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INTERNATIONAL JOURNAL OF GEOMATICS AND GEOSCIENCES Volume 4, No 3, 2014 © Copyright by the authors - Licensee IPA- Under Creative Commons license 3.0 Research article ISSN 0976 – 4380

Comparison of Multi-criteria evaluation (AHP and WLC approaches) for land capability assessment of urban development in GIS Bamshad Shenavr1, Seyed Mohsen Hosseini2 1- Graduated MSc, Environmental Department, Science and Researches Faculty, Islamic Azad University. 2- Natural Resource and Marine Science Faculty of Tarbiat Modares University. P.O.BOX: 46414-356, Noor, Mazandaran, Iran [email protected]

ABSTRACT Background and aims Occurring the environmental problem, in different dimensions, is result from not observing the environmental considerations and criteria in locating new cities.Since the environment has a limited ecological potential for human uses ,the ecological potential assessment provides a well suited bed for environmental planning thus The main purpose of this article is to compare different criteria based on librarian studies and expert opinions and determining suitable criteria to determine proper criteria by applying multicriteria decision-making Methods for land capability assessment to establish new cities. Methods: In this research, multicriteria assessment approach includes Weighted Liner Composition(WLC) and Analytic Hierarchy Process (AHP) are utilized in ecological potential assessment of Zardrud basin of Khouzestan Province for urban development by using geological information system (GIS) based on 13 criteria which includes: slope, evaluation, aspect, rainfall, average temperature, land type, soil, land use, distance to river, distance to industries, distance to road, earthquake bearing and fault zones. Land capability map is developed in which it shows prioritized and proper areas for urban development in the aforementioned range. Conclusion Research results show that most import ants factors on urban development were earthquake bearing, land use and soil and show that northern, part of zard basin and in the terms of political partitions Ghale Tol of central part of Baghmalek town is of the most rank in urban development. Results obtained from this study can be used as a pattern to be utilized for urban planner and designer in order to well suited urban location with respect to observing the environmental considerations. Keywords: WLC, AHP, Land Capability Assessment, GIS, Urban development 1. Introduction Environmental protection requires balance between development and natural resources area.

Submitted on October 2013 published on March 2014

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Comparison of Multi-criteria evaluation (AHP and WLC approaches) for land capability assessment of urban development in GIS Bamshad Shenavr, Seyed Mohsen Hosseini

Land capability assessment is a process that has trying through the human relationship with nature, and worthy of development in harmony with nature can provide. Land capability importance as a decisive stage, a large part of the construction costs and other economic planning projects, it has the attention of managers and decision making. According to the limited ecological environment for human use, land capability assessment can the core of environmental studies for the prevention of crises, provides a good platform for environmental planning. Ecological capability evaluation in recent years in Iran as well as a necessity in land use planning has been proposed and in the local programs of economic, social and cultural Islamic Republic of Iran has been manifested. Urbanization is a continuous process and it is important to identify suitable housing areas for future development. Urbanization is now a common feature of all third world countries. Environmental problems in different dimensions, resulting from the non-compliance with environmental considerations and criteria in the site selection of new cities and direction of urban development. Expansion of cities without the program has been the source of many problems and crises of the environment. A obverse side of urban development, prosperity and other adverse effects of accelerated development, and without the program. In this study, the application of standards consistent with environmental considerations have been made to determine the criteria and weighting pattern and compare different criteria based on librarian studies and expert opinions and determining suitable criteria in order to evaluate the environmental potential to establish new cities to achieve urban permanent development having the least Adverse effect at present and in the long term. The aim of this paper was determination of a new framework for site selection of new cities with environmental consideration with Multi-criteria evaluations (MCE) and utilizing Analytical Hierarchical process (AHP) and WLC in ecological potential assessment of khuzestan zard basin for urban development in GIS environment. 2. Material and methods 2.1 Study area Understanding the natural features of the study area can be important in determining the structures constructed in public places and places more safety be effective also in development. Study area includes part of the basin of the Zard Khuzestan. Therefore, to investigate, within the following areas of R11 and R10 and R 9 and R8 and R7 and R6 and R4 and R3 classify and study separately each of these areas .Terms of geographical area under study central part of city Baghmalek is located. The land investigated in research located in Baghmalek (Khouzestan province) and has the area of 514 square kilometers between latitudes of 31°20´and 31°31´N and between longitudes of 49°42´ and 50°10´E at Up-stream of Jareh Dam.This area of 8 sub, small and large has been established that the area of R 6 with 3.39 square kilometers, the smallest sub-zones in the basin is considered. subsequent natural basin in the north, mountains and plains and forest and mountains and in the south is dry. River, Zard River from north to south, covered with branches after Abolabbas(Mongasht), Golal and near the village of Zard River valley about seasonal and several branches (Mazhin) and downstream of the dam Jareh River joins exquisite. Regional weather conditions and relatively diverse in terms of altitude under different climates, which leads to high levels of diversity is good. With annual dominant wind direction during the year rose in the southwest are evaluated. Industrial zone including crushing, asphalt unit, factory spaghetti, pump house, No. 3, Industrial Estate Baghmalek the central part of city Baghmalek are International Journal of Geomatics and Geosciences Volume 4 Issue 3, 2014

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Comparison of Multi-criteria evaluation (AHP and WLC approaches) for land capability assessment of urban development in GIS Bamshad Shenavr, Seyed Mohsen Hosseini

located. In the Zard River the most polluted rivers around the city Baghmalek the epicenter population of the region is seen. Baghmalek in several points around the city sewage directly into rivers and makes a lot of pollution and contamination when water is added. Figure (1) shows the study of area.

Figure 1: Map of study area in Iran 2.2 Method In this study, according to the desired goal of library procedures (documents) and field studies have been used. Field studies include visits to the study area to identify the natural features, vegetation status, and region were taken with GPS ground control points from topographic maps at 1:25000 scale geological map of block 77 Ramhormoz and scale of 1:100000 (geological and mineral exploration), and map natural resources and land units (land capability) with the scale of 1:100000 (Department of natural Resources Khuzestan province) has been used. Classification map of slope, aspect and altitude of a digital elevation model (DEM), the main map, the distance from the industries and the distance from the river using existing topographic maps are provided. Mapping the digital elevation model (DEM) from the 1:25000 scale topographic using Microstation V.8.1 software and maps from the menu under Export to XYZ coordination of all information to a txt file and then using the converted ArcGIS software and software using the IDW digital Elevation Model (DEM) was constructed in the region. The layers of software into the environment, then they became Shape format to use in their software. UTM system, the image was considered equal for all layers. Determine the weights of criteria (impact layers of both) and also determine the classes of each layer of information (weight of the a layer) to design a questionnaire completed by the experts concerned. This stage of the weighting of the software Expert Choice has used. After determining the weights in the Attribute Table, all the layers field as weight was added, and the weights of each class of the information entered. Then to called final layer of the Query in the software ArcGIS was used. Weights determined using software criteria in table (1) are shown. 2.3 Multi-criteria decision making (MCDM) Multi-criteria decision making (MCDM) or Multi-attribute decision making (MCDA) interchangeably used. Issues based MCDM usually associated with a set of options used is based on the conflicting and inconsistent been evaluated to be word criterion (criterion) is International Journal of Geomatics and Geosciences Volume 4 Issue 3, 2014

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Comparison of Multi-criteria evaluation (AHP and WLC approaches) for land capability assessment of urban development in GIS Bamshad Shenavr, Seyed Mohsen Hosseini

considered as a general term that the concepts of attributes (attribute) and goals (objectives) (objective) is included from so many different aspects of MCDM can be divided into two general classes: Multivariate decision making (MADM) multi-objective decision making (MODM). In multivariate analysis, decision making (MADM) also select the best options, the options seem to be appropriate, specified, or options to be ranked in a descending order of priority and the options will be a priority. In decision models Multi Objective (MODM) unlike linear programming (which has only one goal) are faced with multiple objectives. Approaches based on MODM, the decision criteria (objective) and the decision variables are laid Methods of MADM to the method of (simple additive weighting method), (value / utility function approaches) and (analytical hierarchy process), (ideal point method) (concordance methods) pointed out. Therefore, according to the description and purpose of this study, and comparisons using weighted linear combination (WLC ), the operations can be assessed and the Analytical Hierarchy Process (AHP) for weighting and fuzzy method (Fuzzy), was used for standardization of criteria that describe each of these methods continue to be paid. The availability of GIS and Multi-criteria decision making (MCDM) methods allow combining knowledge derived form different sources to support land use planning and management. 2.4 WLC (Weighted linear combination) Weighted linear combination, or simple additive weighting, is based on the concept of a weighted average in which continuous criteria are standardized to a common numeric range, and then combined by means of a weighted average. This method is based on the weighted average. This component is used as a compensatory models and scoring and scoring models are subgroups. GIS overlay process for the combination of factors and limitations of a method that uses weighted overlay process. The method can be executed using any GIS system with overlay capabilities, and allows the evaluation criterion map layers to be combined in order to determine the composite map layer which is output. SAW techniques can using the GIS overlay capabilities are invested, are performed. The methods can be implemented in both raster and vector GIS environments. Some GIS systems, e.g. Idrisi, have built-in routines for the WLC method, and there are available freeware modules or scripts, e.g. for ArcGIS to perform that kind of MCDA of this sort. The method of weighted linear combination (WLC) in a GIS environment Operations can be assessed for urban development, the WLC method is used. When the overall scores were calculated for all options, the option is selected with the highest overall score. In this method for evaluating the value of each alternative or option, or Ai following formula is used. Table (1) process weighted linear combination method shows.

suitability Map = ∑[ foctor map ccn]* weight( wn) * constra int(bo / .1) Cn: Cells by standard raster layer Wn: Weights obtained from AHP method B0/1: Restriction maps using Boolean In this research, each criterion or sub criterion was weighing using pair wise comparison method and to selecting the preferred criteria, the preference’s value table of the Saaty is used. To ease the calculating of the weights in purpose of preference degrees and hierarchies the Expert choice software was used. To applying the weighted linear combination (WLC) method, the following steps were performed: Determining of evaluation criteria collection (in form of map layers) and total score of each option International Journal of Geomatics and Geosciences Volume 4 Issue 3, 2014

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Comparison of Multi-criteria evaluation (AHP and WLC approaches) for land capability assessment of urban development in GIS Bamshad Shenavr, Seyed Mohsen Hosseini

Standardizing and converting of scale of values (evaluation criteria), Determining the weight of criteria i.e. weight and relative importance of each criterion and layer information Generation of weighting standardizing map layer Generation of final map usages and determining of total score overlaying maps and union function on standardized weighing map layers 2.5 Normalization (standardization) with fuzzy Set the suitability values of the factors to a common scale to make comparisons possible and it is hard to compare different things. Most indicators have been different scales and they are conflict with each other. Some indicators are positive aspects and some negative aspects. Therefore, in order to compare the different scales of measurement should be no scaling (normalization) can be used. Various indices, and significant sums are dimensionless and so are classes that can be compared with them. Fuzzy Membership Functions are used to standardize the criterion scores. The fuzzy membership values higher, higher compliance and lower membership values, the lower their compliance. Among the known functions from the Sigmoidal, Linear and J-Shape named. Another factor in determining the threshold is fuzzy maps of standardization that they are called control points. Each of the functions in the ArcGIS environment and then programming on any Map layers were applied. 2.6 AHP methods There are many factors to be considered in making a decision on urban land use. Existing methods are mostly qualitative and all factors are considered descriptive which cannot be quantified therefore, it is difficult to analyze the integrated impact of all these factors. Analytic Hierarchy Process (AHP) is considered an effective approach to quantify the qualitative factors, thus the integrated impacts of these factors can be obtained in quantitative terms. This method hierarchical process (AHP) was developed in 1980 by saaty. Weight determined in accordance with this method compare to that of both criteria. The paired comparison method to compare the relative importance of criteria in a continuum is divided into 9 class .In this method, after identification criteria, must weigh the relative importance of each criterion in relation to the desired target can be determined. AHP is a mathematical method for determining the priority of the process and criteria in the evaluation process and decision making. The main reason is that the AHP helps decision makers to a complex problem into a hierarchical structure to break and then pay to solve it .The AHP analysis of the nature of transparent and clear rationale for selecting the various options creates. Ease of use and multilateral cooperation of the various methods, thinking, reasoning and the efficiency and improves group decisions. In this study, the Consistency Ratio (CR) of the matrix of paired comparisons is 0.06. 2.7 AHP Conceptual model pattern to Land Capability Assessment for Urban Land use in GIS In this conceptual model for finding the most suitable locations for new cities using weights obtained from AHP method is presented in GIS software. Conceptual model of decision-making process in the AHP model is done in 5 levels below which includes:

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Comparison of Multi-criteria evaluation (AHP and WLC approaches) for land capability assessment of urban development in GIS Bamshad Shenavr, Seyed Mohsen Hosseini

Level 1: The main objective of general hierarchy: finding the best location for the establishment of new cities are at the highest level. Level 2: determining of main criteria for selecting the suitable location of new cities: Criterion 5 of the land form, climate, ground, environment and access-buffer has been selected. Level 3: determining of Sub-criteria: Level 3 includes the following 15 criteria that included :Land(slope, elevation, aspect)Climate(mean rain mean temperature),Ground(geology, soil),Environment(land use planning),Access-Buffer(river, road and network transport ,industry, fault, earthquake). Level 4: A three-storey scale: Given the different nature of their parameters, it is difficult to compare them to the couple. Criteria to reduce the number of elements and a comparison of a three-storey classification is used.(good, medium. poor) Level 5: Different options for site selection: Modeling based on the total space allocated to the regular networks and values for all criteria before they are calculated. Therefore, cell size and area, a large number of candidate models is in place. 3. Results 3.1 Comparison of criteria weights One of the important results of this study is related to criteria and weights that are obtained according to experts and library studies. The criteria for earthquake prone areas, land use, soil faults, geology and slope, respectively, have had more weight than other criteria for urban development. 3.2 The final model of WLC Based on the weights and layers of a map created using the fuzzy method, the weighted linear combination model for evaluation of urban development can be achieved. Therefore, increasing the number of parameters and its implementation in other areas can be optimized for the same conditions. WLC:[earth] * 0.2373 + [re-ab3] * 0.0138 + [re-aspect3] * 0.0155 + [re-baran3] * 0.0274 + [re-dem3] * 0.0095 + [re-disfalt3] * .1206 + [re-geo3] * 0.0725+ [re-karbari3] * .163 + [resanayea] * .0225 + [re-slop3] * .059 + [re-soil3] * .2175 + [road-asli] * .0394

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Comparison of Multi-criteria evaluation (AHP and WLC approaches) for land capability assessment of urban development in GIS Bamshad Shenavr, Seyed Mohsen Hosseini

Diagram 1: WLC and fuzzy method procedure for land capability assessment for urban land

Diagram 2: The hierarchal structure of assessing land capability for urban land use International Journal of Geomatics and Geosciences Volume 4 Issue 3, 2014

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Comparison of Multi-criteria evaluation (AHP and WLC approaches) for land capability assessment of urban development in GIS Bamshad Shenavr, Seyed Mohsen Hosseini

Table 1: Major criteria and minor criteria to locate new cities

0.020605 0.0061275 0.001767 0.1080 0.03214 0.00926 0.2013 0.05987 0.01726

0.723 0.215 0.062 0.723 0.215 0.062 0.723 0.215 0.062

Good Medium Poor Good Medium Poor Good Medium Poor

Weight

Sub-criteria

Weight

0.055

slope L1

0.08

Main criteria Land form

0.0095

Elevation L2

0.0185

Aspect L3

0.0265

Mean rain c1

0.033

Climate

0.0095

Mean temparatureC2

0.0665

Geology G1

0.290

Ground

0.1875

Soil G2

0.1075

LAND USE E1

0.163

Environment

0.0205

River A1

0.434

AccessBuffers

0.0425

Road and network transport A2

0.0285

Industry A3

0.1495

Fault A4

0.2785

Earthquake A5

Goal

Assessing Land Capability for Urban Land use

Final Compare weight weight criteria 0.0397 0.723 Good 0.011825 0.215 Medium 0.00341 0.062 Poor 0.0068685 0.723 Good 0.00204 0.215 Medium 0.000589 0.062 Poor 0.0133775 0.723 Good 0.0039775 0.215 Medium 0.001147 0.062 Poor 0.0191596 0.723 Good 0.0056975 0.215 Medium 0.001643 0.062 Poor 0.0068685 0.723 Good 0.0020425 0.215 Medium 0.000589 0.062 Poor 0.04807 0.723 Good 0.01429 0.215 Medium 0.004123 0.062 Poor 0.1355 0.723 Good 0.040312 0.215 Medium 0.011625 0.062 Poor 0.07772 0.723 Good 0.02311 0.215 Medium 0.0066 0.062 Poor 0.01482 0.723 Good 0.004407 0.215 Medium 0.001271 0.062 Poor 0.0307275 0.723 Good 0.00913 0.215 Medium 0.00263 0.062 Poor

4. Conclusion and discussion The land suitability map was divided into five classes: most suitable, suitable, moderately suitable, poorly suitable, and unsuitable. Table 4 shows that comparing between AHP and WLC methods for the Urban Land use suitability and urban development. AHP method has the highest percentage in the “Suitable” with 36.72% of the study area and WLC method, the highest percentage in the’ Moderately suitable’ with 43.10% of study area. At both methods, the lowest percentage of class is ‘Unsuitable’. The results show that the separation sub-zones International Journal of Geomatics and Geosciences Volume 4 Issue 3, 2014

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Comparison of Multi-criteria evaluation (AHP and WLC approaches) for land capability assessment of urban development in GIS Bamshad Shenavr, Seyed Mohsen Hosseini

that The AHP method, the largest area the sub-zones of the R4 and R10 is a poorly suitability capability and Minimum Area, R11 and R10 sub-zone with the unsuitability capability. The WLC method, the largest area under the R11 and R10 sub-zones with moderately suitability and a minimum area of about R9 and R7 sub-zone capability is unsuitability. R3 sub-zone, the results of both methods shows that the greatest area of capability is unsuitable and Eastern and northeastern parts are not suitable for urban development. In order to prioritize areas the final map, all of pixels, the Natural breaks through class 5 very good, good, moderate, low and very low with the AHP method was developed and applied in layers ultimately limits the fault, earthquake areas, slope, forest ,height and privacy restrictions the final map of can be obtained through Boolean methods. Overall, the watershed in terms of political divisions, Ghale tol district of the city Baghmalek central part of urban development is the highest priority. Table 2: Statistical analysis comparing between AHP and WLC methods for the urban land use suitability map class Most suitable

WLC 10554

Area(hectare) AHP 14076

Suitable Moderately suitable Poorly suitable Unsuitable

11024 22221 6455 1211

18913 11525 4005 2990

Area (%) WLC AHP 20.7 27.33 21.41 43.10 12.44 2.35

36.72 22.38 7.77 5.8

Figure 4: The final urban development site selection map obtained from WLC method International Journal of Geomatics and Geosciences Volume 4 Issue 3, 2014

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Comparison of Multi-criteria evaluation (AHP and WLC approaches) for land capability assessment of urban development in GIS Bamshad Shenavr, Seyed Mohsen Hosseini

Figure 5: The final urban development site selection map obtained from AHP method

Figure 6: The final urban development site selection map obtained from Boolean method International Journal of Geomatics and Geosciences Volume 4 Issue 3, 2014

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Comparison of Multi-criteria evaluation (AHP and WLC approaches) for land capability assessment of urban development in GIS Bamshad Shenavr, Seyed Mohsen Hosseini

Based on the model parameters in order to locate suitable areas for urban development in the watershed zones was implemented Zard Khuzestan. The results show that the spatial information system a great tool for analysis and planning support in space. The analysis and results can be any of the following priority areas, the survey can be divided in two parts ie each sub-watershed areas and the entire province has been zard. The results of this study using Analytical Hierarchy Process (AHP) and WLC to evaluate the environmental watershed level has been established. Can be used as a model of macro management in order to in accordance with the development plan consistent with environmental principles and to improve management policies used at the macro level. The most important issue in the method used, proper selection of weights and optimum use of the data layers, so that lack of proper weight in decision making despite the use of multiple data layers, the results will be inappropriate to the times. GIS and WLC as analysis tools are valuable tools that can support the decision makers to find best possible urban development sites. The GIS analysis requires collecting data from different sources with different formats to create a complete uniform database. 5. References 1. Azar., A.Rajabzadeh., (2002), Applied decision making, Negahe Danesh publishes, Tehran, first edition. 2. Ahmad Al-hanbali J.,B. Alsaaideh,A. Kondoh, (2011), Using GIS-based weighted linear combination analysis and remote sensing techniques to select optimum solid waste disposal sites within Mafraq City, Journal of geographic information system, 3, pp 267-278 3. Asghapour M.J., (2004), Multiple Criteria Decision Making, University of Tehran Press, Third edition 4. Eastmen. J, R, (197), IDRISI for windows users guide, version 3.2, Clarc labs for cartographic technology and Geographic Analysis, Clarc university. 5. ESRI (2007). Using the conceptual model to create a suitability map. ArcGIS Tutorial. Accessed January 11, 2011webhelp.esri.com/arcgisdesktop/9.2/index.cfm?Topic Name= tutorials 6. Estoque C. (2011), GIS-based multi-criteria decision analysis, (in natural resource management), Ronald, D1 – Division of spatial information science, University of tsukuba 7. F.Makhdoum M.., (1987), A new method for analyzing and presenting data summarized in the process of land use planning, Journal of natural resource of Iran, (41), pp 68-78. 8. Feng C., Edwin H. W. Chan, (2004), Application of AHP in decision-making on urban land use: A case study of Chao-Hu city development in China,The International Journal of construction management, pp 93-110. 9. Karam., (2005), Land suitability analysis for the physical development in the northwest of Shiraz using multi-criteria evaluation approach in GIS, Journal of geographical research, Tehran, No. 54, winter, pp 93-106.

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10. Laskar,A., (2003),Integrating GIS and multicriteria decision making techniques for land resource planning, ITC University, MS in Geoinformation. 11. Makhdoum M.F, (2004), Environmental evaluation and planning by geographic information system, Tehran University Press, second edition 12. Malczewski J., (1999), GIS and multicriteria decision analysis.USA and Canada, John Wiley & Sons. 13. Mohamed A. AL-SHALABI, Shattri Bin Mansor, Nordin Bin Ahmed, Rashid Shiriff, (2006), GIS Based, Multicriteria, Approaches to housing site suitability assessment shaping the change, Munich, Germany, pp 8-13 14. Momeni M., (2006), New topic in operations research, Faculty of management, university of Tehran publishes, First edition. 15. Noori.,J.Jozi., (2002), Ecological capability evaluation of district 22 of Tehran for urban development, Journal of environmental science and technology, NO12, Spring, pp 33-43 16. S. Drobne et al)Samo Drobne and Anka Lisec, Jamova 2, SI-Ljubljana, Slovenia, Multi attribute Decision Analysis in GIS: Weighted LinearCombination and Ordered Weighted Averaging, Informatica 33 (2009) Informatica 33 (2009) 459–474 17. S.Mansor,B.,Ahmed,R.,Shiriff,M. Shalabi A.Al., (2006), GIS based multicrieria approaches to housing sit suitability assessment, Shaping the change, XXIII Congress, Munich, Germany. October, pp 8-13. 18. Saaty, T.L., (1980), The Analytic Hierarchy Process.,McGraw-Hill, New York. 19. Saaty, T.L., (1994), Highlights and critical points in the theory and application of the analytic hierarchy process. Eur. J. Oper. Res., 74, pp 426-447. 20. Saaty, T.L., (1995), Decision Making for Leaders: The analytic hierarchy process for decisions in a complex world. 3rd Edn., RWS Publications, Pittsburgh, PA. 21. Sarvar, (2004), Analytical Hierarchy Process (AHP) A new technique for location in geographical studies, Journal of geographical research, Tehran, Iran, No49, autoum, p19-38 22. Seyed Ali Jozi, Narges Zaredar and Sahar Rezaeian ,Evaluation of Ecological Capability using Spatial Multi Criteria Evaluation Method (SMCE) (Case study: Implementation of Indoor Recreation in Varjin Protected Area-Iran), International Journal of Environmental Science and Development, 1(3), pp 89-97.

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