple models by exploiting the different time scales of sediment and water column response. In simple water column models, a variety of common formulations of phytoplankton–zooplankton interactions, and their implications for the steady-state response of phytoplankton and nutrients to increased nutrient load have to be studied.
•
However now days coupled models such as 1D, 2D and 3D models among physical and biogeochemical processes are being emerged. A 3D (three dimensional) numerical hydrodynamic model usually is developed as the basis for ecological modeling and long time simulations. The horizontal grid is rectangular with irregular meshes and cross sections of tributaries. The vertical grid uses real depth coordinates and the vertical axis is split into several layers bounded by fixed horizontal levels irregularly distributed.
36
Applications have focused on quantifying ecological effects of toxic chemicals and pesticides. We have to determine to study various approaches of time schedule: for example seasonal cycle: winter mixing, spring phytoplankton bloom, summer stratification and autumn upwelling. The environmental factors to be studied must include both, biotic variables such as chlorophyll-a concentration, primary production, phytoplankton extracellular release, and abiotic variables such as the concentration of dissolved inorganic and organic nutrients. Assessing a marine coastal ecosystem health is also an important study. The assessment includes the following five steps: •
review of human activities;
•
identification of human-induced stresses;
•
analysis of ecosystem responses to the stresses;
•
development of ecosystem health indicators; and
•
Assessment of ecosystem health.
The human interventions are often causing a transformation in the coastal ecology. Excessive nutrient loadings have become serious environmental issues in estuaries, bays and coasts causing eutrophication and unusual phytoplankton blooms. The nutrient distributions in coastal waters are controlled by a complex physical-chemical-biological interaction process associated with input, advection/dispersion and export. Since these are complicated and non-linearly coupled, studies on nutrient controlled phytoplankton production usually rely on water quality models involving transformation and utilization of inorganic and organic matters. Since phytoplankton forms the base in food chain and the successive dependent secondary and tertiary productions rely on phytoplankton, it is of paramount importance to initially model the phytoplankton production under changing environmental conditions, especially the nutrients, illumination, etc. Such a prediction system with reference to phytoplankton will pave way to predict the production at higher levels using the models, of course with lots of complexity.
The objectives of coastal ecosystem modeling is to understand the various factors and processes that cause the changes in coastal ecosystem productivity, under changing environmental conditions.
The scenarios developed using models would indicate the
quantum of primary, secondary and tertiary production under changing nutrient requirements 37
and other environmental conditions.
Such modeling activities are being carried out by
ICMAM-PD, Chennai for the past few years with the help of local institution of coastal states.
4. Ecosystem modeling for SW coast of India As the ICMAM-PD is already having sufficient experience in implementation of ecosystem models for semi-enclosed coastal bodies like 'chilika', ‘Coringa’, ‘Sunderbans’ and 'cochin backwaters' and with that experience it is planned to extend the study to an offshore region to develop an ecosystem model. The study area chosen for the study is a long coastline of Kerala, Karnataka and Goa states located on SW coast of India. The south west coast of India is a monsoon dominated coast. In this region, upwelling is a wind-driven process and the strength of alongshore winds stress modulates the coastal divergence and hence the input of cold up-welled water over the shelf. This region is a major fishing ground and plays a key role on India’s exploitable fisheries potential. The progressive deterioration of many of the shelf waters caused by anthropogenic activities. The states of Kerala, Karnataka and Goa sustain a significant share of coastal population and as a consequence, the entire coastal water bodies are getting intensely polluted due to the increased human activity. Rapid urbanization, industrialization and several engineering modifications are the major causes for deterioration of ecology of the region. Phytoplankton blooms has been found to be most abundant during this upwelling period that lasts from May-June to October-November as the denser nutrient rich water is brought to the surface, thereby increasing chlorophyll a and gross primary productivity. The excessive nutrient loads during monsoon and associated upwelling also result increase in respiration dominate photosynthesis leads hypoxia leading to decreased productivity. These biogeochemical cycles and hypoxia during monsoon plays a vital role in ecosystem functioning and determines its productivity. Such characteristics made the southwest coast unique and modelling the ecosystem productivity though challenging, throw a light in the impact of environmental conditions on ecosystem productivity.
ICMAM’s ESM Group – Motto
The usefulness of ecological simulation modeling results as much from the process (problem specification, model development and model evaluation) as from the product (the final model and simulations of system dynamics). Skill in the process of simulation modeling is gained 38
primarily through 1-practise, 2-practise and 3-practise. However, a keen awareness of what we are doing (in practice), why we are doing it (in theory), and why it makes (,) sense, is invaluable. Without this awareness we risk silly, kindergarten level mistakes; even experienced modelers are not immune from these pitfalls, which often come hidden and a thick covering of sophisticated quantitative techniques and associated jargon. (Of theory , practice and common sense---ecological modeling ; a common sense approach to theory and practice by William E Grand, Todd M Swannack, John Wiley and sons).
Ecological field experiments are time consuming and costly. Biologists are tempted to limit the physical oceanographic part to minimum and make "a best guess" based on e.g a few CTD stations. Such data, however, tells usually next to nothing about the physical processes which are necessary to interpret the biological data in a satisfactory way.....Herald (Physical oceanography and marine ecosystems: some illustrative examples. Scientia marina, 61, 93108, 1997).
Objectives
The main objective is to understand the biogeochemical processes and to develop an ecosystem model for coastal waters of SW coast of India and mainly to quantify and predict the primary production. The study is being carried out in an integrated manner by taking into consideration of various physico-bio-geo-chemical processes to understand the water quality and eutrophication conditions and ultimately to predict the primary production along the SW coast of India. On successful completion, we will go for the prediction of secondary and tertiary level production. In order to meet the above objective, the proposed study requires to cover the study area seasonally to collect data on hydrodynamic and biogeochemical processes.
Importance of Prediction of Primary production
Like fig 1b, we have to study whether the coast is characteristic of human interventions such as engineering modifications, hydraulic controls, industrial establishments etc. the ecosystem is under stress or not.
Excessive nutrient loadings from land drainage may cause
eutrophication, hypoxia, anoxia, and unusual phytoplankton blooms during monsoon 39
upwelling. As the primary production parameter the 'phytoplankton' forms the base for food chain (Figs 1c & 1d) and is the major controlling factor for secondary and tertiary production, ICMAM modeling activity is concentrated mainly on simulating the primary production. Primary production of the coastal ocean plays a key role in the carbon cycle also.
Fig1. Concepts of a) Ecosystem, b) Anthropogenic influences on coastal ecosystem, c &d) Food chain and interlink between primary, secondary, tertiary and predators production levels
Data collection and methodology
The data required for the study is being obtained from field measurements, historical data sets, Global data sets and also satellite data. The field measurements are also planned in association with CMLRE and COMAPS Institution (NIO, Kochi) on the basis of mutual data 40
sharing and model data exchange. Based on the collected data, the physical parameters such as sea level oscillations, tide & wave induced circulation, stratification and mixing, 3D coastal flow field, upwelling/ sinking index, climate and weather etc, are being analyzed. The ROMS/ HYCOM model output data on 2D & 3D flow field and sea levels has been obtained from INCOIS for the purpose of setting up of model boundary condition at 50m depth contour.
The bio-geo-chemical parameters such as temperature, salinity, dissolved oxygen (DO), chlorophyll a (Chl a), carbonaceous biochemical oxygen demand (C BOD ), ammonium nitrogen (NH 4 ), nitrate and nitrite nitrogen (NO 3 +NO 2 ), inorganic phosphorus (PO 4 ), organic nitrogen (DON), organic phosphorus (DOP) etc are being analyzed. The historical data (1988 to till date) on these parameters available with COMAPS and ICMAM database have also been collected and related analysis is going on. The main intention in analyzing these data is to understand the seasonal as well as annual climatic variations and also to study the four complex interacting ecosystem processes: the oxygen, the nitrogen, the phosphorus, and the phytoplankton cycles. By incorporating the above parameters and the nutrient cyclic processes the water quality simulation models are being set up by coupling the physical transport process. The ecosystem model for the secondary production is also being setup from the water quality model by including the kinetic equation representing zooplankton. The ecosystem model for tertiary production based on Ecopath/ Ecosim software has also been initiated and an interaction in this direction with CMFRI is also going on.
In all the above modeling activities, the anthropogenic influences such as agricultural and industrial activities are being considered by collecting water quality parameters from land derived inputs and river discharge data. Physical processes such as tides, land/ sea breeze influences, seasonal reversal of monsoons, annual variation in climate and episodic events such as cyclone/ depressions, El-Nino/ La-Nina phenomena, global climatic change, hydrological cycles, and associated sea level fluctuations on ecosystem dynamics are being considered. Analytical models as well as 2D and 3D coupled models on eutrophication, heavy metal and water quality with nutrients, chlorophyll a, temperatures, salinity and coliforms etc are being developed and applied to simulate the primary production and prediction. This type of ecosystem modeling aspects is being carried out on diurnal, seasonal as well as on annual cycles. 41
Total Chlorophyll pigments will be measured fluorometrically following JGOFS protocol. Particularly chlorophyll-a, fluoresce in the red wavelengths after extraction in acetone when they are excited by blue wavelength of light. The fluorometer excites the extracted sample with a broadband blue light and the resulting fluorescence in the red is detected by a photomultiplier. The significant fluorescence by phaeopigments is corrected by acidifying the sample which converts all of the chlorophyll-a to phaeopigments. By applying a measured conversion for the relative strength of chlorophyll and phaeopigment fluorescence, the two values can be used to calculate both the chlorophyll-a and phaeopigment concentrations. The data will be collected in two time domain (Pre-monsoon and Post monsoon) with synchoronous to satellite data available in cloud free seasons. However, data will also be required, immediately after the extreme weather conditions like cyclones and storms etc.
Study of species diversity with relation to space and time domain (Grid wise data collection): The common pigments that contribute towards total chlorophyll are: chlorophyll-a, chlorophyll-b, chlorophyll-c, carotenoids, phycoerythrin and phycocyanin etc., These suite of pigments constitute the various taxonomic groups of phytoplankton in sea-water. Predominantly, in Arabian Sea, diatoms dominate (~50-80%) followed by dinoflagellates (~15-40%) and some percentage of blue-green algae (5%). These conditions are different in event specific phenomenon like: blooming, cyclone induced productivity, and vertical mixing. Besides these Trichodesmium species are also abundant in the coastal waters of Arabian Sea. Periodically, the dominance of these species will be accounted and monitored and the absorption spectra will be measured using optical radiometers. Identifying P-I parameters (Pmax, α) with respect to species diversity: The species will be cultured in different saline and temperature environment to monitor the growth of the plankton. Based on the light availability, P-I curve has to be constructed to know the optimal growth of plankton.
Estimation of primary production using stable and radiogenic isotopic methods: A standard procure has to be followed to estimate the in-situ primary productivity as per the species dominance (site specific). In addition to this, the fast repetition rate (FRR) technique mostly based on the variable fluorescence characteristics of the phytoplankton will also be used to 42
estimate the primary productivity. The following outcome from this FRR technique study is proposed. - The nutrient status of the algae and their physiological response to nutrient limitation; Algal photoinhibition due to excessive visible/UV radiation; Algal physiological responses to the interaction of changing of nutrients and light fields.
Modeling approach
The approach is shown in flow chart (Fig 2). First, for the study area, we will collect physical parameters such as tides, waves, currents, bathymetry etc and based on the data, we will simulate the 2d & 3d models to reproduce the water levels and flow field; incorporating
later by
the biogeochemical parameters by considering conservative and non-
conservative properties and advection and dispersion mechanisms, we will simulate the water quality parameters such as temp, salinity, nitrite, nitrate, oxygen, DO, BOD, plankton, chlorophyll etc. Later by utilizing various coefficients of nitrogen, phosphorous, oxygen and plankton cycles we will simulate the eutrophication conditions and the output will be validated with the insitu and satellite derived data. Once we validate the model, the model will be taken as operational forecasting mode. For this, the following models are bieng utilised.
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Fig. 2. Study approach for Ecosystem Modeling for SW coastal waters of India Analytical models
Analytical models are often complex mathematically, and work best when dealing with relatively simple (often linear) systems, specifically those that can be accurately described by a set of mathematical equations whose behavior is well known. For example, the observed data on air temperature available for the period 1990- 2007 has been used to study the annual variation for the past two decades. Further the data has been plotted in excel and a polyline trend line will be constructed. Based on the polyline trend equation the data gaps have been predicted and filled and also trend equations will be used to forecast the ecosystem parameters. These forecast parameters will be given as input for boundary conditions of simulation models.
Simulation models
Simulation models on the other hand, utilize numerical techniques to solve problems for which analytical solutions are impractical or impossible. Simulation models tend to be more widely used, and are generally considered more ecologically realistic. Hydrodynamic module: The hydrodynamic module simulates water level variations and flows (Fig 3) in response to a variety of forcing functions in lakes, estuaries and coastal regions. The effects and facilities include - bottom shear stress, wind shear stress, barometric pressure gradients, Coriolis force, momentum dispersion, sources and sinks, evaporation, flooding and drying, wave radiation stresses.
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Fig 3. Typical flow field simulations from 3D hydrodynamic model
The AD module: simulates the spreading and fate of dissolved or suspended substances when provided with the flow field from the hydrodynamic module. The AD model specifications includes - conservative substances, linear decay, dispersion coefficients, sources/sinks
The WQ module; Describes the resulting concentrations of bacteria, which threatens bathing water quality, oxygen depletion due to release of BOD, excess concentrations of nutrients and degradation of chemical substances. The above mentioned processes are described by a system of differential equations describing the physical, chemical and biological processes. The WQ module is coupled to the AD module in order to simulate the simultaneous processes of transport and dispersion. The following aspects can be investigated using the WQ module •
Spreading/fate of faecal and/or total coliform bacteria and die-off rates (first order decay) in relation to physical-chemical factors
•
Biological oxygen demand from domestic as well as waste water sources
•
Production of nutrients (nitrogen and phosphorous) by degradation of organic matter
•
Denitrification/nitrification processes 45
•
Chlorophyll production linearly dependent on the oxygen production and MichaelisMenten dependent on inorganic nitrogen and phosphorus.
•
Oxygen conditions affected by discharged organic matter, sediment oxygen demand, reaeration as well as oxygen production by phytoplankton and respiration in the water column.
The EU module:
Describes the relationship between available nutrients (nitrogen and
phosphorous) and the succeeding growth of phytoplankton in the water column as well as the growth of benthic vegetation. The interactions are described by a system of differential equations describing the physical, chemical and biological processes. The EU module is coupled to the AD module in order to simulate the simultaneous processes of transport and dispersion processes. The following state variables, processes and derived parameters are covered •
Growth and biomass of phytoplankton (dependent on light, temperature, sedimentation and grazing by zooplankton as well as the internal and external pools of nutrients)
•
Chlorophyll-a concentration based on phytoplankton carbon
•
Zooplankton dynamics (grazing rate is described by a type III functional response)
•
Biomass and distribution of stationary benthic vegetation (dependent on light, temperature and nutrients)
•
Oxygen conditions depending on biological activity and reaeration
•
Nutrient uptake by phytoplankton (both during limited and non-limited conditions) and benthic vegetation (Michaelis-Menten kinetics)
•
Release of inorganic nutrients due to decomposition (first order decay) of organic matter in the water phase and in the sediment.
•
Secchi disc depth
WASP Model
WASP model helps users interpret and predict water quality responses to natural phenomena and manmade pollution for various pollution management decisions. WASP is a dynamic compartment-modeling program for aquatic systems, including both the water column and 46
the underlying benthos. WASP allows the user to investigate 1, 2, and 3 dimensional systems, and a variety of pollutant types. The time varying processes of advection, dispersion, point and diffuse mass loading and boundary exchange are represented in the model. WASP also can be linked with hydrodynamic and sediment transport models that can provide flows, depths, velocities, temperature, salinity and sediment fluxes. WASP also has been used to examine eutrophication of SW coastal waters
Ecopath/ Ecosim
Ecopath is a powerful software system which uses simulation and computational methods to model marine ecosystems. It is widely used by marine and fisheries scientists as a tool for modeling and visualizing the complex relationships that exist in real world marine ecosystems.
Outcome
The Ecosystem Modeling Program develops a sustainable management solution to support ecosystem-based management of the coastal ocean resources, including fisheries. Mathematical computer-based models that synthesize information about many features of an ecosystem provide Increased understanding of interactions among the components of the coastal ecosystems Improved synthesis based on standardized ecosystem data Improved ability to evaluate and adapt ecological monitoring efforts in the region The ability to simulate the outcomes of a range of possible management actions to clarify tradeoffs among the interests of stakeholders
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Marine Pollution – An Overview Prof. Dr. N R Menon Dean Faculty of Climate Variability, KUFOS & Emeritus Professor, CUSAT, Kochi & Co-Chairman, Nansen Environmental Research Centre (India), Kochi
Marine pollution has been defined by the group of experts on the Scientific aspect of Marine pollution (GESAMP) as the introduction directly or indirectly of substances or energy into the marine environment including estuaries resulting in much deleterious effects as harm to living resources, hazards to human health, hindrance to marine activities including fishing, impairment of quality of sea water and reduction of tourism amenities. The materials considered as marine pollutants are categorized under different broad categories. Organic compounds such as compounds of carbon produced either by living organisms or synthetically, petroleum hydrocarbon, pesticides, polychlorinated biphenyls, heavy metals such as mercury, lead, cadmium, arsenic, chromium, vanadium etc., belong to these categories, Radio active waste materials produced from uranium mining, enrichment and fabrication of fuel assemblies, reprocessing of spent fuel, decommissioning of nuclear power plants, accidents and wastes occurring from nuclear reactions an also lead to marine pollution. Thermal or heat pollution occurs when heated effluents are released with the sea causing sudden change in water temperature. Release of infectious agents viz pathogens that can produce sickness or biological imbalance in marine plants or animals or in humans consuming such pathogen containing sea food are the immediate danger to human health. Eutrophication of coastal water can be caused by nutrients loaded domestic sewage, agricultural runoff etc. Sewage sludge, Organic waste materials from the meat and fish processing plants contain materials with high BOD which can deplete the dissolved oxygen level of the receiving water considerably. A very recently detected source of marine pollution is electromagnetic pollution – which are the magnetic and electric fields generated by underwater electronic instruments. Earlier, these small fields, which drop off quickly with distance from the source, was not considered to pose any health hazard. Recent studies have
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shown that sharks, dolphins, whales etc are affected by the electro-magnetic waves when they come in contact with the electro-magnetic fields. There are various methods and yardsticks employed to express the effect of pollution on the marine organisms. In this respect, it would be necessary to distinguish between natural pollutants and anthropogenic pollutants. Natural pollutants are substances suddenly released into the water in large quantities such as volcanic eruption, CO 2 , Oxides of nitrogen, sulphur, oil well disaster etc. The recent oil well disaster in the Gulf of Mexico is a glorious example for natural pollution which drastically affected the fisheries of the Gulf of Mexico. Whether natural or anthropogenic, this type of pollution causes damage by interfering directly or indirectly the biochemical process of marine organisms and eventually may even upset the integrity of the marine ecosystem. These types of contaminants can lead to lethal or sub lethal effects. Lethality is the end of the way, while sub lethal effects could be changes in the body own function, structure, activity etc. The lethality or sub lethality of a pollutant is controlled by the quantity and the range of toxicity of the pollutants. This can demonstrated by a dose – response curve.
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Pollution may come from a point source or a non point source. Usually the point source refers to a factory waste water(effluent) outlet. In the case of point source pollution (the most common instance of coastal pollution) the concentration of the substance or the intensity of the effects decreases with increasing distance from the pint source. This aspect is the governing factor to define the effluent quality standards and the level while granting permission for effluent disposal. The ecological half life has also been introduced in the case of non –degradable components of an effluent especially pesticides and heavy metals. Notwithstanding the nature and quantity of pollutants dumped into the coastal waters there are natural processes which will alter the nature and quality f the pollutants. We can call this as natural purification.
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Activities that pollute the oceans and the sources of Marine Oil Pollution There are many factors which influence the toxicity of a pollutant. The effects of a toxin vary with concentration. Some toxin may be lethal even at very low concentrations. The levels that are beneficial, harmful or lethal may differ widely, quantitatively and qualitatively. Coastal pollution is often guided by the definition of thresholds. Normally a threshold is a level below which no effect occurs and above which effects begin to occur. Dumping wastes and ensuring dilution and dispersion can lead to a situation where the toxicant would below threshold levels leading to an ideal situation for effluent disposal. Unfortunately synergic and antagonistic nature of toxins make a judicial and agreeable concentration in the coastal waters rather difficult. Often this means that thresholds can change if an organism is exposed to a combination of toxins in concentration. Long term (Chronic) or short term (episodal) pollution require different ways and means of handling. Chronic pollution due to effluent discharge, river run off…etc. are often misunderstood while analysing the effects. Nutrient runoff from river inputs into the sea often cannot be controlled by any law. On the other hand episodal pollution of coastal water (an oil spill) require immediate attention and there are various approved and practical methods to handle the situation. The vulnerability of coastal ecosystems to pollutant insult depends on factors like physical and chemical properties of the sediment and the nature and quantity type of inputs. Radioactive materials and pesticides require special mention since the life of these materials in the aquatic system is controlled by very intricate factors governing the nature of the substances. Various factors can be attributed to judge the vulnerability of aquatic ecosystem to handle the effects of pollutant and this is cardinally controlled by the vulnerability of the 51
ecosystem. Different factors like bio- availability, bio-accumulation, trophic relationship, internal effects and transfer through reproductive products are the most important ones which decide the fate of marine organisms living in polluted waters. To summarise, it is highly necessary that enough information is made available to the agencies who are involved in processing and handling of various materials in the industrial units from where the effluents reach the sea. It is highly important that we realise that marine pollution is the product of anthropocentric attitude of the humans. Human activities have dramatically increased the intensity, pace and kinds of environmental changes, proving several adaptive challenges to marine organisms. By treating the marine environment as if it matters, we not only demonstrate commendable humility but also benefit our own selfinterest.
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FUNDAMENTALS OF REMOTE SENSING Dr. S K Dash Scientist-D Ministry of Earth Sciences ICMAM-Project Directorate, Chennai 600100
[email protected] 1.0 Introduction
REMOTE SENSING is the science and art of obtaining information about an object, area, or phenomenon through the analysis of data acquired by a device that is not in contact with the object, area or phenomenon under investigation.
1.1 Components of remote sensing system
Fig. 1 - components of Remote Sensing Energy Source or Illumination - the first requirement for remote sensing is to have an energy source which illuminates or provides electromagnetic energy to the target of interest.
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Radiation and the Atmosphere - as the energy travels from its source to the target, it will come in contact with and interact with the atmosphere it passes through. This interaction may take place a second time as the energy travels from the target to the sensor. Interaction with the Target - once the energy makes its way to the target through the atmosphere, it interacts with the target depending on the properties of both the target and the radiation. Recording of Energy by the Sensor - after the energy has been scattered by, or emitted from the target, we require a sensor (remote - not in contact with the target) to collect and record the electromagnetic radiation. Transmission, Reception, and Processing - the energy recorded by the sensor has to be transmitted, often in electronic form, to a receiving and processing station where the data are processed into an image (hardcopy and/or digital). Interpretation and Analysis - the processed image is interpreted, visually and/or digitally or electronically, to extract information about the target which was illuminated. Application - the final element of the remote sensing process is achieved when we apply the information we have been able to extract from the imagery about the target in order to better understand it, reveal some new information, or assist in solving a particular problem.
2.0 Electromagnetic Energy The sun provides most of the energy, which we sense as light. This energy consists of electromagnetic (EM) waves, which travel in harmonic, sinusoidal motion. Although all EM radiation (EMR) travels at the same speed (3 x 10^8 m sec-1), the wavelengths (that is, the distance between consecutive troughs or crests) of the waves may vary. The resulting range of wavelengths gives rise to the Electromagnetic Spectrum, illustrated in Figure 2. The highenergy forms of EMR, such as X-rays, have short wavelengths and high frequency (since the shorter the distance per cycle, the greater the number of cycles required to achieve the same speed), while low energy forms, such as radio waves, have long wavelengths and low frequency.
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The entire range of radiant energies or wave frequencies from the longest to the shortest wavelengths is the categorization of solar radiation.
Fig. 2 - Electromagnetic Spectrum
Satellite sensors collect this energy, but what the detectors capture is only a small portion of the entire electromagnetic spectrum. The spectrum usually is divided into seven sections: radio, microwave, infrared, visible, ultra-violet, x-ray, and gamma-ray radiation.
2.1 Sources and type of electromagnetic energy used in R S •
Natural electromagnetic energy
•
Man-made electromagnetic energy - microwave wavelengths
- visible light, NIR, MIR and TIR
3.0 Atmospheric Effect
Radiation from the Earth's surface undergoes significant interaction with the atmosphere before it reaches the satellite sensor. This interaction with the atmosphere can be severe, as in the case of cloud contamination, or minor, as in the case where there is essentially a clear sky field of view. The propagation of electromagnetic radiation through the atmosphere is affected by two essential processes: absorption and scattering. Absorption occurs when a fraction of energy passing through the atmosphere is absorbed by some of the constituents in 55
the atmosphere and re-emitted at different wavelengths. Scattering occurs when a fraction of energy passing through the atmosphere has it's direction altered through a diffusion of radiation by small particles in the atmosphere. The type and significance of the scattering depends upon the size of the scattering element compared to the wavelength of the radiation.
4.0 Platforms There are three main categories of platforms namely ground borne, air borne and space borne (Fig.3). A brief description of each of these follows:
Fig. 3 - Types of Platforms
Platforms in space are not affected by atmosphere and hence the orbits can be defined. Entire earth or any part of earth can be covered at specific intervals. The mode can be geostationary permitting continuous sensing of a portion of earth or sun-synchronous with polar orbit covering the entire earth at same equator crossing time. Brief satellite taxonomy is given here.
5.0 Satellite Sensors The sun provides a very convenient source of energy for remote sensing. The sun's energy is either reflected, as it is for visible wavelengths, or absorbed and then re-emitted, as it is for thermal infrared wavelengths. Remote sensing systems which measure energy that is naturally available are called passive sensors. Passive sensors can only be used to detect energy when the naturally occurring energy is available. For all reflected energy, this can only take place during the time when the sun is illuminating the Earth. There is no reflected energy available from the sun at night. Energy that is naturally emitted (such as thermal 56
infrared) can be detected day or night, as long as the amount of energy is large enough to be recorded.
Active sensors, on the other hand, provide their own energy source for illumination. The sensor emits radiation which is directed toward the target to be investigated. The radiation reflected from that target is detected and measured by the sensor. Advantages for active sensors include the ability to obtain measurements anytime, regardless of the time of day or season. Active sensors can be used for examining wavelengths that are not sufficiently provided by the sun, such as microwaves, or to better control the way a target is illuminated. However, active systems require the generation of a fairly large amount of energy to adequately illuminate targets. Some examples of active sensors are a laser fluorosensor and synthetic aperture radar (SAR).
ACTIVE REMOTE SENSING
PASSIVE REMOTE SENSING
6.0 Scanners Across-Track Multispectral Scanning (Whiskbroom)
Such systems scan the terrain along scan lines that are at right angles to the flight line. This allows the scanner to repeatedly measure the energy from one side of the aircraft to the other. Data are collected within an arc of 90º-120º. The incoming energy is separated (Dichroic grating) into several spectral Components that are independently sensed.
Along-Track Multispectral Scanning (Push broom Scanners) The difference is the manner in which each scan line is recorded. A linear array consisting of numerous CCDs (detectors) is used to scan. The size of detectors determines the size of each ground resolution cell. Each spectral band (or channel) requires its own array 57
Advantages of Push broom over Whiskbroom: •
Longer dwell time à stronger signal, greater range of sensed signal à better
spatial and radiometric resolution ••
Better geometry (fixed relationship among detector elements)
Disadvantages: •
Need to calibrate more detectors
••
Limited range of spectral sensitivity of commercially available CCDs
7.0 Resolution Consideration Resolution-resolving power to distinguish between signals that are spatially near or spectrally similar
SPECTRAL :
Sensitive to specific wavelength intervals
SPATIAL
Smallest unit that can be resolved
:
TEMPORAL :
Revisit of sensor to same area
RADIOMETRIC
:
Ability to detect slight radiance difference
It is generally believed that improvements in resolution increase the probability that phenomena may be remotely sensed more accurately.
The trade-off is that any improvement in resolution usually will require additional data processing capability for either human or computer assisted analysis
8.0 Radiation - Target Interactions Radiation that is not absorbed or scattered in the atmosphere can reach and interact with the Earth's surface. There are three (3) forms of interaction that can take place when energy strikes, or is incident (I) upon the surface. These are: absorption (A); transmission (T); and reflection (R). The total incident energy will interact with the surface in one or more of these three ways. The proportions of each will depend on the wavelength of the energy and the material and condition of the feature. Absorption (A) occurs when radiation (energy) is absorbed into the target while transmission (T) occurs when radiation passes through a target. Reflection (R) occurs when radiation "bounces" off the target and is redirected. In remote 58
sensing, we are most interested in measuring the radiation reflected from targets Features on the Earth's surface react differently in various `bands' of the spectrum. Spectral reflectance for specific features can be graphed. The individual response of certain features in specific bands is commonly known as the `spectral signature'.
8.1 Spectral response of vegetation, soil and water Figure 4 shows typical spectral reflectance curve for three basic types of earth features: healthy green vegetation, dry base soil and clear lake water.
Fig. 4 Spectral Reflectance Curves for vegetation, soil and water Spectral reflectance curves for healthy green vegetation almost always manifest the peak-and-valley configuration. The pigments in plant leave dictate the valleys in the visible portion of the spectrum.
Chlorophyll, for example, strongly absorbs energy in the
wavelength bands centered at about 0.45 and 0.67 μm. At about 0.7 μm, the reflectance of healthy vegetation increases dramatically. In the range from about 0.7 to 1.3 μm, a plant leaf typically reflects, 40 to 50 per cent of the energy incident upon it. Plant reflectance in the range 0.7 to 1.3 μm results primarily from the internal structure of plant leaves. Because this structure is highly variable between plant species, reflectance measurements in this range often permit us to discriminate between species, even if they look the same in visible wavelengths. The soil curve shows considerably less peak and valley variation in reflectance. That is, the factors that influence soil reflectance act over less specific spectral bands. Some of the factors affecting soil reflectance are moisture content, soil texture (proportion of sand, silt 59
and clay), surface roughness, presence of iron oxide and organic matter content. These factors are complex, variable and interrelated. For example, the presence of moisture in the soil will decrease its reflectance. Soil moisture content is strongly related to soil texture: coarse, sandy soils are usually well drained, resulting in low moisture content and relatively high reflectance; poorly drained fine textured soils will generally have lower reflectance. Two other factors that reduce soil reflectance are surface roughness and content of organic matter. The presence of iron oxide in a soil will also significantly decrease reflectance.
Considering the spectral reflectance of water, probably the most distinctive characteristic is the energy absorption at near infrared wavelengths. High transmission typifies these wavelengths with a maximum in the blue green portion of the spectrum. Waters containing large quantities of suspended sediments resulting from soil erosion normally have much higher visible reflectance than other "clear" waters in the same geographic area. Different surface features, thus, return different amounts of energy in different wavelengths of the electromagnetic spectrum. Detection and measurement of these spectral signatures enables identification of surface features both from air borne and satellite borne platforms. But often, similar spectral responses from surface features create spectral confusion leading to misinterpretation and misclassification. This can be overcome by systematic ground data verification. 9.0 Applications There are a number of remote sensing sensors available today and each sensor is designed for a specific purpose. With optical sensors, the design focuses on the spectral bands to be collected. With radar imaging, the incidence angle and microwave band used plays an important role in defining which applications the sensor is best suited for. Each application itself has specific demands, for spectral resolution, spatial resolution, and temporal resolution.
Fig.5 Applications of Remote Sensing 60
Spectral resolution refers to the width or range of each spectral band being recorded. As an example, panchromatic imagery (sensing a broad range of all visible wavelengths) will not be as sensitive to vegetation stress as a narrow band in the red wavelengths, where chlorophyll strongly absorbs electromagnetic energy. Spatial resolution refers to the discernible detail in the image. Detailed mapping of wetlands requires far finer spatial resolution than does the regional mapping of physiographic areas. Temporal resolution refers to the time interval between images. There are applications requiring data repeatedly and often, such as oil spill, forest fire, and sea ice motion monitoring. Some applications only require seasonal imaging (crop identification, forest insect infestation, and wetland monitoring), and some need imaging only once (geology structural mapping). Obviously, the most time-critical applications also demand fast turnaround for image processing and delivery - getting useful imagery quickly into the user's hands. In a case where repeated imaging is required, the revisit frequency of a sensor is important (how long before it can image the same spot on the Earth again) and the reliability of successful data acquisition. Optical sensors have limitations in cloudy environments, where the targets may be obscured from view. In some areas of the world, particularly the tropics, this is virtually a permanent condition. Polar areas also suffer from inadequate solar illumination, for months at a time. Radar provides reliable data, because the sensor provides its own illumination, and has long wavelengths to penetrate cloud, smoke, and fog, ensuring that the target won't be obscured by weather conditions, or poorly illuminated.
9.0 Refernces •
Canadian center for remote sensing (www.ccrs.nrcan.gc.ca)
•
Mather Paul, M. Computer Processing of Remotely-Sensed Images: An Introduction. 2nd ed
•
Sabins, F.F. (1997) Remote Sensing: Principles and Interpretation, 3rd ed. New York
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COMPUTATION OF SUSPENDED SEDIMENT TRANSPORT IN COASTAL AND ESTUARINE WATERS – A CASE STUDY Dr. K. Rasheed Scientist-D ICMAM Project Directorate, Chennai-600 100 Email:
[email protected] 1.0 Introduction Understanding the sediment transport processes is essential to coastal and estuarine developmental activities, engineering applications and mineral resource extraction. The transport of sediment influences the construction of economically viable harbours, the construction of coastal power stations and refineries, coastal flood defense and also the safety of offshore platforms and pipelines etc.
Coastal and estuarine sediment transport is a complex phenomenon due to dynamic processes like wind, waves, tides and currents. Sediments which are occurring this environment are either from the terrestrial or from marine origin, varying from clay to coarse sand. Currents, tides, wind and density driven currents carry these sediment away from the coast or towards the coast. This document outlines the sediment transport processes in coastal and estuarine waters and brings out the salient results of a case study carried out at the Cochin estuarine system for sediment transport and related aspects.
2.0 Coastal and estuarine sediment transport processes Coastal sediment transport takes place in near-shore environments due to the action of waves and currents. Coastal sediment transport results in the formation of characteristic coastal landforms such as beaches, barrier islands, capes etc. The shape of a coast is heavily dependent on the sediment transport processes. The environmental condition is the main factor of how much the erosion/deposition will take place in a particular area of the coast. The coastal sediment transport determines the nearshore bathymetry characteristics and coastal topography which significantly affects coastal processes which is having a great concern for the coastal engineers and policy makers. The longshore transport is mainly caused by the waves approaching to the shore with an angle to the shoreline. This longshore 62
current as well as rip currents is a major causative factor in determine the long-term shoreline changes. Sediment transport is broadly divided into two categories: Suspended sediment transport and bedload transport depending on the size of the bed material and flow conditions. When the value of bed shear velocity exceeds the fall velocity of the particles, the sediment particles can be lifted up at which the upward turbulent forces will be comparable with or of higher order than the submerged weight of the particles and as a result the particles may go in suspension (van Rijn, 1985). The sediments which are transported as suspended are of small in size, with stronger wave/current force, bigger particles can be transported and more sediment concentration will occur in the water column.
Bedload transport is a form of sediment transport and is when particles are dragged by the seabed. The wave force forms a back and forward motion at the seabed which moves bigger particles from one place to another. Transport of grains by rolling, hopping and sliding along the bed in response to friction, and, in the case of sloping bed, gravity is the controlling factor. This is known as bed load transport. If the flow is fast enough and the grain is fine, sediment will be put into suspension up to a height of several meters above the bed and is carried by the currents. This type of transport is known as suspended sediment transport. A sediment grain is moved in suspension when the shear velocity is equal to or more than the settling velocity (Singh, 1980). This type of transport is usually seen in coastal and estuarine waters. Deposition occurs with suitable conditions when the sediment grain comes into rest as bed load transport or settling out of suspension.
3.0 Fall Velocity, Grain Size and Shear Velocity The fall velocity is the terminal velocity reached by a sediment particle as it falls through the fluid medium where the fluid drag retarding the particle is equal to the downward gravitational pull. The fall velocity (Ws) of the sediment depends on the grain size of the sediment (D). The fall velocity increases with grain diameter. For silt and clays, the fall velocity varies as D2 and for gravel it varies as D1/2. An important parameter for sediment transport is the shear stress ( ĩ ), which is tangential force per unit area that a moving fluid exerts on the sediment bed, which causes the transport. In a wave dominated case, it is related to the horizontal velocity (u) just above the top of the boundary layer, 63
Shear stress, Ĩ = 1/2ρf w u2, where ‘ρ’ is the fluid density and f w is the friction factor, which is inversely related to the dimensionless term (a/k s ), where ‘a’ is the orbital excursion amplitude and k s is the bed roughness (King, 2005).
4.0 Computation of sediment transport in coastal environments The sediment transport rate is defined as the amount of sediment per unit time passing through a vertical plane of unit width perpendicular to the flow direction. The amount of sediment may be measured by mass or by volume and its unit of sediment transport is given by kg m-1s-1 or m3 m-1s-1. The sediment transport rate in the sea has magnitude and direction and it is considered as a vector quantity. Longshore transport consists of the transport of sediments (clay, silt and sand) along a coast at an angle to the shoreline, which is dependent on prevailing wind and wave direction. This process occurs in the littoral zone. The process is also known as littoral drift. Longshore transport is influenced by several aspects of the coastal system, with processes that occur within the surf zone largely influencing the accretion and erosion of sediments.
The most common method of calculating the longshore sediment transport rate is by using the CERC formula (USACE, 1984), I = K{ρg1.5/16r b 0.5}* H b 2.5 *sin (2α b ), where ‘I’ is the total immersed weight longshore transport rate, K is an empirical coefficient, r b is the breaker index (0.78), H b is the breaking wave height and α b is the wave angle at breaking. If the longshore transport rate is transformed into the volumetric sediment transport rate, the above equation becomes, Q = K (ρ√g/(16r b 0.5 *(ρ s -ρ) (1-P) (1.426)2.5) H b 2.5 sin (2α b ), where ρ s is the mass density of sediment particles in kg/m3 and P is the sediment porosity. CERC equation includes only the longshore transport rate due to oblique incident waves. Kamphuis et al. (1986) developed an empirical formula that includes the beach slope and sediment grain size, Longshore sediment transport rate, Q= 1.28*(H sb
m)/d * (sin(2.θ b ), where H Sb is
3.5
the significant wave height at breaking, ‘d’ is the sediment grain size and ‘m’ is the beach slope and θ b is the wave breaker angle. 64
Later Kamphuis (1991), suggested an empirical formula for the prediction of longshore transport rate, modifying his 1986 formula by adding the influence of peak wave period, T p . Q = 7.3 H2 sb T1.5 p m p 0.75D 50 -0.25 sin0.6 (2α b ), where Q is the longshore transport rate (kg/sec), H sb is the significant wave height at breaking, T p is the peak wave period in seconds, m p is the beach slope from the beaker line to the shoreline and D 50 is the median grain size (mm) and α b is the wave angle at breaking. According to Pritchard (1967), an estuary is a semi-enclosed coastal body of water, which has a free connection with the open sea and within which seawater is measurably diluted with freshwater derived from land drainage. The sediment transport in the estuarine environment is somewhat different from the coastal waters. In estuary, the transport is controlled by the tidally driven flow from the seaside and freshwater discharge from land side and this will oscillate to the downstream and upstream of the estuary. Transport of sediment in coastal and estuarine waters is mainly deals with sand, silt and clay fractions especially in a tropical estuary, some bigger fractions are also coming into these waters. The sand is defined as sediment having grain diameters in the range from 0.062 to 2mm. Finer sediments are taken into account as clay and silt (mud) which are having grain diameters < 0.062mm. Grains larger than 2mm are classed as gravels. The sediment in coastal and estuarine waters transported by the basic processes of entrainment, transportation and deposition. These three processes takes place at the same time and may interact with each other (Soulsby, 1997).
Entrainment takes place as a result of the friction exerted on the sea bed by the currents and/or waves, with turbulent diffusion possibly carrying grains up into the suspension. The processes of entrainment of grain (beginning of grain movement) on a sediment bottom is mainly determined by the water flow velocity and grain size of sediments. However, shape of sediment grains, position of the grain, composition of sediment and turbulence of the flow and type of packing of the sediments are also important in effecting the entrainment velocity of sediment grains.
5.0 Estuarine sediment transport – a case study The Cochin estuary, located at the middle of Kerala state, which forms more or less a northward extension of the Vembanad Lake, which has all the characteristics of a typical 65
tropical estuary (Udaya Varma et.al, 1981 and Lakshmanan et. al. 1982). It is well connected to the rivers and lagoons on one side and to the Arabian Sea on the other side. Major rivers which discharge freshwater directly into the system is Periyar from the northern part and Muvattupuzha from the southern part. The other rivers connected to the estuary are Pamba, Manimala, Minachil and Achankovil. The total volume of discharge for these six rivers is approximately 2x1010 m3/year. The highest discharge is during monsoon season and the least during pre-monsoon season (Srinivasan et.al; 2003a). Cochin harbour is the second largest harbor along the south-west coast of India. The Cochin estuarine harbor (9°56’-10°02’N, 76°13’-76°18’E) is situated along the south west of India (Fig.1). The navigational channels of Cochin harbor consists of an approach channel (which is about 10km long, depth of about 13.5m) and two inner channels, the Ernakulum channel (5km long, 11.6m deep) and Mattanchery channel (3km long, 9.75 deep) on either side of Willingdon Island. Depths are maintained by frequent dredging at around 10-13m. The sediment transport and its budgets are very important at this site for uninterrupted port operations especially in the navigational channels.
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A case study was conducted at Cochin harbour to identify the sediment dynamics during pre-monsoon, monsoon and post-monsoon seasons. Selected stations were located at boundary within the inner harbor connecting Ernakulum channel, Bolghatty, Vallarpatam, Vypeen-FortKochi (Cochin Gut) and Mattancherry channel, to account for all inflow/outflow 67
routes of sediments within the harbor region. Inorder to quantify the suspended sediment transport in this estuarine environments, current speed, current direction and turbidity values were obtained at selected stations along the estuary. 6.0 Materials and Methods The suspended sediment concentration expressed in Jackson turbidity unit (JTU) is determined in the field by making use of insitu turbidity meter which makes use of the optical scattering principle. Current speed and direction were determined by direct reading current meter with an accuracy of +/-2 cm/s. Average values of turbidity and current for the three stations were taken for the Ernakulum channel. Two stations for Bolghatty east and one station for Bolghatty west. Three stations for Cochin gut (between Vypeen Island and Fort Cochin) and three stations for Mattchancherry channel are taken for this study. The tide averaged area was calculated for each transect by the formula, A tide = A + 0.5 R*B + H L *B where A tide
-
the tide averaged area
A
- the area of the channel
R
- the tidal range
B
- the width of the channel
HL
-
the height at the lowest tide
7.0 Computation of sediment transport The turbidity is converted into load values in mg/l using the formula 0.0676092*x + 15.643 where ‘x’ is the turbidity in JTU. The current speed is averaged under each transect and is multiplied with the tide-averaged area, which gives the volume transport in m3. Knowing the averaged turbidity in mg/l in transect(s), the suspended sediment transport rate was determined. The value is taken as positive during the ebb phase and negative during the flood phase. The suspended sediment transport corresponding to flood and ebb phase is then computed for a full tidal cycle (1day); further the net suspended sediment transport for a month at each location is estimated, from these values as net transport under each season for respective segments in this estuary. 68
8.0 Results The study revealed that, the net transport of suspended sediment through estuarine system during pre-monsoon period was as follows: the transport rates are high through Mattancherry channel (268.8 x 106Kg), followed by Cochin Gut (156.0 x 106Kg) and Bolghatty East (-91.20x106Kg) when compared to Bolghatty West (57.6x106 Kg) and off Shipyard (45.60x106Kg) regions. The reason for this hike in suspended sediment is attributed to the intensive dredging activities during this period along with strong tidal inflow, which brings huge quantities of suspended sediment of marine origin. The net suspended sediment transport during monsoon season showed that a loss occurs along the Mattancherry channel (-55.20x106Kg), Cochin Gut (-237.6x106Kg), off Shipyard (-372.0x106Kg) and Bolghatty East (-52.8x106Kg), whereas gain is listed at Bolghatty West (232.8x106Kg). The net suspended sediment entering into the system (232.8x106 Kg) is less than that leaving the system (-717.6x106Kg). Eventhough the suspended sediment leaving the system is greater, the total transport through the estuarine system is very high (950.4x106Kg) during this season, in consistent with the monsoon dynamics. The higher values of the suspended sediments in the estuarine area during monsoon months suggest that the input of suspended sediments is mainly by fresh water runoff from land drainage. In addition, the tidal action (tidal bore) and the strong ebb currents as part of a stratified estuary during the monsoon season further accelerate the re-suspension of bottom sediments. The net suspended sediment transport during post-monsoon season was observed to be maximum at shipyard region (-199.2x106Kg), but at Bolghatty East and West region, the net transport is minimum (19.20x106Kg & -2.40x106Kg). In Mattancherry Channel and Gut region, the values of net transport of suspended sediments are -26.40x106kg and 38.40x106Kg respectively. In this harbour, only purpose oriented dredging is being held during the post-monsoon season, where riverine inflow and tidally driven flow almost balance each other as the estuary show features of a partially mixed condition. 9.0 Conclusions The sediment transport computation in the coastal and estuarine environment of the Cochin estuary is described above. Based on the case study, the computation of net suspended sediment transport in Cochin estuary was computed during the three seasons and it 69
show that there is a net loss of suspended sediment during monsoon (-717.60x106 Kg) as well as during post-monsoon seasons (-266.4x106Kg) and a net gain during pre-monsoon season (436.8x106Kg). The above values, the estimated annual net suspended sediment budget for this harbour is approximately -547.2x106kg which indicates a net annual loss of suspended sediment from this system. The suspended sediments are not consistently lost (except for dredging held for reclamation works) but eventually deposited in nearby areas apart from oscillating to and fro with currents and tides within the marine as well as riverine reaches. References 1. Dyer,K.R. (1973). Estuary – A physical introduction, John Wiley, 140p. 2. Kamphuis, J .W., Davies, M. H., Nairn, R. B., and Sayao, O. J. (1986). Calculation of littoral sand transport rate, Coastal Engineering, 10, 1-21. 3. Kamphuis,J.W. (1991). Alongshore sediment transport rate, Journal of Waterways, Port, Coastal and Ocean Engineering, ASCE, 117(6), 624-641. 4. King, D.B. (2005). Influence of grain size of the sediment transport rates with emphasis on the total longshore rate. U.S. Army Corps of Engineers. pp-24. 5. Lakshmanan, P.T, Shynamma, C.S. Balchand A.N, Kurup.P.G and Nambisan, P.N.K. (1982). Distribution and seasonal variation of temperature and salinity in Cochin backwaters, I.J.M.S., pp 170-172. 6. Pritchard, D. W. (1967). What is an estuary: physical viewpoint". In Lauf, G. H. Estuaries. American Asso. Adv.Sci., Publ. 83. Washington, DC. pp. 3–5.
7. Singh, I.B. (1980). Depositional sedimentary environments. Springer-Verlag, New York, pp 9-12. 8. Soulsby, R. (1997). Dynamics of marine sands- A manual for practical applications. Thomas Telford, 249p. 9. Srinivasan, K. Revichandran, C. Maheswaran, P.A. Mohammed Asharaf.T.T and Murukesan, N. (2003a). Propagation of tides in the Cochin estuarine system, south west coast of India. IJMS, 32, pp 14-24. 10. UdayaVarma, P.U. Pylee, A and Raju, V.S.R. (1981). Tidal influence on the seasonal variation in current and salinity around Willingdon Island. Mahasagar, 14, pp 225-237. 11. U.S. Army Corps of Engineers (1984). Coastal Engg. Research. Shore Protection Manuel (3rd Ed). 12. van Rijn,L.C. (1985). Sediment transport. Part 1: Bed load transport. Part II. Suspended 70
QGIS 13. sediment transport. , J. of Hydraulic Engg. 110., Publ. No 334.
TRAINING MANUAL By Integrated Coastal and Marine Area Management (ICMAM) Project Directorate, Ministry of Earth Sciences, Government of India
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Quantum GIS (QGIS) Quantum GIS (QGIS) Quantum GIS (QGIS) is a powerful and user friendly Open Source Geographic Information System (GIS) that runs on Linux, Unix, Mac OSX, and Windows. QGIS supports vector, raster, and database formats. QGIS is licensed under the GNU Public License. The Quantum GIS project was officially born in May of 2002 when coding began. The idea was conceived in February 2002 when Gary Sherman began looking for a GIS viewer for Linux that was fast and supported a wide range of data stores. That coupled with an interest in coding a GIS application led to the creation of the project. In the beginning Quantum GIS was established as a project on Source Forge in June 2002. July 6, 2002, and the first, mostly non-functioning release came on July 19, 2002. QGIS Features QGIS is a cross-platform (Linux, Windows, Mac) open source Geographic Information system and consists of • QGIS Desktop - The classic QGIS desktop application offers many GIS functions for data viewing, editing, and analysis. • QGIS Browser - A fast and easy data viewer for your local, network and online (WMS) data. • QGIS Server - A standard-compliant WMS 1.3 server that can be easily configured using QGIS Desktop project files. • QGIS Client - A web front-end for your web mapping needs based on OpenLayers and GeoExt. QGIS Desktop The major features include 1. Direct viewing of vector and raster data in different formats and projections. Supported formats include: PostGIS and SpatiaLite, Most vector formats supported by the OGR library, including ESRI shapefiles, MapInfo, SDTS and GML. 72
Raster formats supported by the GDAL library*, such as digital elevation models, aerial photography or landsat imagery, GRASS locations and mapsets, Online spatial data served as OGC-compliant WMS , WMS-C (Tile cache), WFS and WFS-T 2. Mapping and interactive exploration of spatial data. Tools include: on-the-fly reprojection, print composer identify/select features edit/view/search attributes feature labeling vector diagram overlay advanced vector and raster symbology 3. Create, edit and export spatial data using digitizing tools for vector features field and raster calculator and georeference 4. Perform spatial analysis such as map algebra, terrain analysis and hydrologic modeling, network analysis 5. Publish your map on the internet using QGIS Server or the "Export to Mapfile" capability and Customize QGIS through the extensible plugin architecture. QGIS can be downloaded and installed from http://www.qgis.org/ Using QGIS – Basics and Hand-on exercises In this session you will learn how to Use QGIS interface Add data layers Change data symbology Create and export a map From the Desktop click on QUANTUM GIS icon and the main window opens up.
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1.0 Starting QGIS, adding and removing data From the Desktop click on QUANTUM GIS icon and the main window opens up.
3
4 1
5
2
6
There are 6 major areas of QGIS main screen (Figure 1): 1. Table of Contents (layers) on the left 2. Map Overview Area 3. Standard Menu System 4. Zoom and other tools in the button row 5. Map area at the center (blank right now) 6. Status bar (area at the bottom of the application screen) The status bar provides information spatial extent, Scale and Current coordinates of cursor 2.0 Menu QGIS has a standard menu system: 1. File > New Project, Open Project, Save Project, Save Project As ..., Save As Image, Export As Mapserver file, Print, Exit 2. View > Zoom full, Zoom to selection, Zoom to layer, Zoom last, Refresh, Show bookmarks, New bookmark, Toolbars
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3. Layer > Add a Vector Layer, Add a Raster Layer, Add a PostGIS Layer, Add a WMS layer, Remove Layer, New Vector Layer, In Overview, Add All To Overview, Remove All From Overview, Hide All Layers, Show All Layers 4. Settings > Project Properties, Custom Projection, Options 5. Plugins > Plugin Manager 6. Vector > Creating vector from external source, analysis and processing 7. Rastor > Georeferencing, Terrain analysis, projections, conversion and analysis. 8. Database > Data base management. 9. Web > Metadata search 10. Processing > Toolbox, history and log, Graphic modular, Option, Results Viewer and commander. 11. Help > Help Contents, QGIS Home Page, Check QGIS version QGIS Icons File Toolbar New Project
Creates a new QGIS Project
Open a Project
Opens an existing QGIS Project
Save Project
Saves the current QGIS Project
Save Project As
Saves the current QGIS Project with a different filename
New Print Composer
Creating new layout
Composer Manager
layout and printing capabilities
Map Navigation Pan the Map
Pans the map
Pan Map to Selection
Move to selected features
Zoom In
Click or “drag a box” by holding mouse button to zoom in 75
Zoom Out
Click or “drag a box” by holding mouse button to zoom out
Zoom Actual Size
Zoom to 1:1 Scale level
Zoom to Full Extents
Zoom to the full extent of all layers in the map
Zoom to Selection
Zoom to selected feature
Zoom to Layer
Zoom to active layer
Zoom to last Extent
Zoom to the previous extent
Zoom to next Extent
Zoom to the next extent
Refresh Map
Refresh the map view
Manage Layers Add a Vector Layer
Adds a vector data layer to the map
Add a Raster Layer
Adds a raster data layer to the map
Add a Post GIS Layer
Adds a Post GIS Layer to the map
Add SpatiaLite Layer
Adds layers from a SpatiaLite database
Add MSSQL Spatial Layer
Adds layers from a MS SQL database
Add Oracle Spatial Layer
Adds layers from the Oracle database
Oracle Spatial Georaster
Adds Raster from the Oracle database
Add WMS/WMTS Layer
Adds layers from the WMS server
Add WCS Layer
Add WFS Layer from WCS Client 76
Add WFS Layer
Add WFS Layer from a Server
Add Delimited Text Layer
Add Tabular data to the map
Create a new vector layer
Creates a new editable vector layer
Create new GPX Layer
Create GPX layer from GPS Observation
Click on features to identify them
Lists attributes of the selected feature
Select Features
Select Features by rectangle, Polygon, freehand and radius
Deselect Features
Deselect all selected features
Select features using an expression
Select feature using an mathematical expression
Open Attribute Table
Open a layer’s attribute table
Field Calculator
Calculate length, area and geometry
Measure a line
Measures distance – Click multiple times to combine multiple segments, Right click to end
Measure an area
Measures area – Click multiple times to create polygon, Right click to end
Measure an angle
Measures angle – Click to draw the first segment of the angle you wish to measure
Map Tips
Map display tips
Attributes
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New Bookmarks
Create a new spatial bookmark
Show Bookmarks
Displays list of available spatial bookmarks
Text annotation
Write text in the map window
Current Edits
This feature allow the digitization of multiple layers
Toggle Editing
Click to begin editing the active layer
Save Edits
Save editing the active layer
Capture Point
Click to capture point features
Capture lines
Click multiple times for nonlinear lines, Right click to end
Capture polygons
Click multiple times to create polygon, Right click to end
Node Tool
Select Multiple vertices at once and to move, add or delete them together.
Delete selected
Click to delete the selected feature
Cut selected feature
Click to cut selected feature(s)
Copy selected feature
Click to Copy selected feature(s)
Digitizing
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Click to paste selected feature(s)
Paste selected feature
Using QGIS QGIS is a tool for viewing, querying, editing, composing and publishing electronic maps. It combines functionality for electronic mapping and spatial analysis. For those of you who have seen or used the ArcView 3.x product, it's quite similar.
Start QGIS The main window will be blank; this is an empty default project. 1. Main Menu > project > Click Project Properties in the main menu. The
Project
Properties window will appear. 2. Click on the General tab at the top of the window and set Project Title and Map Units. Call this project Training and set the Map Units to Decimal degrees. 3. To set the projection of the project, click on the projection tab and find Geographic Coordinate System Universal Transverse Mercator (UTM) -> and WGS 84. 4. Click
button to make changes.
5. First we will add a vector file. 6. Click on Add a Vector Layer button or select Layer -> Add a Vector Layer in the main menu. Go to C:\trg\. Double left click on the file named Landuse.shp 79
Now let's display the raster file. 7. Click on Add a Raster Layer button or select Layer -> Add a Raster Layer in the main menu. 8. Select the uthandi.img file from your working directory and click 9. You have two overlaying layers now in QGIS.
10. If you don't have the raster image in your view, then select any layer in the Table of Contents (TOC) and click the Zoom to layer menu button. The view should refresh itself and you will be able to see two data layers. Click on the raster file mss.img and drag it down so that it is listed in the table of contents BELOW the land use vector layer. You should see the 80
raster image covered with the land use layer. The order that layers appear in the TOC is the order that they will be drawn on the map. 3.1 Adding New Layers 1. We have added one vector layer and the raster layer to the view. 2. Use the Add a Vector Layer button to add the other data layer (roads.shp) from C:\trg. 3.2 Change TOC information Let's change the Table of Contents references: 1. Right click on Landuse layer rename it as luse.shp. 2. Change the color of this polygon layer to unique values. a. Right click on the layer and select Properties b. Click on Style tab c. Select Categorized in top of the tab, select the attribute for Column tab and then click the classify button. d. Click the button to accept a default scheme of random colors. For more specific color and outline options, you can try using the additional outline and color options in this menu. e. Also, adjusting the Transparency slider at the top of the menu will allow you to see the image below.
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3.3 View Attribute Data To look at the associated attribute table for the Landuse theme: 1. Select the landuse Layer in TOC by clicking on the layer’s name. 2. Click on Open Attribute Table button. 3. Scroll to the right to view various records of data 4. Scroll down and select any record. The associated polygon will be highlighted in yellow on the map. 5. Selecting a polygon on the map with the Select Features
tool will also highlight
the corresponding row in the attribute table. 6. Another way to see attribute information for a specific spatial feature (polygon, in our case), use Feature ID tool. 7. Click on the Feature ID
tool and then click on a feature (in the active layer) you
are interested in. 8. A window containing information for
this feature will appear. Note that it has the
same fields as the attribute table.
3.4 Measuring distances Let's measure the distance between objects on the map. We will use the Measure Tool for this operation. 82
1. Click on the Measure tool. 2. Place a cursor over a feature and left click with a mouse to set a starting point. Select another point and click again. A window showing segments' length will appear 3. The results will be in the map units you are working in. In this case, meters. 4. Continue to measure or right-click to stop. 5. Use the same process with the Area Measure tool, to measure the area of a polygon. 3.5 To save an image of the map 1. Click Project > Save As Image 2. A dialog window will appear. You will need to specify a file name and location, as well as the desired image format. JPEG and PNG are widely supported formats which can be used in text documents or presentations.
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Exercise I: Georeferencing the Remote Sensing Data Image rectification is an important procedure for many image processing applications. Simply put, it is the process of converting a raw image into a specified map projection. The procedure involves the selection of distinguishable ground control points (GCP's) in the image, such as road intersections. These points are then assigned the appropriate reference information, such as latitude/longitude or UTM coordinates. This reference data can be obtained from existing map sheets or from fieldwork utilizing global positioning systems (GPS). After a certain number of GCP's have been entered and referenced, the computer program resamples the original pixels into the desired projection. The importance of rectification is that the image can now be used in conjunction with other data sets. For example, the rectified image could be opened in a Geographic Information Systems (GIS) program such as ArcView. Since the image is now in a certain map projection, it should line up perfectly with other projected layers of data, such as political boundaries, land use, soil types, road networks, drainage systems, etc. If the image was collected recently, the information could be used to update outdated GIS layers. The rectified image could also be used as the reference source for image-to-image registration. 1. FILE--SAVE PROJECT in C:\trg\inundation.gps. Now, to open the inundation.gps, select FILE and OPEN PROJECT. This will bring up the Open Project window. Navigate to C:\trg\ and double click on inundation.gps to open the project. 2. The satellite data is stored in C:\trg\uthandi.jpg. And here’s the raster map loaded into QGIS;
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3. Raster > GEOREFERENCER which can be used to georeference images. Go to click on “GEOREFERNCER”. Opening up the georeferencer, brings up a georeferencer window Use the “OPEN RASTER” icon and load the image to be georefernced from C:\trg\uthandi\uthandi.jpg. Open the raster; you can zoom into the area into which you want to put control points. You want to have the highest zoom that the map’s still clear, as the accuracy of your final map depends on how well you placed control points. Four junctions have been selected as GCPs and their coordinates are tabulated below. Intersections as my control points. Choose a pixel on the map in the georeferencer, and a dialogue comes up, wherein the coordinates have been filled in and the coordinates, you can enter in the boxes. Once finished click OK, you have your first control point: Point 1: Upper left: lat.12.874983°, lon.80.235997° Point 2 : Upper right : lat.12.875008°, lon.80.255217° Point3: Lower Left: lat.12.863247°, lon.80.236541° Point4: Lower right : lat. 12.863467°, lon.80.255030° The other GCPs are added one by one. QGIS’s “Zoom Previous” is really useful for flipping between scales on both the plug-in window and the main map. The GCPs can be saved using the “Save GCP Points As …” every now and then. After collecting the necessary GCPs, Transformation Settings have to be specified before running the gereferencing process. There are lots of options here Transformation Type: Linear is useful if you’re just adding georeference data to an already computer generated map. Helmert is a simple shear/scale/rotate transformation. The various Polynomial types will correct more gross distortions, but need many control points and can be processor intensive. Thin Plate Spline will distort your map locally to match GCPs. Resampling Method: This controls how the output pixels are calculated. Nearest Neighbour is quick and blocky, but useful if you’re mapping an image that has sharp transitions. Cubic 85
maintains more detail, while applying some smoothing at the cost of some detail loss and a fair bit of processing power. Compression: This controls the file size of the output GeoTiff file. JPEG and Deflate can result in small files, but there’s a chance that other GIS systems can’t read the data.
Once you hit “Start Transformation”, QGIS will create your referenced image.
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Exercise II Create a vector file for the village boundary Open the project file :C\trg\inundation.gps On-Screen digitization On-screen digitizing of shapefiles is generally performed on a background satellite image or scanned toposheet that is included as an image Theme in the View. First, select the background image that will be used for visual referencing, and then add it as a Theme in the View where digitizing will be done. The georeferenced cadastral map should first be added to the view. Add the image layer by clicking on the ADDLAYER icon. Navigate to c:\trg\uthandi_cadastal.img and the image layer is added in the view. A vector polygon layer is to be created to digitize the landuse parcels from the imager layer. Use the “NEW SHAPE FILE” icon to create a polygon shape file by changing the shapefile type to POLYGON. The new shape file require a name and so navigate to d:\temp and type boundary.shp as the name of the new shape file. Boundary.shp will now be added as a new theme above the image layer.Use “ADD NEW SHAPE FILE” to digitize the polygons from the cadastral image. Every click using the above icon will produce a vertex and the polygon is digitized bytracing the boundary of the village as seen in the image layer.
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Exercise III Digitizing the Cadastral Map Repeat the above exercise and create a new file C:\trg\cadastral.shp and digitize all the land parcel boundaries in the cadastral image layer. The survey numbers of each parcel is added in the table. Every feature created (point, line or polygon) in QGIS will have a record associated with and stored in the feature attribute table. In order to identify each feature, it is necessary to give a unique id number for each feature that is digitized. This id number or usually referred to as the label is added in the table. Make the landparcels.shp as the active theme by simply clicking on its name in the Table of contents and say TOGGLE EDITING. Open its corresponding table by right clicking on the name and select ATTRIBUTE TABLE EDITOR from the menu. The attribute table of landparcels.shp will open up. Click on NEW COLUMN icon. Create a new field by giving a NAME and defining the type of the field data. Create a name PARCELNO, Type – Integer and Width – 3 and the new field will now be added to the table. The table is now in the edit mode and corresponding survey number can now be added in the table. After adding all the values choose APPLY and close the table. The survey nos and now stored in the table and as a part of the landparcels.shp. 88
Exercise IV Creating Landuse map of the study area Landuse map of the study area is to be prepared using satellite data pertaining to the study area, stored in d:\training\uthandi\uthandi_rec.tif. Add the rectified images stored in c:\trg\uthandi_rec.img to the view using the “ADD RASTER LAYER” icon. A vector polygon layer is to be created to digitize the landuse parcels from the imager layer. Use the “NEW SHAPE FILE” icon to create a polygon shape file by changing the shapefile type to POLYGON. The new shape file require a name and so navigate to c:\trg and type landuse.shp as the name of the new shape file. Landuse.shp will now be added as a new theme above the image layer. Make the landparcels.shp as the active theme by simply clicking on its name in the Table of contents and say TOGGLE EDITING. Capture individual polygons using the CAPTURE POLYGON icon. Complete a polycon by double clicking on the end point. Open its corresponding table by right clicking on the name and select ATTRIBUTE TABLE EDITOR from the menu. The attribute table of landparcels.shp will open up. Click on NEW COLUMN icon. Create a new field by giving a label and defining the type of the field data. Create a name NAME, Type – String and Width – 25 and the new field will now be added to the table. The table is now in the edit mode and corresponding landuse class can now be added in the table. After adding all the values choose APPLY and close the table.
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Create a new filed CLASS and add the landuse for each polygon. The following classes can be identified from the satellite imagery namely water bodies, dense settlements, sparse settlements, vegetation, sandy areas etc.
Double click on landuse.shp in the table of contents. A Layer properties comes up. Under STYLE select CATEGORIZED and a colouring scheme is displayed.
Now select the field used to colour the theme using the COLUMN field and select Name from the attribute table. Click APPLY and OK and the theme will be displayed as per the various landuse classes as enetered in the attribute table.
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Exercise V Generating the Area of inundation from field data The data on the run-up levels collected from the field using GPS is transferred and stored as a database file in C:\trg\ runup.shp. Add the shape file runup.shp as a theme in the view. Create a new polygon shape file by joining the maximum inundated points measured from the field and the shoreline from the image.
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Exercise VI Plotting of High Tide Line and the CRZ buffers Add the HTL line to the imagery The High Tide Line was created using the data provided by the Department of Environment, Govt. of Tamil Nadu. The HTL line is stored as a shape file in u:\trg\htl.shp. htl.shp will now be added to the View indicating the extent of the area under the high tide line in the imagery.
Buffer Generation A buffer is a polygon defining the area within a specified distance of some other feature.
Select
GEOPROCESSING
VECTOR
–
TOOLS
–
BUFFER from the Menu bar. To create a buffer at a uniform specified distance In the create buffer dialog box select htl.shp as the feature of a theme and enter 200 for the buffer distance and save the output file in the directory. This would create a buffer at a uniform specified distance of 200m all around the HTL.
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Exercise VII Overlaying the Elevation Contour In order to identify the coastal areas vulnerable to tsunami it is important to get the elevation contours of this area. The elevation contours are used in association with the field observation on inundation collected during the 2004 tsunami to identify the areas vulnerable to the tsunami hazard. Use the “OPEN RASTER” icon and load the georeference image of the study area from c:\trgi\uthandi_rec.img. Use the “OPEN VECTOR” icon and load the elevation contours from c:\trg\contours.shp. Use the “OPEN VECTOR” icon and load the inundation points from c:\trg \inunda_pts.shp
By overlaying the elevation contours and the inundation points it is evident that those areas that are below 3.5m are the most vulnerable.
By using the 3.5 contour line as the reference the areas between this contour and the shoreline can be identified as the area's most vulnerable to the tsunami.
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Exercise VIII Creation of the final composite map on Inundation in the study Creation of the final composite map on Inundation in the study The final composite maps should show the maximum extent of inundation of seawater on the observations made in the study area during the tsunami of 26th December, 2004, with respect to the landuse, elevation contours, HTL and cadsatral survey nos. Open a new view and add the following themes on landuse, cadsatral map, HTL,run-up levels and elevation contours • C;\trg\landuse.shp • C:trg\cadastral.shp • C:\trg\htl.shp • C:\trg\run-up1.shp • C:\trg\contours.shp
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Exercise IX Georeferencing satellite image for Pichavaram field visit
Open QGIS Desktop Goto menu
Select Raster
Select Add Raster layer button
click Georeferencer
browse image file from folder
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after adding image file
zoom to control point position
select add point button
enter coordinates values in Enter map coordinates display appear
1
79°46'26.91"E
11°26'59.75"N
2
79°48'5.12"E
11°27'1.26"N
3
79°46'39.93"E
11°24'51.85"N
4
79°48'24.44"E
11°24'52.30"N
After giving four coordinates goto settings click Transformation button select transformation type select resampling method select compression technique select output folder select output projection then click ok… projected image loaded in QGIS 96
Exercise X Importing ground truth points to QGIS environment Goto Main menu, click on plugins and enable GPS tools.
Select
GPS tools icon. GPS tool windows appears Browse
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Load GPX file
GPS tools window appears which is loaded with features and highlights various data (Waypoints, Routes and Tracks) Deselect routes and tracks, so that only Waypoints are downloaded Select OK 98
99
Save the files one after the other by right clicking Save vector layer as Format : ESRI shapefiles Format Save as: save in desired folder CRS : WGS 84 Select OK
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Save as
Concepts and Policies of Integrated Coastal Zone Management Dr. K. Ajith Joseph Senior Scientist and Executive Director Nansen Environmental Research Centre (India) 6A, Oxford Business Centre, Sreekandath Road, Ravipuram, Kochi-682016 Email:
[email protected]
1.0 Introduction The protection and sustainable utilization of marine resources in the coastal zone(s) has become an issue of great scientific concern to marine scientists as well as policy makers and administrators of every nation. In the context of land-ocean interaction, coastal zone is defined as extending from the coastal plains to the outer edge of the continental shelves, approximately matching the region that has been alternately fooded and exposed during the sea level fluctuations of the late quaternary period [IGBP, 1993). A major section of people depends on their livelihood in this region however some section concentrate their activities in this region towards global tourism, industrialization, agriculture, etc., resulting in an alarming increase of coastal population density. As an example, coastal population accounts for 90% of the land-based pollutants like sewage, industrial wastes, nutrients and toxic materials. The anthropogenic influence on the coastal zone has over the years accentuated the transport of sediment flux to the coastal waters compared to natural flux rates, with the exception of certain regional scenarios. The impact of functioning of reservoirs, river management strategies and freshwater diversions in the upstream reaches (Ajith et al., 1995) has brought about vast alterations in the downstream.
The coastal zone is one of intense and dynamic in nature and is often subjected to societal demands for space and natural resources, and to external natural and human influences. Societal demands outpace the capacity of the coastal zone to provide the desired goods and services. An uncontrolled use of the resources in the coastal zone can lead to an excessive and unsustainable utilisation of renewable and non renewable resources like fisheries and minerals and degradation of environmental quality and health of coastal ecosystem potentially making hazardous consequences to human health and property. Integrated 101
Coastal Management (ICM) has been identified by many nations as the most appropriate process for determining the combination of outputs and services that are produced in order to ensure sus- tainable use of the resources (Le Tissier et al., 2003). The Rio UNCED Conference in 1992 was a prelude to the protection and sustainable utilization of coastal zones and has discussed this item as an issue in its Agenda 21 (Chapter 17) about the need for increased awareness of the socio-economic importance of coastal marine environments. According to Agenda 21, despite national, sub-regional and global efforts, current approaches to the management of marine and coastal resources have not always been proved as capable of achieving sustainable development, and the coastal resources and coastal environment are being rapidly degraded and eroded in many parts of the world . Hence it recommends, each coastal state should consider establishing, or where necessary strengthening, appropriate coordinating mechanisms for integrated management and sustainable development of coastal and marine areas and their resources, at both local and national levels (Ajith and Balchand, 2000).
Fig.1. ICZM policies and guidelines (Source: Baba, M. 2003) According to Pathak and Sinha (2000) the alarming growth in anthropogenic activities in the coastal areas have generated tremendous stress upon natural ecosystems which needs an attention for their proper management and a legislation was established by Govt. of India 102
called Coastal Regulation Zone as a framework for land use plan as well as that for the linkage between the coastal population and the coastal zones. In this context, Pathak et al. (2001) observed that the in recent years, the emphasis of coastal planning and management is on conservation of natural resources for which an integrated approach is essential together with the sustainable use of coastal resources. This approach is considered as a way point towards the Integrated Coastal Zone Management (ICZM) which is defined (CAMP Network, 1989)as a dynamic process in which a coordinated strategy is developed and implemented for the allocation of environmental, social, cultural and institutional resources to achieve the conservation and sustainable multiple use of the resources in the coastal zone.
2.0 Integrated Coastal Management The definition of Integrated Coastal Management (ICM) was given by the Joint Group of Experts on the Scientific Aspects of Marine Environmental Protection (GESAMP) in 1996 (GESAMP, 1996) as it is a dynamic and continuous process by which progress towards sustainable use and development of coastal areas may be achieved.
Integrated Coastal Management (ICM) has been identified by many nations as the most appropriate process for determining the combination of outputs and
services that are
produced in order to ensure sustainable use of the resources. To be effective, ICM plans should acknowledge the following substantive principles of sustainable development (Le Tissier et al.,2003) that development is necessary for the satisfaction of basic human needs and aspirations by maintaining the ecological integrity within the limits of ecological carrying capacity. ICM plans should also give due weightage to equity and social justice while considering the per capita use of resources within and between nations and generations. Similarly ICM plans promote public participation and their involvement in decision making processes while government regulations are implemented for private as well as corporate sectors inorder to promote environmentally sound use of the natural resources.
Hence
Integrated Coastal Management results in the improvement of the quality of life of human communities who depend on coastal resources while maintaining the biological diversity and productivity of coastal ecosystems. Similarly it also include a concept of holistic management whereby the ICM process must integrate administrative with community structures, science 103
with management, and sectoral with public interests, and provide a mechanism for the management of both resources and resource users of the coastal zone. Integrated Coastal Zone Management rather seeks to develop a capacity inorder to build a framework to engage in a process for approaching the management of issues, activities and uses that orginate from the coast in the broadest sense. Management of the coastal zone requires an input of knowledge and an understanding of the dynamic processes of natural and social systems. In order to understand how problems arise, and why they are important, the natural sciences are vital to understanding ecosystem function and the social sciences are essential for elucidating the interplay with the human dimensions that place demands on the system. This integration enables more appropriate solutions to be found.
3.0 Major issues in the Coastal Zone
Population explosion in the Coastal zone demands for economic growth that leads to competition for resources which accentuate the degradation of environment and the society which outperforms the benefits of development and modernization.
Major issues in the coastal zone are Over-exploitation of renewable resources, either directly by harvesting or by the destruction or modification of habitats and disruption of predator/prey and other ecological relationships, Conflicts that arise where several hu- man activities that depend on the same area and/or resource are incompatible, and Insidious damage that may result from cumulative impacts of different practices, including loss of biological pro ductivity and diversity.
Similarly, Coastal Hazards and
Livelihood security are other
concerns in the coastal zone
4.0 Policy guidelines- Coastal Regulation zones The initial Policy framework for the protection of coastal zone of India was developed in 1981 to keep 500m from the High Tide Line free from all developemental activities followed with the resolution of Environmental Protection Act (1986) with a draft notification of on Coastal Regulation Zone (CRZ) in 1986. Subsequently CRZ notification
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was issued in 1991. Meantime, National and State Coastal Zone Management Authorities were formulated in 1998.
CRZ classification follows that the coastal stretches within the 500 m of HTL on the land ward side are classified under four categories to regulate the developmental activities, which often degrade the coastal environment. Ecologically sensitive areas like national land parks/marine parks, sanctuaries, reserve forests, wildlife habitats, mangroves, coral reef, areas close to breeding and spawning grounds of fish and other marine life, areas rich in biodiversity, areas of outstanding natural beauty/historical/heritage areas, inter-tidal areas and other areas which are under the threats of sea level rise due to global warming comes under the category, CRZ-I. Already developed areas within the municipal limits or in other legally designated urban areas which have already substantially built up to or close to the shoreline with drainage and approach roads, water supply and sewerage main facilities are designated under CRZ-II. Whereas the relatively undisturbed areas in the coastal zone in the rural areas within municipal limits or in other designated urban areas which are not substantially built and those which do not belong to the above two categories are classified under CRZ-III. But the areas that are undesignated under the above three categories which belong to coastal stretches of small island territories like Andaman and Nicobar, Lakshadweep and small islands comes under CRZ-IV category. Hence the coastal states and union territory administration shall prepare `Coastal Zone Management Plans
by
identifying and classifying the CRZ areas with their respective territories in accordance with the guidelines designated for CRZ (I,II,III & IV regions) and obtain approval of the Central Government in the Ministry of Environment and Forest (MEF). For the interim period, all developmental activities in the CRZ shall be regulated by the State Government within the framework of guidelines issued and shall not violate the provision of the norms until the CRZ plans are finalized.
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Fig.2. Schematic diagram for CRZ after Ajith and Balchand(2000)
Later on 2011, M.S.Swaminathan committee recommendations were made based on a participatory approach to cover the Coastal zone for land and water environment and mentioned that the responsibility of implementation bestowed with the local self governments. MoEF (2011) has issued guidelines for the preparation of integrated island management plan and Island Coastal Regulation zone and the salient guidelines are listed as follows: 1. The land area falling between the hazard line and 500mts from HTL on the
landward side, in case of seafront and between the hazard line and 100mts line in case of tidal influenced water body the word ‘hazard line’ denotes the line demarcated by Ministry of Environment and Forests (hereinafter referred to as the 106
MoEF) through theSurvey of India (hereinafter referred to as the SoI) taking into account tides, waves, sea level rise and shoreline changes. 2. No developmental activities other than those listed in this Notification shall be
permitted in the areas between the hazard line and 500mts or 100mts or width of the creek on the landward side. The dwelling unit of the local communities, tribals including that of the fishers will not be relocated if the dwelling units are located on the seaward side of the hazard line. The Union territory Administration will provide necessary safeguards from natural disaster to such dwelling units of local communities. 3. All the existing roads including the internal roads shall be strengthened, as these
roads shall serve for the purpose of livelihood, communication, rescue, relief and evacuation measures during natural hazards. Similarly, the Guidelines for development of beach resorts or hotels in the designated areas of ICRZ-III and ICRZ-II/IIMPs for occupation of tourist or visitors with prior approval of the Ministry of Environment and Forests are issued (2011) and only the main points are listed here as follows: I. Construction of beach resorts or hotels with prior approval of MoEF in designated
areas of ICRZ- II and III for occupation of tourist or visitors shall be subject to the following conditions, namely:(a). The project proponent shall not undertake any construction within 200 metres in the landward side of High Tide Line and within the area between Low Tide Line and High Tide Line; (b).The proposed constructions shall be beyond the hazard line or 200mts from the High Tide Line whichever is more.
5.0 Summary The concepts and policies of ICZM are aimed at protecting and sustainably managing the coastal and marine resources of a country. This can be achieved through awareness creation among stakeholders through capacity building with the aid of state of the art tools like Geomatics and Satellite remote sensing. However the success of policy implementation is bestowed on each individual on a consensus basis evolved by means of public participation. 107
References Ajith Joseph K., Rasheed K. and Balchand A. N., 1995. Impact assessment on tropical estuarine characteristics in relation to river management approaches. IAPSO Symposia, Hawaii (Abstract only-PS O5, 117) Ajith Joseph K., Balchand A. N., 2000. The application of Coastal Regulation Zones in Coastal Management- Appraisal of Indian Experience. Ocean and Coastal Management Journal, Elsevier. Vol.43/6. pp. 515-526. IGBP. In: Pernetta JC, Milliman JD, editors. LOICZ}Global change, land}ocean interactions in the coastal zone: implementation plan. IGBP Report No. 33, Stockholm, 1993, p. 1}215. Le Tissier, M.D.A., Ireland, M., Hills, J.M., McGregor, J.A., Ramesh, R. and Hazra, S (eds). 2003. A Trainers’ Manual for Integrated Coastal Management Capacity Development. 187pp. The University of Newcastle upon Tyne, Newcastle upon Tyne, UK. Pathak, M.C., Ranjay Sinha, R.Nigam, A.R.Gujar and Kotnala, K.L., 2001. . Concepts, Approaches and Applications of Integrated Coastal Zone Management in planning and Management of India coast. Proceedings of National seminar on Four decades of marine Geosciences in India- A retrospect. GSI. Mangalore., 202-205.
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Coastal Processes, Coastal Erosion, and Application along Indian Coast Dr K V Thomas Academic Consultant, KUFOS Email:
[email protected]
1.0 Introduction The coastal zone of India is characterised by diverse morphological features such as sandy beaches, coastal plains, headlands and promontories, earth and rocky cliffs, mudflats, paleo mudflats, deltas, tidal flats, raised beaches, pocket beaches, barrier beaches, sand dunes, salt pans, estuaries, creeks, bays, tidal inlets and islands. It also harbours very sensitive ecosystems such as mangroves, corals, sea grass, salt marsh, mudbanks and lagoons. Numerous structures such as harbor breakwaters, seawalls and groins have become part of the costal systems emerging as artificial morphologies. There are more than 100 rivers, which bring large quantities of sediments to the coast. The major ones are the Ganges, Brahmaputra, Mahanadi, Krishna, Godavari and Cauvery on the east coast and Narmada and Tapi on the north-west coast. The total length of the coastline including that of the Andaman and Nicobar and Lakshadweep islands is more than 7500 km out of which the length of the coast around Andaman and Nicobar and Lakshadweep islands is about 2100 km. A recent study using satellite imageries by Space Application Centre (Rejawat et al 2015) has reported the total length of the coast line as 8414 km out of which the length of the coast around islands is 2636 km. In certain sectors the coast is highly inundated with creeks and promontories while the coast is straight in certain other sectors. The coastline has been undergoing physical changes throughout the geological past. Although the last tectonic phase in the Indian peninsula has been one of the general emergence, the present coastal geomorphology of India has evolved largely in the background of the post-glacial transgression over the pre-existing topography of the shore, coast and offshore zones. The Holocene sea fluctuated in the course of the last 6,000 years and the marked regression is indicated between 3,000 to 5,000 years B.C.
The continental shelf is narrow along the east coast. On the west coast, the wide shelf of about 340 km of the north tapers to less than 60 km in the south. With a monsoon climate, the southwesterly winds during the period from June to September bring high waves closer to the southwest coast. The east coast generally becomes active during the cyclones of the northeast monsoon period (October-November). The tidal range also varies significantly from south to north. While the southern coast, have a tidal range of less than 1 m, the northwest peaks at 11 m and the northeast reaches 4 m.
2.0 Coastal processes Coastal processes along the Indian coast are controlled by the waves and currents associated with the Southwest and Northeast monsoons. Coastal and nearshore morphology plays an equally important role in deciding the impact of the natural forces and the nature of interaction between the terrestrial and marine systems. Other than tsunami, the wind induced waves are the major driving force triggering various coastal processes. The wind waves undergo refraction and shoaling as it interacts with the bottom topography when these travel towards the coast through shallow waters. Refraction causes bending of waves resulting in convergence and divergence of wave energy. Shoaling causes gradual decrease in wavelength and increase in wave height and reaches a condition of instability when the waves break before reaching the coast. In general the waves break when the ratio of wave height to water depth reaches 0.78. Wave breaking releases its energy which drives the surf zone dynamics in the form of longshore currents and on/off shore currents including rip currents. These are confined to the surf zone. The surf zone dynamics also generates edge waves and infra gravity waves.
Longshore currents could be either upstream or downstream depending on the wave direction and shoreline orientation. Many a times, especially during monsoon, the surf zone currents attain the form of cell circulations which is a combination of longshore currents and rip currents. The wind, breaking waves, tides, longshore and on/off shore currents together induces sediment transport both as suspended and bed load. Sediment transport of a coastal region is confined to and within the sediment cell in the form of distribution and redistribution of sediments. Sediment transport during monsoon occurs similar to storm events where cross shore transport is important. The sediment transported offshore gets temporarily deposited as longshore bars in the
nearshore which later moves onshore under favourable wave conditions, mostly during the post monsoon season. The monsoon does not occur as a continuous process but have a few breaks in between. The wave activity will also have a few highs and lows during the monsoon and the sediment transport pattern follows storm events associated with monsoon breaks and reactivation.
3.0 Coastal erosion
The combined energy of winds, waves, tides and currents shapes the coastal regions by moving the material in the coastal and nearshore regions. The landward displacement of the shoreline caused by these forces is usually known as coastal erosion. In the process subaerial landmass is lost to the sea or the hinterland. Changes in relative sea level and the geomorphological characteristics of the coast are other factors are also contributing factors. Another major factor is anthropogenic interventions such as construction of artificial structures like harbor breakwaters, groins, seawalls, reclamation, mining of beach sand, offshore dredging, and building of dams across rivers. Shoreline changes induced by erosion and accretion are natural processes that take place over a range of time scales. They may occur in response to short-term events, such as storms, regular wave action, tides and winds, or in response to long-term events due to sea level variations and tectonic activities that cause coastal land subsidence or emergence. Most coastlines are naturally dynamic, and cycles of erosion are often an important feature of their ecological character. In the case of earth cliffs, erosion occurs in the form of episodic events associated with slumping of cliffs.
The Central Water Commission (CWC) has estimated that about 1248 km (23%) of shoreline along the Indian main land is affected by various degree of erosion varying from minor, moderate to severe as on 2005. A recent study by Space Application Centre (Rejawat et al 2015) showed that 3829 km (45.5%) of the coast is under erosion, 3004 km (35.7%) is getting accreted, while 1581 km (18.8%) of the coast is more or less stable in nature. Highest percentage of shoreline under erosion is in the Nicobar Islands (88.7%), while the percentage of accreting coastline is highest for Tamil Nadu (62.3%) and Goa has the highest percentage of stable shoreline (52.4). The analysis shows that the Indian coast has lost a net area of about 73 sq. km
during 1989–1991 and 2004–2006 time frame. In Tamil Nadu, a net area of about 25.45 sq. km has increased due to accretion, while along the Nicobar Islands about 93.95 sq. km is lost due to erosion.
As per the CWC records about 480 km along the Kerala coast is affected by erosion as on 2005. At the same time the study by Rejawat et al 2015 using satellite images says that out of a total coastal length of 586 km of the Kerala coast, the eroding coast is about 218 km and the accreting coast is 294 km. It also says 74 km is stable. According to National Centre for Sustainable Coastal Management (NCSCM) out of the 588 km of the Kerala coastline, 370 km (63%) is eroding, 141 km (24%) is accreting and 46.3 km (8%). Another 31 km (5%) is rocky and stable. The discrepancies in the values are because of the data sources used and the tools adopted.
4.0 Causes of coastal erosion
Natural and anthropogenic interventions or a combination of both induce coastal erosion. Natural causes are wave action, tides, wind, storms, nearshore currents, slope processes (slumping of cliff), sea level rise, in addition to catastrophic events like tsunami and storm surges. Mudbank dynamics such as its occurrence, migration and disappearance is another natural process that triggers and modifies erosion along the Kerala coast. Anthropogenic causes include construction of inappropriate, improperly designed, built, or maintained harbours, groins and jetties in the nearshore, dredging of tidal inlets and harbor mouths, construction of seawalls and revetments, destruction of beaches, mangroves, corals and other natural buffers, mining of beach sand and neasrshore material, land reclamation, and construction of tidal barriers and upstream dams.
One of the major shore destabilizing activity along the Kerala coast is the construction of major ports and fishing harbours. Kerala has one major port at Kochi and 20 fishing harbours. Another 5 fishing harbours are in the process of development. Vizhinjam international port is another major construction activity coming up. Severe erosion along Chellanam-Kannamali sector south of Kochi tidal inlet is attributed to capital and maintenance dredging and disposal being carried out for the Kochi and Vallarpadam port facilities. It is also found that all the fishing harbours have caused significant erosion on one side of the harbor and accretion on the other side. The
upcoming Vizhinjam International port is one of the largest interventions in the coastal zone of the country in the form of breakwater of about 3.18 km and outer approach channel of 2 km. About 66 ha of nearshore is also to be reclaimed for Phase 1. Experiences with the other small fishing harbours constructed suggest that major morphological changes may occur along the coasts with the construction of Vizhinjam port.
5.0 Coastal protection and coastal management
In broad terms, coastal erosion management techniques can be hard stabilization (engineering structures), soft stabilization (beach replenishment, artificial dunes, coastal vegetation) or natural methods (retreat, relocation of facilities). Hard stabilization includes shore parallel structures such as seawalls, revetment, gabion revetments, detached offshore breakwaters, submerged breakwaters, artificial headlands, and shore armouring. Groins and jetties are the common shore normal structures. The most basic function of hard structures is to intercept and dissipate the energy of waves and currents and associated sand transport; to protect the shore against erosion; and to protect the shore against sliding (cliffs). The hard structures normally induce end erosion at the downstream side, accretion in the upstream side and cause scouring on the seaward side in addition to impediments to shore based fishing activities and tourism.
Soft measures include mangrove/marine vegetation, marine fencing (thatch wood and brush fencing), artificial nourishment, artificial reefs with soft materials, sand bypassing and sand bag structures as a temporary protection measure. These help to sustain natural morphology and ecosystems to function as natural support to the coast. Artificial nourishment requires regular replenishment and measures to retain the sediments. Bypassing of sediment is done where erosion is due to hindrance to the movement of sediments from one side of a structure to the other side. Reefs help to develop a natural fish habitat around the structures. Artificial reefs can also be designed to facilitate surfing.
6.0 Coastal Regulation Zone
The understanding that development of the coastal zone within a controlled management framework could help protecting the coast led to the Coastal Regulation Zone (CRZ) notifications of 1991 and 2011. It provides a buffer zone for the coast where activities detrimental to coastal stability are controlled. It prevents destruction of coastal morphology and ecosystems such as sand dunes, beaches, mudflats, mangroves and corals which are natural protection to the coast. Activities which do not require shore frontage are prohibited in the defined coastal regulation zone. Environmental Impact Assessment and Environment Management Plan are made mandatory for construction of ports and coastal protection structures. By controlling activities in the coastal zone and close to the shoreline, the coastal zone will be decongestised, the impact of coastal erosion on property will be curtailed and the impact of coastal structures on sediment buffer and transport will be minimized. The strict implementation of CRZ will help control the coastal erosion and its adverse impacts on the community and coastal system. The Coastal Zone Management Plan of 1995 based on which the regulations are being implemented is being re-prepared following the guidelines of CRZ 2011.
7.0 Use of geomatics in the study coastal process and coastal management
Delineation of shoreline, High Tide Line and Low Water Line to study shoreline changes can be efficiently carried out using multidate remote sensing data in GIS environment. Mapping of different coastal morphologies and ecosystems to understand the changes over different periods could also be done in this format. The availability of high resolution remote sensing data and GPS with better accuracies have given better resolution to the shoreline change maps being produced. The different satellite images being used for shoreline change study are IRS 1A, IRS IB, Landsat TM 5, SPOT I and SPOT 2 are being used to delineate shore line from 1985 to 2000. These satellites have a spatial resolution of 20 to 30 m. Better resolution satellites such as IRS IC, IRS ID and IRS P6 provide data with accuracies ranging from 23.6 to 5.8 m. Cartosat 1 and Cartosta 2 give data products with spatial resolution of 2.8 and 0.80 m.
Different shorelines such as Still Water Line, High Water Line, Low Water Line, High Tide Line and Vegetation Line are identifiable in the field. The most easily identifiable feature corresponding to shoreline from imagery is wet-dry boundary which is equivalent to High Water Line in the field. The maps are normally generated in 1:50000, 1:25000, 1:5000 (cadastral) and 1:4000 (cadastral) scales. The most difficult part is accurate matching of satellite imageries to cadastral maps. This is overcome by georeferencing the cadastral maps using accurate GPS/DGPS data at precisely locatable Ground Control Points (GCPs) in satellite images. Cadastral maps and satellite images are rectified in the same geographical coordinate system and projection and superimposed in GIS platform. One of the major contributors to the errors is those occurring while reproducing the map from original map through photocopying and scanning. While photocopying the enlargement or reduction produce the scale error; also the shrinkage/folding of paper during the process. Another is the scale error during geo-referencing the map. It may be noted that cadastral maps have no projection while the images are projected. When overlying cadastral map on image by applying a common coordinate system, some distortions do occur at edges and in the shape of features such as road network, plot boundary, etc. The errors in reproduction of cadastral maps can be minimized by taking proper precautions. The errors in georeferencing could be controlled by taking precautions through selection of proper field GCPs and identifying the field GCPs in the cadastral as well as satellite images precisely. And by making some finer adjustments, the ecosystem boundaries delineated from satellite images could be matched with real cadastral boundaries on the ground.
A case study is also presented in delineating shoreline and ecosystem/ morphology boundaries for understanding coastal processes.
Ministry of Earth Sciences Integrated Coastal and Marine Area Management (ICMAM) Project Directorate Kerala University of Fisheries and Ocean Studies (KUFOS) Nansen Environmental Research Centre, India (NERCI) Training Programme on
Geomatics for Coastal Zone Management (18-22, April, 2016) Monday (18/4/2016) Season I 9.30 -11.00
Registration & Inaguaration 11.00 -11.15 Tea Break
Season II 11.15 -12.45
Concepts and Policies of ICZM (Dr. Ajith Joseph, NERCI) Coastal Zone management of Kerala (Dr. Kamalakshan Kokkal, KSCSTE, Govt.of Kerala)
Tuesday (19/4/2016) Coastal Processes, Coastal Erosion, and Application along Indian Coast (Dr.K.V.Thomas, KUFOS)
Circulation & Sediment Transport – a Case Study (Dr. Rasheed, ICMAM)
12.45 -14.00 Lunch Break Season III 14.00 -15.30
Season IV 15.45 -17.15
Geomatics of Coastal Zone Management (S.K.Dash, ICMAM)
Fundamentals of Remote Sensing & Image Processing (M.Iyyappan, ICMAM)
15.30 -15.45Tea Break Fundamental of Coastal Smart Phone GIS and QProcesses GIS Hand on session (Dr. Rasheed, ICMAM) (G.Gopinath, ICMAM)
Wednesday (20/4/2016)
Thursday (21/4/2016) Marine Pollution-An overview
Friday (22/4/2016)
(Dr.G.V.M. Gupta, (Prof,N.R Menon KUFOS) CMLRE) 11.00 -11.15 Tea Break
Field Visit (To study in Coastal Zone/ Use of GPS for field data Collection)
GPS Data Downloading and CRZ mapping using open source Q-GIS Hands on session (G.Gopinath&M.Iyyappan ICMAM)
Concept and Application of Integrated Coastal Zone Management
(Dr. P.Madeswaran, ICMAM) 12.45 -14.00 Lunch Break
Ecosystem Modelling- SW Coast of India (V Ranga Rao, ICMAM)
Geomatics for ICZM (Dr. Tune Usha, ICMAM)
15.30 -15.45 Tea Break Ecosystem Modelling- SW Feedback & Coast of India Valedictory (V Ranga Rao, ICMAM)
