trophic status

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Sep 10, 2002 - The intense extractions from the freshwater wells provoked the marine ..... Baluarte: located in front of the Cathedral with diffusion at 17 m depth ...
The University of Hull

The nutrient status and management of the Bay of Palma, Mallorca, Spain (EUROTROPH project) being a Dissertation submitted in partial fulfilment of the requirements for the Degree of

MSc in Estuarine and Coastal Science and Management

in the University of Hull

by

Francisco Javier Campuzano Guillén, Degree in Marine Sciences, University of Las Palmas de Gran Canaria, Spain

September 2002

In Memory of my father, Esteban Campuzano Moreno (1940-2002)

Acknowledgements.

Francisco Javier Campuzano Guillén has been supported by a grant of the Fundación Séneca, Centro de Coordinación de la Investigación, Comunidad Autónoma de la Región de Murcia (Spain). Additional expenses of fieldwork have been supported by the EUROTROPH project. I wish like to thank the support of my family, friends, classmates and lecturers during the difficult moments of this year, without their support I wouldn’t be writing this report. I would like to thank especially to Mike Elliott, my supervisor, the time employed in helping my English expressions. I wish like to thank as well, the cooperation for collecting information during my stay in Mallorca to the people of IMEDEA, IEO, the Environmental, Health, Tourism, Energy and Agriculture and Fisheries Departments of the Autonomous Community, as well as the people of the Local Authorities of the localities of Calvià, Palma de Mallorca and Llucmajor. I would like give thanks as well to my Mallorcan friends, without them this summer would have been completely different.

Table of contents:

Page

Chapter 1 Introduction.

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1.1. Nutrients in coastal areas. 1 1.1.1. Eutrophication: definition and classification. 1 1.1.2. Causes of eutrophication. 2 1.1.2.1. Nutrients. 2 1.1.2.2. Factors reducing herbivorous consumption of algae 3 1.1.2.3. Additional factors. 3 1.1.3. Symptoms of eutrophication. 3 1.2. The EUROTROPH Project. 4 1.3. Aim and objectives. 5 1.4. Sources of information. 6

Chapter 2 Study area background: the Bay of Palma .

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2.1. The Mediterranean Sea. 2.2. Nutrients in the Mediterranean. 2.3. The Balearic Islands. 2.4. The Bay of Palma.

7 8 9 10

Chapter 3 Abiotic and ecological features of Bay of Palma. 11 3.1. Hydrographical Study. 3.2. Climate characteristics of the area. 3.3. Air and Water temperature. 3.4. Salinity. 3.5. Water transparency (Turbidity). 3.6. Nutrients. 3.6.1. Nitrites. 3.6.2. Nitrates. 3.6.3. Phosphates. 3.6.4. Silicates. 3.6.5. Nutrient conclusion. 3.7. Oxygen saturation. 3.8. Chlorophyll a. 3.9. Zooplankton. 3.10. Marine vegetation. 3.10.1. Posidonia oceanica: Ecosystem role. 3.10.1.1. Basic Features of Posidonia oceanica meadows. 3.10.1.2. Organisms related to Posidonia oceanica. 3.10.1.3. Fate of Posidonia oceanica production. 3.10.1.4. Functional role of Posidonia meadows. 3.11. Land Hydrogeology.

11 13 15 15 15 16 17 18 20 21 22 25 26 27 28 29 29 29 30 31 31

Chapter 4 Human uses of the area.

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4.1. Residence and tourism. 4.2. Agriculture and farming. 4.3. Industry.

33 35 36

Chapter 5 Nutrient inputs on the Bay.

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5.1. Introduction. 5.2. Point source inputs. 5.2.1. Episodic inputs. 5.2.1.1. Torrent inputs. 5.2.1.2. Urban Waste Water Treatment Plants (UWWTP). 5.2.1.2.1. Palma I UWWTP 5.2.1.2.2. Other wastewater outfalls. 5.2.1.2.2.1. Urbanization S. C. El Dorado 5.2.1.2.2.2. Other UWWTP around the Bay. 5.2.2. Discharge inputs. 5.2.2.1. Palma II UWWTP. 5.2.2.2. S'Arenal UWWTP. 5.2.2.3. Bendinat UWWTP. 5.2.2.4. Desalination Plants. 5.2.2.4.1. Potabiliser of Son Tugores. 5.2.2.4.2. Bay of Palma desalination plant. 5.2.2.4.3. Other desalination plants. 5.2.2.5. Thermal Power Station San Juán de Dios 5.2.2.6. Marinas and boating activities. 5.3. Diffuse inputs. 5.3.1. Groundwater discharges. 5.3.2. Air inputs.

37 37 38 38 40 40 40 41 42 42 43 45 47 48 48 49 49 50 50 52 52 53

Chapter 6 Effects of the inputs on the Bay.

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6.1. Effects due to torrents inputs. 6.2. Effect of the UWWTP discharges. 6.3. Effects by desalination plants. 6.4. Impacts of boating activities. 6.4.1. Effects of boating. 6.4.2. Effects of the infrastructures and their maintenance. 6.5. Effects due to thermal emissions in the Bay of Palma 6.6. Conclusions. 6.6.1. Effects of nutrient inputs. 6.6.2. Eutrophication symptoms in the Bay of Palma. 6.6.2.1. Primary symptoms in the Bay of Palma. 6.6.2.2. Secondary symptoms in the Bay of Palma. 6.6.3. Conclusions.

54 55 56 58 58 59 61 61 61 62 62 63 64

Chapter 7 Enforcement of the EU Directives in the Bay of Palma.

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7.1. Introduction. 7.2. Nitrates Directive 91/676/EEC. 7.3. Urban Waste Water Treatment Directive 91/271/EEC. 7.4. Habitats and Species Directive (92/43/EEC). 7.4.1. Cap Enderrocat-Cap Blanc SPA-pSAC. 7.4.2. Cap de Cala Figuera SPA-pSAC. 7.4.3. Posidonia oceanica protection in the Balearic Islands. 7.4.4. Other protection designations. 7.5. Bathing Water Quality Directive (76/160/EEC).

65 66 67 70 71 73 73 74 75

Chapter 8 Bay of Palma management.

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8.1. Introduction. 8.2. The Spanish Government. 8.3. Balearic Autonomous Community. 8.4. Mallorca Island Government. 8.5. Municipalities. 8.6. Marinas and ports management. 8.7. Ecotourist tax.

79 79 80 80 80 82 82

Chapter 9 Final discussion and conclusions.

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9.1. Bay of Palma Nutrient Status. 9.2. Critique of the Study. 9.3. Suggestion for further work. 9.4. Recommendations.

83 84 85 86

Chapter 10 References.

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Abstract The entry of nutrient plants into coastal waters by different sources (anthropogenic or natural) can lead to nutrient over-enrichment (hypernutrification) or in the worst scenario to eutrophication, which is the sum of a series of undesirable changes in ecosystem structure and functions. By the end of the 1960’s the term “balearisation” (making reference to the Balearic Islands) was defined as a synonym for intensive and anarchy urbanisation in the shoreline. The case study, Bay of Palma, was the area more affected by this massive urban development, and as a consequence of this agglomeration, the demands of tourism facilities and production of wastes grew. The coincidence of a relative shallow and sheltered basin with reduced water exchange and the increase in nutrient inputs could lead to eutrophication phenomena. The Bay of Palma is a semienclosed neritic area located in the Southern coast of Mallorca (Balearic Islands, Spain), open to an oligotrophic sea (Mediterranean Sea), where permanent watercourses do not exist and marine dynamics are forced by the generally small coastal wind regime. This dissertation aims to find, identify and quantify the different sources of nutrients and their effects on the Bay of Palma, as well as relate them to qualitative impacts, estimate the ecological status of the Bay of Palma waters and analyse the repercussion of its management. The ecological status of the Bay of Palma can be divided in two areas: inshore waters and offshore waters. The inshore waters, presents generally characteristics of hypernutrified areas with some restricted water bodies presenting symptoms of eutrophication, such as the Port of Palma. The offshore waters were neither eutrophicated

nor hypernutrified, however was influenced by landbased nutrient inputs as well as by the outer water masses. Nutrient concentrations, and thus the ecological status, had some correlation with torrential inputs in the bay as well as, in the innermost waters, with anthropogenic inputs, especially from Urban Waste Water Treatment Plants and desalination plants.

Chapter 1.- Introduction. 1.1.- Nutrients in coastal areas. Many of the wastes entering the sea are plant nutrients. The entry of them by different sources into the coastal waters (e.g. by runoff with agricultural fertilisers, by untreated (or not enough treated) urban wastewater between the more common), enhances the growing of phytoplankton and fixed plants, benefiting some food chains by this enrichment (Clark, 1997). Although a moderate input may be beneficial, over-fertilisation results in very high production by plants and depletion in oxygen due to the decomposition of this high amount of organic matter by bacteria. Both excessive plant growth and oxygen depletion lead to alteration of the community structure, sometimes with serious consequences. These phenomena are features of eutrophication (Clark, 1997).

1.1.1.- Eutrophication: definition and classification. Eutrophication, as defined by the European Union in the Urban Waste Water Treatment Directive (91/271/EEC), means “the enrichment of water by nutrients, especially compounds of nitrogen and/or phosphorus, causing an accelerated growth of algae and higher forms of plant life to produce an undesirable disturbance to the balance of organisms present in the water and to the quality of the water concerned”. This definition gives the cause but also the symptoms of effect. The eutrophication definition differs from the one of hypernutriphication (Schramm & Nienhuis, 1996 from Elliott & de Jonge, 2002) which is regarded as “nutrient contamination - an excess of nutrients being present without adverse effects being manifest, the latter being the result of some other limiting factors”. Thus, when over-enrichment does not produce adverse effects the water body is hypernutrified and when adverse effects, known as symptoms, are present the situation is of eutrophication. Eutrophication can be divided, depending in the origin of the process, into natural and anthropogenic (man-made or cultural) eutrophication, being no significant difference between the final effects of both processes. Under natural conditions this is usually induced by upwellings and river discharges, hence the consequence is natural eutrophication. Anthropogenic or cultural eutrophication refers to the same process, but is 1

a consequence of pollution by sewage and related biodegradable effluents, agricultural fertilisers and polluted atmosphere; often these pollutants are combined in rivers with natural background loads of nutrients (UNESCO, 1988). However, time-controlled developments differ in both processes (UNESCO, 1988): 

Natural eutrophication is a relatively slow process (time scale 103-104 years) that allows evolutionary ecosystem adaptations to elevated trophic conditions;



Anthropogenic eutrophication introduces sudden changes (time scale 10 years or less) and hence non-compensated disequilibria, a stressed environment and possible substantial harm to living resources. In this report anthropogenic eutrophication, is considered for the Bay of Palma, so the

term “eutrophication” refers to anthropogenic eutrophication. Only those factors which society is able to control, at least indirectly, will be discussed.

1.1.2.- Causes of eutrophication. The following factors are considered relevant to an excessive primary production, and hence eutrophication:

1.1.2.1.- Nutrients:

Marine algae are normally exposed to an adequate supply of most elements, except nitrogen, phosphorus and silicon; considered as nutrients for the purpose of this work. Silicon may become limiting only for diatoms, meanwhile phosphorus and nitrogen are always of critical importance in relation to primary production. Phosphorus appears in the marine environment in particulate, colloidal and dissolved inorganic and organic forms. Orthophosphate, referred as to phosphate in this paper, is the form preferred by algae, although algae has the ability to utilise other forms (UNESCO, 1988) The most abundant form of nitrogen in seawater is dissolved molecular gas (N2) which occurs in concentrations almost tenfold the sum of particulate and dissolved inorganic nitrogen compounds. However, it does not enter biological processes, except in particular cases. In principle, ammonium are the form of nitrogen preferred by algae, and only when ammonium concentrations are depleted to < 0.15 μmol N/l will nitrate and

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nitrite be used, in this order. There is evidence of partial utilization of various organic nitrogen compounds such as urea and amino-acids as the source of nitrogen for the algal growth, particularly in circumstances where the concentration of inorganic forms is becoming depleted (UNESCO, 1988)

1.1.2.2.- Factors reducing herbivorous consumption of algae.

Excessive biomass could develop in a less eutrophic system with moderate primary productivity, yet with reduced rates of herbivorous feeding, due to pollution by toxic metals, mechanical destruction of filtering organs of filter-feeders by high concentrations of solids in suspension, destruction of inshore or bottom hard substrata, oil spills or by destruction of benthic herbivores and filter-feeders by fisheries operations. (UNESCO, 1988)

1.1.2.3.- Additional factors.

Marine eutrophication is by and large a coastal phenomenon, that requires the coincidence a relative shallow and sheltered basin with reduced water, exchange, often subject to thermal or density stratification with one of the above factors (Fedra, 1988).

1.1.3.- Symptoms of eutrophication. When levels of nutrients (Phosphorus, Nitrogen and Silicon) are high enough phytoplankton blooms can develop, often developing red tides, which are large-scale phytoplankton blooms (Clark, 1997). Another over-enrichment effect is very high oxygen concentration in surface water due to increased photosynthesis by the dense blooms of phytoplankton. In addition, part of this high production falls to the seabed reducing the oxygen concentration in bottom waters and most benthic animals are killed or excluded from the area. This process is facilitated where a thermocline develops and the bottom water that receives the matter is cut off from atmospheric oxygen by the layer warm, less dense surface water floating over it (Clark, 1997).

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As Bricker et al (1999) summarised them, in an assessment for NOAA (US National Oceanic and Atmospheric Administration), symptoms can be divided into primary and secondary symptoms (Figure 1).

* SAV (Submerged Aquatic Vegetation) Figure 1. The simplified eutrophication model (Briker et al, 1999)

The presence or absence of these symptoms in the Bay of Palma will be discussed later on in this dissertation.

1.2.- The EUROTROPH Project. This work is part of the EUROTROPH Project which aims to improve the knowledge of the metabolic state (trophic status) of coastal ecosystems (EUROTROPH website, http://www.ulg.ac.be/oceanbio/eurotroph/). The main aim of this project is to determine the trophic status using simultaneously different methods (direct processes measurements, nutrients and carbon budget calculations) at various time scales (from daily to annual) in the following sites: the Randers Fjord (Denmark), the Scheldt estuary (Belgium, the Netherlands), the Scheldt plume and the Bay of Palma (Spain). These sites have been selected because they offer a wide range of trophic status, from the 4

heterothophic Scheldt to the autotrophic seagrass bed in Palma. A second aim is to study the effect of nutrient speciation and organic carbon fractionation in these systems, which are characterised by various eutrophication levels. A third aim is to translate the results obtained into management criteria and protocols to improve monitoring procedures to assess the trophic status of coastal ecosystems.

1.3.- Aim and objectives. The purpose of this report is to determine, identify and quantify the different sources of nutrients that flow into Bay of Palma, relate them to qualitative impacts found in the area, estimate the ecological status of the Bay and its change over time as well as to assess initiatives around the Bay to reduce these inputs if necessary. To meet these goals, the following objectives are adopted:



To collect biotic and abiotic information of the Bay of Palma: climate (including rainfall pattern), sea dynamics, seabed ecosystem, waterbody parameters (nutrients, primary production, zooplankton, oxygen concentrations, water temperature, turbidity, salinity, etc)



To estimate existing loadings into Bay of Palma: whenever data are available, to use measurements of discharge (the flow) and nutrient concentrations to estimate the load contributed by surface water and groundwater.



To determine relationship between loadings and impact to the waterbody of the Bay: responses of the water body to variations in nutrient loading including changes in nutrient concentration, algal biomass and turbidity levels and other measurable changes.



To seek for factors, that can be managed, that can increase the effects of nutrient loadings: for this task other manmade impacts in the study area will be assessed.



To discuss the ecological status of the Bay of Palma: to compare symptoms observed and expected for eutrophicated areas



To analyse the repercussion of implementing the European Directives in the study area: with regard to the application of the Directives and their implementation as well as national or regional legislation

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To analyse the management of the area and to compare this with related values in the Mediterranean context (UNESCO, 1988).

1.4.- Sources of information. The information presented in this work was collected during the summer of 2002 in Mallorca, visiting the official and non-official organisations in Mallorca Island, from non governmental organisations to science institutes, as IEO (Oceanographic Spanish Institute) or IMEDEA (Mediterranean Institute of Advanced Studies), and through the island and local administration. Information about the Bay of Palma is found published in grey literature or in books collecting workshops articles. Spanish, and often Catalan, the regional language, are the languages employed in most of these papers. One of the goals met by this work has been to collect a great part of these diffuse publications, this work then could serve as a source of bibliography for future researchers in Bay of Palma. Sampling stations sited in the Bay of Palma differ in most of the papers and campaigns, because of their different objectives or sampling campaign designs. An improvement in this area would be to include former sampling stations sites in the design of new campaigns, which would make comparisons in time easier.

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Chapter 2.- Study area background: the Bay of Palma. 2.1.- The Mediterranean Sea. The Mediterranean Sea is unique, being a semi-enclosed Sea, with a narrow connection with the Atlantic Ocean through the Strait of Gibraltar (Figure 2), the manmade connection to the Red Sea via the Suez Canal and the narrow Bosporus Strait connecting it with the smaller enclosed Black Sea. The strait of Gibraltar controls the exchange of Atlantic and Mediterranean waters, and thus has an important role to play in the circulation and productivity of the Mediterranean Sea. The Sea contains some of the most extreme oligotrophic waters in the world (Dugdale & Wilkerson, 1998 in Turley 1999). Warm surface Atlantic water, already devoid of much of its nutrients by phytoplankton growth in the surface of the Atlantic, flows through the narrow Strait of Gibraltar and returns some 80-100 years later, having circulated the Mediterranean basin in an anticlockwise direction.

Figure 2.- Mediterranean bathymetry and location of the Balearic Islands in the Mediterranean context. (Source: modified from http://www.ssc.erc.msstate.edu). During its passage eastward, its nutrients decrease by phytoplankton assimilation (Bethoux et al, in Turley 1999); while climatic factors such as evaporation have resulted in its salinity increasing by up to 10 % (Milliman et al, 1992 in Turley 1999) The water flowing out of the Mediterranean, the Mediterranean Deep Water (MDW) is therefore 7

denser and flows below the incoming lighter Atlantic water. Because there is a west-east gradient in nutrients such as nitrogen and phosphorus (Krom et al, 1991 in Turley, 1999) there is a west-east gradient in productivity. The Mediterranean is a highly populated and the greatest tourist destination in the world, both of which are predicted by UNEP to rise substantially in the future. However, it includes some of the most extreme oligrotrophic waters in the world such that it is only capable of supplying 50% of its requirements for fish (Turley, 1999). The relatively clear, pigment poor surface waters of the Mediterranean have a general increasing oligotrophy eastward with substantially lower phytoplankton, benthic and fish production in the eastern basin. The Mediterranean Sea is highly sensitive to climatic changes; it has high evaporation rates, low land runoff from few rivers and seasonal rains resulting in a deficit in its hydrological balance. This has worsened with the damming of many rivers. Nutrient depleted Atlantic water flows into the Mediterranean through the narrow Strait of Gibraltar and exits after circulating the basin with nearly 10 % more salt content. Nutrients are a major controlling factor in oceanic productivity and often influence the type and succession of phytoplankton. Changes in river flow and agricultural practice can influence the concentration and ratio of different nutrients flowing into the sea. The predicted population increases especially along the southern shores, seems likely to result in eutrophication and an increased risk of pollution in other areas unless well managed (Turley, 1999).

2.2.-Nutrients in the Mediterranean. The nutrient concentrations encountered in the Mediterranean waters- nitrate, phosphate and silicate- are controlled by the exchanges at the straits of Gibraltar and Sicily, by atmospheric inputs and by fluvial discharges. In contrast with nitrogen, the phosphorus present in the Mediterranean waters is primarily discharged form land based sources. The UNEP report (1988), quoted in Karafistan et al (2002), states that terrestrial phosphate input into the Mediterranean Sea has been increasing considerably since 1960. UNESCO (1988) considers that in general, phosphorus concentrations in Mediterranean surface waters can be classified as background levels being at extremely low 0.03 μmol P/l or less; eutrophic coastal waters with values higher than 0.15 μmol P/l and highly eutrophied systems, well beyond 0.30 μmol P/l.

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Nitrogen, in the form of inorganic compounds, is quite deplete in the surface waters of the Mediterranean Sea although not to the same extent as are phosphates (UNESCO, 1988). Generally, background concentrations are about 0.1 μmol/l of N-NO3, 0.5 of N-NH4 and 0.1 of N-NO2; in eutrophic waters concentrations are equal of greater than 0.2 μmol/l of N-NO3, 1.0 of N-NH4 and 0.2 of N-NO2. In heavily eutrophied coastal waters guide values (UNESCO, 1988) are equal or greater than 0.5 μmol/l of N-NO3, 2.5 of N-NH4 and 0.5 of N-NO2. Considering the generally oligotrophic nature of the Mediterranean Sea, the decisive role of phosphorus as a limiting factor of pelagic productivity appears widely accepted: the N:P ratio is significantly higher than the assimilatory optimal (N:P=15:1)(Redfield ratio), usually above 19:1. However there are indications of bimodal limitations, being nitrogen limiting at least during winter (UNESCO, 1988).

2.3.- The Balearic Islands. The Balearic Islands are located in the Western Mediterranean (Figure 2) approximately 200 km east of the Iberian Peninsula. The three largest islands of the set are Mallorca, Minorca and Ibiza (Figure 3), and are separated from the Iberian Peninsula by the Balearic (or Catalan) Sea (Werner et al, 1993).

Figure 3.- Islands of the Balearic archipelago and location of Bay of Palma in the islands context. (Source: Modified from Servei Hidraulic, 1987)

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Mallorca is the largest of the set with a surface of 3624 km2 and a perimeter of 16540 Km. The island has three main embayments, two on the north: Pollença and Alcudia and one in the south, Bay of Palma (Figure 4).

Figure 4.- Location of the bays in Mallorca geography. (Source: Modified from http://www.platerritorial.com)

2.4.- The Bay of Palma. The Bay of Palma , the area of study, is located in the southern coast of Mallorca and can be regarded as limited by the Cala Figuera cape (39o 27,52’ N/ 2o 31,50’ E) on the West and Blanco Cape (39o 21,47’ N/ 2o 47,38’ E) on the East. Its mouth is of 14.7 miles and penetrates landward around 8.2 miles. Its surface and volume are approximately of 254 Km2 and 6.661·106 m3, respectively. Bay beds within the Bay have a shallow slope reaching 50 m depth only in the Western half of the Bay’s mouth (Gómez et al, 1986) The Bay of Palma is a semi enclosed area forced principally by the generally small coastal wind regime which produces a poor turnover ratio, especially in summertime (Gómez et al, 1986). Additionally, no notable river discharges into the Bay, being principally the entrance of pollutants and nutrients from outfalls and storm-water run-off (hereafter referred as torrents).

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Chapter 3.- Abiotic and ecological features of Bay of Palma. The Bay of Palma can be considered as an insular neritic area open to an oligotrophic sea (central area of the western Mediterranean), under the influence of a very intense navigation pressure and a high population density along almost the whole of its coast (Jansá, 1994). In some sections results of May 1991 have stood out because of their possible relation with torrent discharges, this is discussed later on (later section).

3.1.- Hydrographical Study. A hydrographical study of this area includes the dynamics of the Mediterranean water masses and their circulation. Modified Atlantic Waters (MAW) are found in the surface, lying over the Levantine Intermediate Waters (LIW) and next to the seabed the Western Mediterranean Deep Waters (DW). In addition, Western Mediterranean Intermediate Waters (WIW) can be found occasionally, which circulates between the MAW and LIW masses. Focusing on a shallow area as the Bay, only the shallower water circulation will be considered. The circulation could be summarised as; the Atlantic Water cross the Gibraltar Strait and runs along the African Coast producing clockwise eddies and affecting the southern part of the archipelago, even crossing the islands’ channels being its circulation constrained by the presence of a front between the Balearic Islands and Alger, known as the Balearic front. The presence of these waters is stronger during spring and summer and is not generally more than 38 psu (López Jurado, 1990). The kind of water that would be introduced by the sea breeze inside of the bay should have the same features as this water mass. The breeze is assumed to be mainly responsible for the movement within the Bay because of its reduced depth and the small effect of the freshwater discharges. The sea breeze normally blows from the SW; meanwhile storms are mainly form the WSW or NE and occur principally in winter. Calm conditions (0.5

During 1988-1992 high concentrations of nitrites were found in medium and high depths, meanwhile high surface concentrations are not so common. Annually, the concentration increases from the end of summer reaching its maximum in the transition between autumn and winter, or during the winter season. Spatially, the average concentrations for the column decrease with a progression offshore of the bay coast, with values comprised between the minimum 0.03 and maximum 0.50 μmol N/l. During the study period, water column average nitrite values were uniform for the port areas, always higher than the rest of the Bay, while their values decreased for the offshore areas. However, during the period 1980-1983 the averaged water column values ranged between 0.00-0.60 μmol N/l, with occasionally medium and high depths high concentrations (Jansá et al, 1994). The values range is similar to the one 17

found in the outer area of the Bay by Fernández de Puelles (1997) in 1993-1994, which were 0.02-0.55 μmol N/l. The EUBAL 1 sampling campaign in the Bay of Palma found an average value for nitrite concentrations of 0.04 ± 0.01 μmol N/l, being the range of concentrations between 0.00-0.13 μmol N/l (unpublished data). These concentrations are very low for the area, compared with former studies, and lower than the reference station. The more recent values (May-September 2001), measured by the Department of Health in the shoreline waters (unpublished data) found average concentrations of 0.34 ± 0.06 μmol N/l, with values ranging from 0.05-1.58 μmol N/l. According to UNESCO (1988) classification, such shoreline waters would be between eutrophic and heavily eutrophied waters due to its high nitrite concentrations.

3.6.2.- Nitrates.

UNESCO (1988) classified nitrate concentrations for the Mediterranean, in terms of eutrophication, with the following concentrations:

Nitrates ( μmol N/l)

Background levels

Eutrophic waters

Heavily eutrophied

0.1

0.2

>0.5

The Nitrate behaviour follows the same pattern as nitrites with maxima around 1.52.0 μmol N/l, sometimes higher in ports areas (3.0 μmol N/l). Higher values can appear in surface measurements with no correspondence to the nitrites pattern, which may be the result of exterior inputs and a latter transport to the centre of the Bay. In May 1991 concentrations around 5 μmol N/l appeared at 20 m depth in the centre of the Bay (Jansá et al, 1994). Small scale fluctuations could be due to functional origin or molecular diffusion and current transport phenomena. The shallowness of the bay prevents the detection of mineralisation processes, although this does not mean that they are absent. Spatially, higher values can be found in the port area, then near the shore, than in the rest of the bay with values for the water column between 0.6-1.5 μmol N/l in the port area and values for the rest of the bay between 0.1-0.5 μmol N/l. An increasing trend in data

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was observed in the period of study consulted (1988-1992) for the whole bay water mass (Jansá et al, 1994). Chacártegui (1980) found, in a similar study carried out between the summer of 1978 and the summer of 1979, that nitrate values within the Bay ranged between 0.03-0.5 μmol N/l., with maximum values found in 1978 winter and 1979 summer. These values are similar to those obtained by Jansá et al (1994) for the Bay apart from the surroundings of the port. In fact, there are no reference values higher than 0.5 whereas ten years later maxima were found around 1.5-2.0 μmol N/l. Similarly no such high values were found during campaigns carried out between 1980-1984 (unpublished and untreated data provided by Chacártegui) where the absolute maximum was 1.25 μmol N/l in the mouth of an outfall. Thus, an increasing trend of nitrate concentration can be observed in terms of maximum concentrations found. Generally, nitrate concentrations in the reference station were low with an average value of 0.67 μmol N/l and a range between 0.00 and 4.83 μmol N/l. High values corresponded to depth waters in autumn and winter time (Fernández de Puelles, 1997). The EUBAL 1 sampling campaign values for nitrite concentrations (unpublished data, EUROTROPH webpage) were similar to the range found in former studies, as found with nitrites, ranging between 0-0.56 μmol N/l and a mean level of concentration of 0.21 ± 0.03 μmol N/l. Whith respect to shoreline waters, extremely high values were found at the Playa de Son Matias, by the Health Department (unpublished data), with maximum concentrations between 25-70 μmol N/l during June-July 2001. The average value for nitrates in this beach was in the period May-September 2001 of 28.51 ± 8.31 μmol N/l. The descriptive data for the rest of the shoreline, excluding Son Matias, results obtained were very high as well, with an average of 3.68 ± 1.11 μmol N/l in a range of values between 0.25-2.71 μmol N/l, it is of note that the high results found in front of the emergency outfall of Palma II (Baluarte) and near the Palma II UWWTP regular outfall (Ciudad Jardín). The contents of these shoreline waters can be classified using the available data as heavily eutrophied waters.

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3.6.3.- Phosphates. Phosphates levels are classified in terms of eutrophication in the Mediterranean, according to UNESCO (1988) with the following concentrations:

Phosphates (μmol P/l)

Background levels

Eutrophic waters

Heavily eutrophied

0.03

0.15

>0.30

Chacártegui (1980) found phosphates concentration ranging between 0.00-0.07 μmol P/l, being the maximum during 1979 summer and the minimum in 1978 summer. In 1980 values were similar to this interval ranging 0.00-0.15 in the centre of the Bay, except for a station located near the Baluarte outfall with maximum surface value of 2.5 μmol P/l and in Palma port mouth of 1.09 μmol P/l during May. During 1981 and 1982 water concentration in phosphorus apparently increased ranging 0.00-0.20 μmol P/l in the centre of the Bay. During 1988-1992 average column values for phosphates ranged 0.03-0.35 μmol P/l. Jansá et al (1994) concluded that the rapid use of this substance by the phytoplankton, and its tendency to precipitate made difficult the interpretation of its temporal variation during their study period. Although their maximum distribution sometimes coincided with the ones found for nitrites and nitrates, the lack of correspondence with the silicate maximum in some cases, made Jansá et al (1994) conclude that not every time this maximum corresponded with external inputs. Sometimes it could be due to a rapid physical input (as resuspension, diffusion or accumulation by transport) or the results of functional processes (as recycling or fast use by phytoplankton). Jansá et al (1994) found no clear spatial distribution of phosphates; there was no decrease with distance from the shore as was shown for nitrites and nitrates. During the study period (1988-1992) there was a decrease of the values of phosphates with time. At the reference station, phosphorus concentration was low with an average value of 0.12 μmol P/l and a range of 0.03-0.31 μmol P/l, being practically undetectable in the surface during summer (Férnandes-Puelles et al, 1997) The Health Department found for the period May-September 2001 phosphate concentrations ranging 0.05-2.15 μmol P/l with a correspondent average of 0.21 ± 0.07 20

μmol P/l (unpublished data), and a maxima in the waters analysed in front of the Baluarte outfall. Health Department data are especially important because they were taken during summer time when there are assumed to be low concentrations of phosphorus. According to the UNESCO guide values for phosphates concentrations, waters with this concentration of phosphates would be included between eutrophic waters and heavily eutrophied.

3.6.4- Silicates. The first reference found for silicates concentration in Bay of Palma waters is during 1982-1983 (Chacártegui G. unpublished data) where values ranged from 0.02-0.90 μmol Si/l but with higher values for the station located in the Baluarte outfall, where a maximum value of 3.71 μmol Si/l appeared in May 1983. Silicate values, during the period 1988-1992, ranged from 0.0045 to 1.9 μmol Si/l, but higher maxima were found in the centre of the bay during 1991 with concentrations of 4 and 8 μmol Si/l. Jansá et al (1994) found the temporal variation between silicates and nitrates similar and assumed these high concentrations to external inputs, probably land inputs. In May 1991 concentrations of 5 μmol Si/l appeared at 20 m. depth in the centre of the Bay. Spatially, average column values were higher for the port area respect the rest of the bay. An increasing trend with time can be appreciated during this study period (Jansá, 1994). There are no UNESCO recommendations for silicate background concentrations, but regarding data from the reference station concentrations should be below 0.6 μmol Si/l. which is the minimum value found in summer time. Concentrations at the reference station ranged, during 1993-1994, 0.56-3.27 μmol Si/l with an annual average of 1.01 μmol Si/l (Fernández de Puelles et al, 1997). Data found in the EUBAL 1 campaign (unpublished data, EUROTROPH webpage) show values ranging 0.65-1.92 μmol Si/l, with an average value of 0.98 ± 0.01 μmol Si/l which are similar to the reference station, and a maximum of 1.62 μmol Si/l. The Health Department did not analyse Silicon concentration in coastal waters.

21

3.6.5. Nutrient conclusion. Jansá et al (1994) concluded in their study that the main water of the Bay of Palma was oligotrophic giving rise to very fast planktonic processes. In addition, their study concluded that because of the hydrodynamics of the Bay only inshore eutrophication during part of the year could be seen. The short duration of the thermocline in the Bay followed by an homoeothermic water column, leading to vertical mixing of the water column, explain the lack of clear patterns in the temporal variation of parameters as nutrients, Chlorophyll a and zooplankton biomass. It is of note that, the so-called reference station includes into its range of values those of deep waters, which are nutrient-rich. This makes valid comparisons and conclusions more difficult. However, a depth data separation should be done for further analysis. Although campaigns have different durations and purposes, some conclusions can be obtained from their temporal variation. The nitrite range of concentrations (Table 1, figure 9) is relatively constant during time, except in shore waters where the maximum is very high compared with the other campaigns. In addition, the range includes all the type of waters that UNESCO (1988) defined. Hence further analysis is necessary to determine in which type is located the gross of the measurements and their spatial distribution, although shoreline waters have higher concentration than the rest of campaigns indicating the grade of hypernutrification. Nitrates (figure 10), phosphates (figure 11) and silicates (figure 12) show a tendency to increase their range during time, as well as showing higher values in coastal waters (05/2001-09/2001), thus indicating an anthropogenic influence in their concentrations. Further analysis in the percentage of cases located in each water type of UNESCO (1988) should be done for defining the nutrient situation. Coastal waters could be regarded as hypernutrified by human influence (figures 9, 10, 11 and 12) but their maximum value of the range is almost always far below that for the heavily eutrophied waters referred to in UNESCO (1988). UNESCO (1988) values where set during a scientific workshop convened by the UNESCO, UNEP, FAO and Regione EMilia Romagna (Italy)on eutrophication in the Mediterranean Sea convened by the UNESCO, UNEP, FAO and Regione EMilia

22

Romagna (Italy). As a result of the scientific papers presented at the meeting the guidelines for monitoring, assessment and control of eutrophication in the Mediterranean Sea were adopted. 1.8

1.6

Nitrite Concentration (micromol N/l)

1.4

1.2

1 nitrite minimum concentration nitrite maximum concentration 0.8 UNESCO (1988) reference values ____ Heavily eutriphied ------- Eutrophic waters ……. Background level

0.6

0.4

0.2

0 campaign 1980-1983

campaign 1988-1992

campaign 04/199304/1994 reference station

campaign EUBAL1 1998

campaign 05/200109/2001

Figure 9.- Nitrite range of concentrations in the different campaigns.

6

Nitrate Concentration (micromol N/l)

5

4

nitrate minimum concentration nitrate maximum concentration

3

UNESCO (1988) reference values ____ Heavily eutriphied ------- Eutrophic waters ……. Background level

2

1

0 campaign 19781979

campaign 19801983

campaign 19881992

campaign 04/1993-04/1994 reference station

campaign EUBAL1 1998

campaign 05/2001-09/2001

Figure 10.- Nitrate range of concentrations in the different campaigns.

23

2.5

Phosphate concentration (micromol P/l)

2

1.5 phosphate minimum concentration phosphate maximum concentration 1

UNESCO (1988) reference values ____ Heavily eutriphied ------- Eutrophic waters ……. Background level

0.5

0 campaign 19781979

campaign 19801983

campaign 1988campaign 1992 04/1993-04/1994 reference station

campaign EUBAL1 1998

campaign 05/2001-09/2001

Figure 11.- Phosphate range of concentrations in the different campaigns.

3.5

Silicate Concentration (micromol Si/l)

3

2.5

2 silicate minimum concentration silicate maximum concentration 1.5 reference value ………

Background level

1

0.5

0 campaign 1980-1983 campaign 1988-1992

campaign 04/199304/1994 reference station

campaign EUBAL1 1998

Figure 12.- Silicate range of concentrations in the different campaigns.

24

Table 1.- Minimum and maximum nutrient values found in the different campaigns Phosphate Nitrite Campaign

min

μmol N/l max

Nitrate

μmol N/l

μmol

Silicate

P/l

μmol

Si/l

min

max

min

max

0.03

0.5

0

0.07

Min

max

Campaign 1978-1979 Campaign 1980-1983

0

0.6

0

1.25

0

0.15

0.02

0.9

0.03

0.5

0.1

2

0.03

0.35

0.045

1.9

0.02

0.55

0

4.83

0.03

0.31

0.56

3.27

0.04

0.13

0

0.56

0

0.56

0.65

1.92

0.05

1.58

0.25

2.71

0.05

2.15

Campaign 1988-1992 Campaign 04/199304/1994 Campaign EUBAL1 1998 Campaign 05/200109/2001

3.7.- Oxygen saturation. This parameter defines globally the status of the system due to its high stability with respect to other parameters (Jansá et al, 1994). During 1982 oxygen saturation percentages ranged from 95% to 130%, with July surface maxima of 122% in the mouth of the Bendinat outfall. Jansá et al (1994) pointed out that the value of oxygen saturation was never less than 4 ml/l during the study period (1988-1992), including areas within the port. They also considered during this study that the system was far from eutrophication, even in port areas. Seasonally, the values of oxygen saturation fluctuate between 85 % and 135 %, with maximum during spring and decaying in autumn. Of special interest for the purposes of this study are high percentages (>130%) in the surface in May 1991 in the centre of the bay and within the port. The average values for the whole column tend to decrease within

25

the port (110% in 1988 and 102% in 1991) with time, while tending to be maintained in the rest of the stations of the bay. Spatially, at the beginning of the period, oxygen saturation was higher within the port than the rest but by the end of the study period it was the lowest of the stations (Jansá et al, 1994).

3.8.- Chlorophyll a. Jansá and Carbonell (1988) conclude that chlorophyll a concentrations within Bay of Palma in 1982 had a similar range to those found elsewhere in of the Balearic Sea. However, values found near the shore could be due to urban influence, which is especially noted in summer time, when lower values should be found because of the absence of river inputs and a decrease in the vertical exchange of water masses. Values during this year ranged from 0.1 to 1.5 mg m-3, with the higher values in the innermost part of the Bay. The eutrophy, very biologically productive due to relatively high rates of nutrient input, and the absence of high quantities of solids in suspension were cited by to Jansá et al (1994) to explain the vertical distribution of Chl a. These distributions consist of an increase in the maxima as the warm season approaches and the observation of a superficial maximum characteristic of eutrophicated areas. The maxima in coastal stations located within bay, appeared in the transition between winter and spring, with values around 3 mg m-3. The summer desertification, absence of phytoplankton occurs due to stratification and lack of mixing with rich nutrient waters, could be observed as well, but not as sharp as in the open sea, presenting values smaller than 0.2-0.3 mg m-3. Values within Palma port were always higher than the rest of the bay, with annual maxima of 4 mg m-3 (July 1991), which indicate that the port area regime has a tendency to eutrophication. Autumn maxima were less clear due to the secondary proliferations or accumulations typical of neritic zones close to the shore, especially if they are subject to anthropogenic pressure. All the Bay maximum values during this period appear to have increased with respect the values in 1982, where even in port areas the maximum found was 1.5 mg m-3. This suggests an increasing tendency in Chl a concentrations for the whole bay (Figure 13). Over time there was a tendency of the average values for the whole column was to decrease in Chl a for the port area and stability for the rest, with a small decrease for the innermost areas and an increase in the centre of the bay. With respect to the reference

26

station, Chl a ranged from 1.11 mg m-3 in January 1994 to 0.07 mg m-3 in August 1993, with an average of 0.27 mg m-3 In May 1991 there was a maxima of Chl a within the port 4.94 mg m-3 in the innermost (Jansá J. unpublished data) and 2.71 mg m-3 in the outermost, and in the centre of the Bay with 2.27 mg m-3, while a station located in the west part presented a value for Chl a of 0.87 mg m-3.

4.5

4

Chl a Concentration (mg m-3)

3.5

3

2.5 Chl a minimum concentration Chl a maximum concentration 2

1.5

1

0.5

0 campaign 1982

campaign 1988-1992

campaign 04/1993-04/1994 reference station

Figure 13. Chl a concentrations in the different campaigns and in the reference station.

Although Chlorophyll a range of concentrations is bigger within the Bay than the reference station, this comparison should be taken carefully because of the different processes taking place in both areas. And especially when data taken from restricted circulation as a port and an open sea area are compared.

3.9.- Zooplankton. In the year 1982, the lowest zooplankton biomass appeared in November and the highest in September. During September some correspondence was noted between Chl a

27

and zooplankton biomass distribution, because of the big quantity of both (Jansá and Carbonell 1988), with values higher than 40 mg m-3 using a 250 μm mesh.

The average biomass (as dry weight) measurement decreased with distance from the shore, in the study period (1988-1992) of Jansá et al (1994), being 7.40 ± 2.08 within the port, 7.30 ± 1.34 in a coastal area and 6 ± 0.9 mg m-3 in the centre of the bay for the fraction over 250 μm. These values are much higher than the values obtained for the surrounding area of the Balearic islands in a campaign during 1985-1988, where the average for neritic samples were 3.79 mg m-3 (Fernández de Puelles M. L., 1990), but much smaller than the 1982 survey. However a campaign between 1993-1994 in a neritic station outside the bay found values similar to the port ones, with an annual average for a 250 μg mesh of 7.34 mg m-3 dry weight (Fernández de Puelles et al, 1997). Studying the same areas but with a mesh size of 100 μm the results were 32.4, 21.8 and 14 mg m -3 respectively. Jansá et al (1994) found, using the 100 μm mesh, that the biomass content was more abundant during springtime, which can be seen for the station in the centre of the bay. An important increase occurred during summertime in the coastal and port areas due to eutrophication. On a temporal basis, the fraction greater than 100 μm tended to decrease meanwhile that captured with the 250 μm mesh were increasing during the period studied. With respect to its composition, zooplankton is dominated by copepods (>60 % in abundance) with the presence of apendicularians, jellyfishes and cladoceran (Jansa, 1985 and 1988). Jansá et al (1994) concluded that the presence of summer peaks of zooplankton biomass, when low biomass should be found, in the port area and coastal area indicate the eutrophication conditions of coastal areas.

3.10.- Marine vegetation. In the Bay of Palma, two different areas can be differentiated in relation with vegetation cover, limited by depth. The innermost area, as well as the areas closest to the shore, and with less than 30 m depth, is occupied by Posidonia oceanica meadows, generally mixed with Caulerpa prolifera. Between 30 and 50 m depth, maërl beds can be found, composed almost of Phymatolithon calcareum with practically no epiflora (Gómez, Ribera and Chacártegui, 1986)

28

3.10.1.- Posidonia oceanica: Ecosystem role. Due to the influence on the regulation of the Bay of Palma ecosystem it is necessary to describe the features that make the presence of these meadows so important to the coast.

3.10.1.1.- Basic Features of Posidonia oceanica meadows.

Posidonia oceanica is a slow-growing long living, up to 4000 years, submerged marine flowering plant (not an alga), which forms vast underwater beds or meadows, housing and feeding very large numbers of other species (EEA, 2002). This species is one of the most characteristic and relevant of the Balearic Island coast; with around 750 km2 it is one of the ecosystems most widely distributed in the archipelago. Its presence triple the biological production of organic matter in the Mediterranean coast, being then an essential form of organic matter for the marine trophic system (Massutí et al, 2000). Its rhizomes grow horizontally and vertically creating a three-dimension structure. Until the sediment surface has not been occupied the growth, is principally in the horizontal plain by 5-6 cm/year, then the most of the rhizomes tend to grow vertically at a rate between 0.5 and 3 cm/year, depending on the annual quantity of accumulated sediment (Massutí et al, 2000). The rhizome net, as well as the leaves, trap and stabilise bed sediments, avoiding sand resuspension and slowing water currents, thus increasing sedimentation of particles burden by the current and protecting the shoreline of coastal erosion. The Posidonia meadow creates a shallow barrier between the coast and the external dynamics. Eventually the leaves of the meadow can reach the surface. This not very common today as since ancient times man has destroyed them for being an obstacle for navigation. In addition, the presence of the meadows provide sand deposition at the Bay of Palma coast, not having a major contributor of sediments as rivers, due to the erosion of rest of calcareous shells of the organisms living within the meadow (Massuti et al, 2000 and Mateu G. pers. comm.). Thus, Posidonia oceanica meadows play a key role in stabilising the coast shoreline.

3.10.1.2.- Organisms related to Posidonia oceanica.

In terms of biodiversity, these meadows present a species richness higher than the rest of Mediterranean benthonic communities, much higher than in unvegetated sand beds 29

(Massutí et al, 2000). This s in part explained by the diversity in microhabitats. Two large groups of habitats can be identified: those associated with the leaves and the rhizomes. The first is characterised by a higher light availability and less physical stability than the rhizomes environment. These circumstances provoke differences between the kinds of sessile organisms present in both habitats. Also, in the meadow live organisms that are not linked to any of these two habitats. Leaves, because of the particularities of this habitat in continuous movement, are colonised by very specialised organisms, with short living periods because of the continuous growing and falling of the leaves. The organisms comprise epiphitic species seeking for light and filter-feeders organisms (Massutí et al, 2000). The rhizomes community varies depending on the density of the meadow. In addition, other organisms are related to the meadow for trophic relationship, the echinoderm Paracentrotus lividus is the biggest Posidonia consumer; this species can control the Posidonia meadow evolution. The meadow plays another important role for fish populations, because it offers nursery and breeding area (Massutí et al, 2000)

3.10.1.3.- Fate of Posidonia oceanica production.

As indicated above, the Posidonia meadow is a highly productive ecosystem, but only a small proportion, 2-10 % (Cebrián et al, 1996 and Pergent et al, 1997 in Massutí et al, 2000) is consumed by herbivores, which, in addition, have a low assimilative efficiency because of the difficult digestion of the plant components. Faecal analysis of the meadow consumers show that their preference is for the epiphytes instead of the plant itself, which provokes the entry of matter into the bacterial food chain. Posidonia fragments are poor in nutrients so bacteria need to incorporate nutrients resulting and adequate material for scavengers to degrade it. This is a very slow process (Massutí et al, 2000). A high proportion, around a 30%, of the Posidonia meadow production is buried in the sediment. Although most part is degraded in the sediment (Cebrián, 1997 in Massutí 2000), more than 5% remains buried in the sediment. Thus, regarding the extension of the Posidonia meadows, they work as a sink of CO2 and nutrients, thus giving Posidonia meadows a role as a sink for excess materials in coastal waters. Also, because the meadow is an open system with a constant organic material, and nutrients, losses, an external nutrients inputs is necessary (between the 21-45 % of the annual requirements (Mateu and 30

Romero, 1997 in Massutí 2000) for grow supporting. This is the reason why Posidonia can absorb nutrients through leaves and roots (Massutí et al, 2000). This last point is especially important for the purposes of this report.

3.10.1.4.- Functional role of Posidonia meadows.

Among the multiple functional roles offered by Posidonia meadows, some are especially important for the purposes of this report (Massutí et al, 2000): 

Oxygen production: Considering that Posidonia oceanica meadow produce vegetal biomass that is not degraded, and then does not consume oxygen, the meadow can be consider as a net oxygen producer (i.e. 14 l O2 m-2d-1 in Corsica at 10 m depth). Part of this oxygen production is transported to the roots then oxygenating the sediment, avoiding the soil deoxygenation.



Nutrient sink



CO2 absorption



Fixation and protection to multiple organisms



Coastal erosion mitigation



Sediment production

3.11.- Land Hydrogeology. Almost all waters that flow into the Bay of Palma are collected from the hydrogeological unit of Palma plains (Llanos de Palma) (figure 14). This unit is located in the western extreme of the so-called Central Plains of the island (subsiding complex bowls filled up with Tertiary and Quaternary materials (Servei Hidraulic, 1987)), they occupy a total surface of 370 km2, being 350 km2 of permeably upwellings. These plains are limited in the Northwest by the Tramuntana mountain range, in the North by Inca-Sa Pobla Plains, in the East by the Central mountain ranges and by the South and Southeast by the sea and Llucmajor platform (ITGE and JAB, 1997).

31

Figure 14.- Palma plains hydrogeological unit limits (Source: modified from the Spanish Geological and Mining Institute web page http://www.igme.es)

32

Chapter 4.- Human uses of the area. 4.1.- Residence and tourism. By the end of the 1960’s, the term “balearisation” was defined as a synonym for intensive and anarchy urbanisation in the shoreline (Gual, 2001). Residence and tourism practically occupies almost the whole of the land around the Bay of Palma as can be observed in figure 15. The large scale urban development around the Bay, is explained by previous time economic and political situations. Blàzquez et al (2002, from Rullan 1998 and 1989) in their book, divide the population growth into three large tourism and building phases (“booms”):

Urban Land Earmarked for urban development with approved urban plan Earmarked for urban development without approved urban plan Reclassified as rural land Pending of classification

Figure 15.- Land uses around the Bay of Palma (Source: Modified from www. platerritorial.com) 

First boom: It coincided with the tourism boom of the 1960’s and the integration of Spain in the world economic order. This first period is characterised by an intensive building of the shoreline, especially concentrated in the Bay of Palma;

33



Second boom: Until the beginning of the 1990’s, coinciding with the crisis of the Gulf War, this period was characterized by a building extension, not so sharp as the former period;



Third boom: Coinciding with an expansion of the global economy since 1993 although some conservation designations have arisen, the human and building pressure and their indicators has grown, especially around the coast.

The Bay of Palma shoreline belongs to three different municipalities from West to East, Calvià, Palma and Llucmajor. The city of Palma de Mallorca has the biggest agglomeration. The residence population of the Bay of Palma was in 1996 around 350 000 and the seasonal maximum population, including the residence population, was around 450000 (data taken from JAB 1998). This represents around the 35% of permanent population of the island and 45% of total population during peak time. In 2001 resident population of Palma city was around 360000 (Palma Municipality unpublished data), and had increased very rapidly since 1950 when the residence population was around 135000. Figure 16 clearly identifies the three different periods mentioned above. With respect to the bay, in 2001 the official resident population was around 400000 (data provided by Calvià, Llucmajor and Palma municipalities) and maximum tourist places where for 85182 persons (data provided by CITTIB). However this is less than in 1996, since when it has increased in more than 3% for the whole island (Blàzquez et al, 2002), and although this could be due to different methods used for the estimation. The above data indicate that maximum population of the bay was approximately 500000 persons in 2001. 400000 350000

Residence population

300000 250000 200000 150000 100000 50000 0 1950

1955

1960

1965

1970

1975

1981

1986

1991

1996

2000

2001

Year

Figure 16.- Evolution of residence population in Palma Municipality. 34

Apart from land based tourism, boat-based tourism is a very important sector in tourism; around the bay there are 13 marinas or nautical ports (Plà Territorial de Mallorca 2002), which represent 31.7% of this kind of infrastructures in the island. Also in Palma is located a goods and passengers port. This point will be discussed broadly in section 5.2.3.

4.2.- Agriculture and farming. Traditionally, agricultural activities of the Palma Plains hydrogeological unit have been important, and is concentrated principally in the Plà of Sant Jordi (Centre-South of the unit). The intense extractions from the freshwater wells provoked the marine intrusion in the aquifer, consequently making it unsuitable for agriculture, thus many agricultural lands were abandon (ITGE and JAB 1997). In 1972, a project of the Agriculture Ministry with the aim of using of treated wastewater from the wastewater treatment plant (Palma I), made the area become of National Interest. Using treated wastewater for 225 ha (Palma I) and 1500 ha (Palma II), were used for growing cereals and vegetables. The total cultivated surface in the hydrogeological unit is approximately of 9.288 ha dominated by vegetables, cereals and fruits (ITGE and JAB 1997). Cattle raising activities in the Unit are located on 23 farms (1996), and principally cattle although birds (33.200) and pigs (1600) represent the largest livestock (ITGE and JAB 1997). Due to these previous aspects, two principal areas of nitrates contamination are located in the Unit centre (Plà de San Jordi), with values ranging between 50 and 100 mg/l NO-3, with a maximum of 174 mg/l. In the rest of the unit nitrate values ranges between 10 and 25 mg/l (ITGE and JAB, 1997). Nitrate content evolution, measured in wells present in the unit, was an increase from relative low levels (10-20 mg/l) in the whole of the plain except the Plà de San Jordi (3040 mg/l) in 1977 to 30-40 mg/l for the North of the unit, 70-80 in the Plà and to almost 50 mg/l for the rest of the unit. The evolution of the Plà de San Jordi was different than the rest of the unit; while the rest of the unit decrease in value to the actual concentrations of 10-20 mg/l, the Plà of San Jordi decreased its concentrations by the end of the eighties to 50-60 mg/l. Since 1994 it has maintained averaged values around 100 mg/l. These concentration values are high due to the join effect of using fertilisers and the reuse of wastewater (ITGE and JAB 1997) because of the decrease of extractions from wells and

35

the salt water intrusion that suffered the whole unit. This area was designated as a National Area of Interest for Sewage Water Irrigation (ITGE and JAB, 1997).

4.3.- Industry. Inputs from population agglomerations to bay coastal waters are almost urban effluents, as around the Bay of Palma most of the companies are providing services, with only small light industries involving leather, dairy products, beer and mechanical workshops companies. Thus the outfalls practically only emits urban treated sewage water (Gómez et al, 1986). Thus tourism, including boating activities, should be regard as the main industry in Mallorca. In fact, the 85 % of the income of the Baleric Islands is related, direct or indirectly, to tourism activities (Ecotourism tax official webpage)

36

Chapter 5. - Nutrient inputs on the Bay. 5.1.- Introduction. The Bay of Palma has diverse sources of nutrients, including diffuse sources as torrents, groundwater and atmosphere inputs and point source inputs as urban wastewater treatment plants (hereafter UWWTP), thermal stations, marinas, aquaculture installations and desalination plants. The diffuse sources to the bay include anthropogenic inputs, due to the use of fertilisers on agriculture, changes in the type vegetation and emissions to the atmosphere, their nutrients contents have increased. The sources of nutrients and organic matter for the coastal ecosystem can be classified into two groups: the point and nonpoint (or diffuse) sources. Point sources flow out at discrete, identifiable locations and their impacts can be measured directly (Rossi et al, 1992 in Arhonditsis et al, 2000). However, the largest nutrient contribution for coastal marine environments is from nonpoint sources, that are rather diffused and highly variable from year to year depending on climate and rainfall (Borum, 1996 in Arhonditsis et al, 2000). The most important nonpoint loads include the wet and dry deposition of land, the weathering of minerals and anthropogenic sources. The latter is related in the case of the Bay of Palma to activities such as boating activities, erosion of soil materials form agricultural farming, and increase in nutrients contents in groundwater.

5.2.- Point source inputs. The Bay of Palma point source inputs include the UWWTP, desalination plants, the thermal power station (and its aquaculture plant) and torrent discharges. Point source inputs can be divided in episodic inputs, i.e. not emitted on a regular basis, and discharges where the emissions are part of the process. In this class of inputs include marinas and boating places due to the exact location of their infrastructures unless some of their emissions are diffused as well. Around the bay there are 4 major UWWTP: Palma I, Palma II, S'Arenal and Bendinat. The first two (Palma I and Palma II) are located in Palma de Mallorca municipality and they are managed by EMAYA, a municipality company for public water and sewers. S'arenal one is located in Llucmajor municipality and Bendinat located in 37

Calvià plant is being managed by a public company called Calvià 2000. S'arenal plant stopped operating in year 2001, being replaced by a new one, which at present is been tested by the building company. The company will test it for a year before being it is transferred to the local management services. In addition, there are many private plants, with minor or seasonal outputs. Only private plants and Palma I do not emit in a regular basis, so they will be considered as episodic inputs.

5.2.1.- Episodic inputs. Episodic inputs in the context of the Bay of Palma include torrents, due to the absence of permanent rivers and the irregularity of rainfall, and some of the UWWTP, which discharges are only during emergencies.

5.2.1.1.- Torrent inputs.

Although there are no permanent rivers in the islands, there are superficial watercourses, torrents, that flow into the Bay of Palma. The environmental section of the Balearic Government has a network of flow meters for the Island torrents. There are many torrents (figure 17) flowing to the Bay, but there is only metering of two of the main torrents: Torrent Gros and Torrent Riera (figure 18). The stations closest to their respective mouths represent approximately the amount of water that reaches the coast, being their average flows 1.57 and 1.3 for Torrent Gros and Torrent Riera, respectively for the period 1976-2000 (average of years with the complete set of monthly data). Inputs to the sea are not regular flows, but they occur in violent rainfall episodes. The averages are not representative of the behaviour of these courses, due to the seasonality of the climate. In drought years torrents do not occur and in the higher rainfall periods the discharges reach annual maxima of approximately 10·106 and 7 ·106 m3 per year respectively. Because of the permeability of the area some water permeates the ground, being possible that the amount of water metered in station 1 is smaller than in station 3 (figure 18) (Data taken from JAB, 2000).

38

Figure

17.-

Watercourses

drainage

in

Bay

of

Palma

(Modified

from

www.platerritorial.com)

Figure 18.- Catchments area for Torrent Gros and Torrent Sa Riera and location of flow stations.(modified from JAB, 1994) 39

There are not analytical data, in terms of concentration of nutrients, of these natural outputs of water to the Bay of Palma. In addition, the amount of water discharged to the sea is only an estimate based on assumptions. Other torrents canalise into these two torrents to the metering station, so these volumes are not measured (as happen with metering station 2 in Torrent Riera). Even some Sewage Water Treatment Plants and Desalination Plants discharge their output waters into these torrent stream waters down.

5.2.1.2.- Urban Waste Treatment Plants.

5.2.1.2.1.- Palma I Urban Waste Water Treatment Plant (data provided by EMAYA, except where referenced)

At present a new Palma I UWWT plant is being built to replace the original one, which will be dismantled. The latter plant has been working since 1971 and is designed for treating a flow of 15,000 m3/d, except the primary separation, which is for 7500 m3/d, and the impulsion chamber for irrigation which is for around 30000 m3/d. This plant provides for primary physicochemical treatment physicochemical and a biological secondary treatment stage. The incoming flow changes because of the variable population, having during peak times a flow of 12500 m3/d and during low population of around 6,000 m3/d (data from JAB, 1998), with an average value of 9365 m3/d for the year 2001. The outflow water is used for irrigating, thus is pumped to a regulation lagoon for irrigation. The amount of water treated during the year 2001 was 3,418,207 m3. In 1995 this plant was connected to the Ciudad Jardín outfall (figure 19), where eventually can discharge but only in emergency cases as an overflow.

5.2.1.2.2- Other wastewater outfalls.

Within the bay there are approximately 22 outfalls, some of them are used by the afore-mentioned UWWTP, other of them are of private management, others are out of use, others unknown. Although the Shoreline General Direction (Dirección General del Litoral) of the Environmental Deparment of the Balearic Goverment has an inventory of these

40

outfalls, it is unknown whether some of them are still used. The following section will indicate those with available information (data from JAB, 1998).

5.2.1.2.2.1.- Urbanization Sun Club El Dorado (D046)

This private UWWTP is located in Llucmajor municipality and it only operates during the tourism season; since the construction of the new S'Arenal Water Treatment Plant, it is planned that these waters are to be pumped into the new station. The outfall is located at around 6 m depth, in a rocky area with low hydrodynamics covered by Posidonia oceanica (Gual, 2001). This plant is provided with a preliminary treatment, removing grits and fats as well as large objects. In addition, it provides a primary treatment with activated sludge. The incoming flow is of 213 m3/d during peak times and none in the rest, treating 26000 m3/year (data from JAB, 1998). The data taken are, 1-4 measurements per year, on the outfall by the Water Laboratory, depending of the Environmental Department, (1995-2000 data are in Table 2). Table 3 shows the efficiency of this plant, calculated using an analysis of the inflowing and effluent waters.

Table 2.- Parameters concentration of Urbanization Sun Club El Dorado Average

Maximum

Minimum

Ammonium

15.98 ± 15.60

46.18

0.46

Nitrate

20.04 ± 27.50

86.54

0.00

Nitrite

12.61 ± 20.34

52.23

0.03

Phosphate

11.34 ± 6.07

20.05

0.42

COD

238.00 ± 248.00

725.00

37.00

BOD5

52.00 ± 70.00

230.00

4.00

130 ± 148

500.00

15.00

Concentration (mg/l)

Total Suspended Solids

41

Table 3.- Efficiency of Urbanization Sun Club El Dorado UWWTP Parameter

Efficiency

COD

82 ± 19 %

BOD5

92 ± 11 %

Total Nitrogen

41 ± 38 %

Total Phosphorus

7 ± 108 %

Total Suspended Solids

67 ± 45 %

5.2.1.2.2.2.- Other UWWTP around the Bay.

Around the Bay there are other SWTP that do not discharge into the marine waters although their effects could be noticed by secondary processes, as rainfall processes. Calvià UWWTP, managed by the public company Calvià 2000, produces treated waters (164,000 m3/year) to be used for irrigation and it discharges to the Torrent Son Boronet, although the water does not reach the mouth of the torrent (Laboratori de l’Aigua unpublished data). The private UWWTP Urb. Sol de Mallorca Puerto and Urb. Sol de Mallorca Playa with volumes of 5000 m3/y and 6000 m3/y respectively, discharge their effluent into a private plain (JAB, 1998 and Laboratori de l'Aigua unpublished data).

5.2.2.- Discharge inputs This subsection discusses, data regarding nutrient emissions as a regular part of the process. In Bay of Palma continuous nutrient emitting sources can be considered the other three major UWWTP in the Bay (Palma II, Bendinat and S’Arenal), the desalination plants (Bay of Palma and Son Tugores) and the thermal power station San Juán de Dios. This section also include marinas and boating infrastructures because these activities take place during all year, so it can be considered as a discharge input.

42

5.2.2.1.- Palma II Urban Waste Water Treatment Plant (data provided by EMAYA, except where referenced) This plant has a physicochemical primary treatment, a biological secondary treatment and tertiary treatment only for urban irrigation. This plant should be able to treat an income flow of 90,000 m3/d. The income flow of this plant is constant during the year, being expected 68,000 m3/d (data from JAB, 1998), but the plant treated 77,756 m3/d during 2001. The total volume of water treated in 2001 was 23,637,880 m3. Water treated by this plant has several uses: for agricultural land irrigation (10,277,846 m3 (43.48%) in 2001), or to the tertiary treatment for urban irrigation (1,821,154 m3 (7.70%) in 2001), or to the outfall, when surplus to that needed for irrigation (11,538,880 m3 (48.82%)). As the figures show, half of the water undergoing secondary treatment, thus preserving the most of the nutrients, is evacuated directly to the sea. This represents one of the constant inputs of nutrient to the coastal ecosystems of the Bay.

EMAYA own to types of outfalls: emergency ones and mixed emergency, exceeds and agricultural uses. For emergencies EMAYA uses two outfalls: - Baluarte: located in front of the Cathedral with diffusion at 17 m depth (figure 19) - San Agustín: located in front of the San Agustín Nautical Club with diffusion at 22 m depth (figure 19)

Figure 19.- Location of the areas where outfalls discharge within the Bay of Palma 43

EMAYA owns one outfall of mixed functions located in front of the mouth of Torrent Gros at 16 m depth. It receives excess water from the secondary treatment of Palma II, apart of emergencies and agricultural water. It is of note that the outfall discharges into the area where Torrent Gros evacuates the water into the bay.

The Environmental Department of the Balearic Government has analysed the outfall of Palma II plant. The data from the analysis done by the Water Laboratory (Laboratori de l’Aigua unpublished data) from 1992 to 2001 are represented in Table 4.

Table 4.- Parameters concentration of Palma II UWWTP

Concentration (mg/l)

Average

Maximum

Minimum

Ammonium

37.74 ± 15.86

62.15

0.55

Nitrate

17.17 ± 22.55

96.06

0.00

Nitrite

0.67 ± 2.19

11.76

0.01

Phosphate

8.77 ± 6.02

20.85

0.59

COD

161.00 ± 85.00

329.00

41.00

BOD5

49.00 ± 26.00

110.00

8.00

Total Suspended Solids

98.00 ± 51.00

230.00

5.00

The efficiency of this plant, calculated using analysis of the inflowing and effluent waters, is expressed in Table 5. Table 5.- Efficiency of Palma II UWWTP (1992-2001 Laboratori de l’Aigua unpublished data) Parameter

Efficiency

COD

80 ± 13 %

BOD5

89 ± 6 %

Total Nitrogen

36 ± 18 %

Total Phosphorus

49 ± 21 %

Total Suspended Solids

78 ± 13 %

44

5.2.2.2.- S'Arenal Urban Waste Water Treatment Plant

The S'Arenal treatment plant is located in the Eastern coast of the Bay of Palma (figure 19), but has become outdated and has been replaced recently by a new one. The late records for nutrients that are available from this old plant are from the end of 2000. The Llucmajor municipality and the company SEARSA managed the plant. The volume treated changed from high occupation periods with 2,990 m3/d to low occupation periods where it was of 2,073 m3/d, although the designed volume for the plant is not available. This plant treated an average of 868,000 m3/year emitting it discharges to the Caleta de Son Verí through an outfall. The plant provided for preliminary treatment and primary treatment with activated sludge (data from JAB, 1998). The plant was closed because its capacity was not sufficient for the growing demand (SEARSA unpublished data). The data from the analysis done by the Water Laboratory (Laboratori de l’Aigua) from 1992 to 2000 are given in Table 6. Table 6.- Parameters concentration of S’Arenal UWWTP Concentration(mg/l)

Average

Maximum

Minimum

34.63 ± 12.89

51.20

0.55

Nitrate

4.26 ± 3.35

13.15

0.00

Nitrite

0.16 ± 0.17

0.85

0.01

Phosphate

15.16 ± 8.75

35.26

0.85

COD

191.00 ± 134.00

654.00

45.00

BOD5

55.00 ± 41.00

220.00

18.00

Total Suspended Solids

72.00 ± 72.00

400.00

18.00

Ammonium

45

The efficiency of this plant, calculated using analysis of the inflowing and effluent waters, was: Table 7.- Efficiency of S’Arenal UWWTP (1992-2001 Laboratori de l’Aigua unpublished data) Parameter

Efficiency

COD

81 ± 15 %

BOD5

90 ± 8 %

Total Nitrogen

46 ± 22 %

Total Phosphorus

44 ± 21 %

Total Suspended Solids

82 ± 23 %

The new plant of S'Arenal is designed to treat waters coming from the Bay of Palma coastal area within the Llucmajor municipality. Although the plant was commissioned on February the 25th 2002, the treatment began on September 2001, working for one month together with the old plant (SCS, the building company, unpublished data). The design data for peak and non-peak times, with equivalent populations of 79,500 and 42,500 and daily incoming flows of 15,900 m3 and 8,500 m3 respectively. The plant will give primary, biological secondary and tertiary treatment to the wastewater, which will be used for garden and golf courses irrigation as well as for street cleaning (elmundo-eldia newspaper 26th February 2002). The predicted results are summarised in table 8. Table 8.- Predicted parameter results for the new S’Arenal UWWTP Parameter

Predicted concentrations

BOD5

< 25 mg/l

Total Nitrogen

< 15 mg/l

Total Phosphorus

< 200 mg/l

Total Suspended Solids

< 35 mg/l

The exceeding water will flow into the Bay through an outfall, where the previous SWTP used to discharge (data provided by SCS, the building company, except where referenced).

46

5.2.2.3.- Bendinat Urban Waste Water Treatment Plant.

The plant, located in the Western side of the Bay, applies daily preliminary treatment, primary treatment with activated sludge and secondary treatment to 8,400 and 1500 m3 of wastewater in peak and non-peak times respectively. The annual volume totals 1,387,000 m3, part of which is used for irrigating the golf club of Bendinat apart of other public irrigations and the rest flow into the bay through an outfall (E013) next to Portals Nous (Figure 19). This plant will be provided of tertiary treatment by the end of the year 2002-beginnings of 2003 (Calvià Municipality webpage). Data from the analysis done by the Water Laboratory (Laboratori de l’Aigua) from 1992 to 2001 show the following figures (table 9)

Table 9.- Parameters concentration of Bendinat UWWTP Concentration (mg/l)

Average

Maximum

Minimum

7.33 ± 9.09

27.26

0.14

Nitrate

18.82 ± 22.29

52.01

0.00

Nitrite

0.27 ± 0.35

1.08

0.01

Phosphate

11.50 ± 10.00

24.47

0.16

COD

62.00 ± 54.00

231.00

11.00

BOD5

8.00 ± 6.00

22.00

0.00

41.00 ± 25.00

88.00

10.00

Ammonium

Total Suspended Solids

The efficiency of this plant, calculated using analysis of the inflowing and effluent waters, is summarised in table 10.

47

Table 10.- Efficiency of Bendinat UWWTP (1992-2001 Laboratori de l’Aigua unpublished data) Parameter

Efficiency

COD

90 ± 9 %

BOD5

97 ± 2 %

Total Nitrogen

62 ± 30 %

Total Phosphorus

35 ± 20 %

Total Suspended Solids

73 ± 54 %

5.2.2.4- Desalination Plants.

Mallorca as a whole consumes almost all of its available water resources such that in dry seasons or in periods of excessive extractions from wells, there is overexploitation (Blàzquez et al, 2002). The increase of population has increased the need of drinking water; drinking water has even been shipped from the Iberian Peninsula (Gual, 2001). Because this demand for drinking water, the administration has promoted the building of desalination plants. These plants extract the salt from marine or brackish water until became drinking by inverse osmosis. The hypersaline discharge (brine) is poured out to the Bay of Palma, thus introducing water with concentrated nutrients to the marine waters. Around the Bay there are three fixed plants and many modular non-fixed stations, the most important of which is that at Son Tugores, which uses brackish water. The desalination plant of the Bay of Palma uses marine water.

5.2.2.4.1- Potabiliser of Son Tugores.

The plant has been operating since 1996 and is managed by the public company EMAYA. The plant has being designed for producing around 30,000 m3/d of water with salinities under 0.5 g/l. It takes brackish water (2-10 g/l salt), the source water is taken from the centre of the island with flows of 25,000 m3/d from Pont d'Inca and 12,500 m3/d. The efficiency of the plant is around 80 % depending on the salinities of the incoming water. The outcoming flow was around 7,500 m3/d (data provided by EMAYA).

48

The flowing water, less salted than the receiving waters (Puigserver et al, 1999), is discharged into the Torrent Riera, which flows into the Palma port waters. Although no analytical data of the discharges was provided the effects of these discharges will be commented in section 6.

5.2.2.4.2.- Bay of Palma desalination plant.

This plant is managed by IBAEN (Balearic Institute for Energy) a public company controlled under the Environmental Department of the Balearic Government. The plant produces an outflow of around of 83,000 m3/d, which flows into the Bay of Palma through an outfall in the city area in front of the Torrent Gros, where Palma II SWTP also discharges (Gual, 2001). In the present, the effluents go into Torrent Gros, because being denser waters if these waters flow into the bay through an outfall they would not mix with the surrounding waters, as happen with UWWTP discharge waters (José María Novoa, IBAEN, pers. comm.) Regarding nutrient composition, the averaged characteristics for the period (April 2001-March 2002) of discharge waters are summarised in table11.

Table 11.- Averaged properties of the water discharged by Bay of Palma desalination plant (04/2001-03/2002)

Salinity (g/l)

Before

After

37.61

69.5

Temperature (o C)

21.8

Silicates (mg/l SiO2)

4.3

5.8

Nitrates (mg/l NO3-)

6.05

1.8 (pers. comm)

Respect silicates data, there is an abnormal value of 7.7 mg/l in the incoming waters; otherwise the average value would be 3.875 mg/l.

5.2.2.4.3.- Other desalination plants.

During the year 2000 were operating some modular stations, temporal installations, placed next to the thermal power station of San Juan de Dios, to supply the demand of

49

fresh water. These installations produced around 79000 m3/d and discharged into the bay through an outfall, located 200 m from the plant, 10 00 m3/d of highly saline water(Gual 2001) in Cala Gamba.

5.2.2.5- Thermal Power Station San Juán de Dios. This central plant was opened in 1968 with a production of 250·106 Kw. Increasing its production up to 109 Kw in the years 1980-1981. In 1982 a new power station was opened on the island, since then the production levels are very irregular. The sharp variations in the discharge water, in volume and temperature, are a new stressing factor added to the average increase in temperature of the area (Alemany, 1990) The thermal power station of San Juán de Dios uses an once through cooling water system, discharging its waters, increased in temperature around 5 oC above ambient, in the small bay of Cala Gamba. The effluent, around 10 m3/s, which flows through a channel of small dimensions located in the shoreline, is not provided with a diffusion systems and thus creates an intense current, around 4 m/s. Thus, the heated plume extends through the surface hundreds of meters (Alemany, 1990). Although, data have been requested from this power station, at the moment of the writing of this report, the company, GESA, has provided no analytical data. It is planned to close for the end October 2002 (El Mundo-El Día newspaper 10th-september-2002). This plant is not a conventional plant because nowadays, in addition to generating energy, an aquaculture plant is being operated. Thus, it outputs should include the nutrients not assimilated by the fish stock (GESA unpublished).

5.2.2.6.- Marinas and boating activities.

Boating is an important sector for the island and especially in a tourism context. The pressure of boating in Mallorca is so strong that a moratorium for building and enlarging the marina infrastructures has been set for the whole island (6th-04-2002 El Mundo-El Día newspaper). The Bay of Palma accumulates the most of these activities in the Island (31% of marinas of the island). The Bay has 13 marinas, two docks a goods and passengers port. Table 12 summarises the number of moorings available, based and in transit for the bay in the year 2000 Blàzquez et al (2002).

50

These figures, however, does not include all the boats around the Bay, according to Blàzquez et al (2002) the registered number of boats in the island was in 2000 31.83% higher than the total moorings in the ports and marinas. This last figure probably included a high number of boats anchored out of the ports. The nutrient inputs that these activities from the ports themselves, by diffusion and advection, and directly by boats, are difficult to quantify especially because of the lack of measurements and studies in these areas. Nevertheless, the influence of these huge concentrations of boats with direct dumping into the sea, apart of cleaning activities using products containing phosphates should also be considered. Apart of direct boating activities as dumping and cleaning, torrents flow into some ports, e.g. Torrent Sa Riera into Palma Port, Torrent de Son Veri into S'Arenal Marina and Torrent Portals Nous into Porto Portals Marina, which can cause an additional input of nutrients into ports and hence the advection of inner port waters into the Bay. Table 12.- Boating infrastructures and number of moorings for Bay of Palma Name

Type

Municipality

Based

Transit

Total

Moorings

Moorings

Moorings

Portals Vells

Marina

Calvià

59

2

61

Palma Nova

Marina

Calvià

72

0

72

Porto Portals

Marina

Calvià

498

156

654

Calanova

Nautic School

Palma

7

207

214

Ca'n Barbara

Dock

Palma

441

0

441

Club de Mar

Marina

Palma

625

0

625

Paseo Maritimo

Marina

Palma

329

92

421

Sant Magi

Dock

Palma

168

0

168

RCN de Palma

Marina

Palma

767

179

946

CN Portixol

Marina

Palma

278

0

278

Puerto Portixol

Marina

Palma

422

0

422

Molina de Llevant

Marina

Palma

145

15

160

Cala Gamba

Marina

Palma

225

25

250

San Antoni Platja

Marina

Palma

318

75

393

S'Arenal

Marina

Llucmajor

557

80

637

4911

831

5742

Total moorings in Bay of Palma

51

5.3.- Diffuse inputs. This section includes nutrient inputs in which the emissions are not through a located and discrete site, and thus cannot be directly measured.

5.3.1. Groundwater discharges.

Using a mathematical model, develop by the hydraulic services of the Balearic Government, the discharge of subterranean water to the sea was assumed as 19·106 m3/year for the whole unit of Palma Plains for 1981 (Servei Hidraulic, 1987); JAB (Balearic Water Board) published similar results of 13.4·106 m3/year (1999).

In the

contiguous area by the East, Llucmajor-Campos hidrogeological unit, Servei Hidraulic assumed discharges to the sea of an order of 9·106 m3/year (Servei Hidraulic, 1987) while JAB (1999) found a much higher value of 17.9·106 m3/year. JAB(1999) estimated, in the same study, outputs from the hydrogeological unit of Na Burguesa, west coast of Bay of Palma, to the sea as 1·106 m3/year. Summarising, the groundwater output to the Bay of Palma should be approximately 30·106 m3/year. Subterranean waters input to the Bay of Palma are very diffused; only estimations balancing the inputs and outputs of water in the hydrogeological units in the area are available to give the assumption that outputs exits (Servei Hidraulic, 1987). In terms of nutrient concentration in Palma plains groundwater, three measurements in different parts of the hydrogeological unit during March 1996 were done (Annex data of ITGE and JAB, 1997) (Table 13)

Table 13.- Groundwater nutrient concentrations in Palma Plains hydrogeological unit. Station NO3 (mg/l)

NO2 (mg/l)

NH4 (mg/l)

SiO2 (mg/l)

P2O5 (mg/l)

West

5

0.00

0.00

11.7

0.00

Center

19

0.14

0.00

18.7

0.00

East

25

0.00

0.00

13.8

0.00

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5.3.2.- Air inputs.

The average atmospheric nitrogen deposition based on Eurostat New Cronos 1997 for the Balearic Islands region ranges 1-5 kg N/ha/year (Commission of the European Communities, 2002). Considering the cycling of phosphorus, the atmosphere plays a minor, though not a negligible role, producing about 50 kg P/ha/yr (Štirn, 1988).

53

Chapter 6.- Effects of the inputs on the Bay. 6.1.- Effects due to torrents inputs. Although they have not been recognised as a major source of nutrients into the Bay of Palma waters, their contribution to the control of the nutrient budget and then to the ecological dynamics within the bay, is recognisable. In section 3, May 1991 cited as an occasion where data were available, because of the relationship between biotic and abiotic parameters and torrent discharges. The flows in the previous months for stations 2 and 3 are summarised below.

Table 14.- Monthly and annual volumes measured in Station 2 and 3 (Source: JAB 1994)

Monthly Volumes (·106 m3)

Annual

February

March

April

May

Sum

Average

1991

1991

1991

1991

March-May

Volume (·106 m3)***

Station 2

2.29*

1.64*

1.23*

1.85*

7.01

1.53

3.50

6.01**

0.47

0.17

10.15

6.56

Torrent Sa Riera Station 3 Torrent Gros * Biggest register for that month in station 2 in the series 1976-1994 ** Biggest register for that month in station 3 in the series 1965-1994 *** Series 1976-1994 for and 2 and series 1965-1994 for station 3

For the analysis only Station 2 and 3 have been considered, as station 1 did not have a complete record for this period. As can be seen in figure 18, station 2 joins other torrents before flowing into the Bay, so inputs to the sea can be greater than these figures. The average of volume transported in four months was much higher than the annual average

54

for the period (1965-1994). This implies high inputs of freshwater into the bay in a relatively short period of time. In May 1991, an extremely high concentration of nitrates appeared in the centre of the Bay (considered as free anthropogenic influence), at approximately 5 μg/l., when it maxima range from 1.5-2 μg/l. (sometimes higher in port areas, 3 μg/l).The same concentration was found for silicates which values ranged, for the period 1989-1992, 0.045-1.9 μg/l . Phosphates during May 1991 were at the background level. Jansá et al (1994) did not found a clear correlation between phosphates and nitrate maximum concentrations, which led them to think that phosphate maxima do not correspond to external outputs, hence explaining this low level of phosphates. The oxygen percentage saturation presented during May 1991 was very high, greater than 130% in the centre of the bay. These high percentages in oxygen were created by a high concentration of phytoplankton, as they correspond to the high concentration in chlorophyll a found in the same area, 2.27 mg m-3, which is very high for an area considered as oligotrophic. At about the same time a peak was observed for zooplankton, captured with a 100 μm mesh, reaching 44 mg dry weight m-3. The sequence of coincidences indicated a major influence of torrential episodes on the dynamics and productivity of the area, affecting all aspects from nutrient contents to phytoplankton and zooplankton biomass, and thus, the total of the trophic chain.

6.2.- Effect of the UWWTP discharges. Gómez et al (1986) found in 1982, that only 5-2 % of the surface radiation reached the bed in the port area (figure 20). Posidonia oceanica was a poor conservation state during the whole year and Caulerpa prolifera was better developed and was the main component of the vegetation. Comparing this data with the rest of the bay shore, the eastern, centre and north-western vegetation were seriously damaged meanwhile in the southwest of the bay, in clearer water with less pollutants and inputs from the coast, there were better develop communities of vegetation (Gómez et al 1986). The study of Gómez et al (1986) determined the effects of outfalls on Posidonia oceanica and they found that close to the Ciudad Jardín outfall, where Palma II UWWTP discharges, the radiation reaching the bed was scarce. The vegetation was in a much degraded state, with only Posidonia oceanica rhizomes being found in March and May

55

1982. The effect over the Posidonia meadow was so strong, that even a periodic improvement in transparency and a decrease in pollution found in November 1982 did not improve the vegetation state. Stations located at both sides of the mouth of the outfall presented Posidonia oceanica in a degraded state, however because of a better water transparency the degradation is not as large as the station located in the outfall.

Figure 20.- Light penetration in the Port of Palma area (Left) in comparison with the centre of the Bay of Palma (Right) (Gómez et al, 1986)

Although Bendinat UWWTP discharges next to one of the stations that was studied in this report, Gómez et al (1986) found in 1982 a high luminosity, bigger than the eastern coast, and corresponding to that at the best developed Posidonia oceanica meadows, accompanied by Caulerpa prolifera and Udotea petiolata.

6.3.- Effects by desalination plants. Emissions into the sea by desalination plants consist in a list of components: corrosion products, antiscaling additives, antifouling additives, halogenated organic compounds formed after chlorine addition, antifoaming additives, anticorrosion additives, oxygen scavengers, oxygen deficiency, acid, heat and finally the brine (Höpner and Windelberg, 1996). Increases in salinity produce some negative effects over marine angiosperms (e.g Posidonia oceanica), such as decrease in production and photosynthesis activity. The brine may be also accompanied as well by higher temperatures than the

56

surrounding waters, which can reduce oxygen concentrations. Terrados in Garcia E. (see references) showed that Caulerpa prolifera meadows stop their growth with salinities over 44 psu, thalli degradation grows as salinity does and at 60%o thalli died fast. The entry with the water of nutrients as phosphates (used as antifouling) and in the brine should be monitored to see possible effects especially in the vegetal cover.

Nutrient loading, have provoked red tide episodes in several parts of the Mallorcan coast, as Soller (Moyà et al, 1993) Andratx port and the Bay of Palma (Puigserver et al, 1999). During 1999, Puigserver et al (1999) observed in the innermost part of Palma Port, in the area where the Torrent Sa Riera has its mouth, red coloured waters which was observed during three weeks. It was not the first time that this bloom was observed; previously red tides appeared in 1995, 1996 and 1997, always occurring at the end of the winter or in the springtime. The red tide was caused by a toxic dinoflagellate Alexandrium minutum Halim, which can produce PSP (Paralytic Shellfish Poisoning) toxins and can produce high biomass concentrations (maximum during the study period 29.39·106 cel/l with the 71% belonging to A. minutum) which can provoke oxygen depletion at the final stages of the bloom and even after it has finished. The causes of the bloom were associated with high nutrient concentrations and the inputs of fresher waters from the desalination plant of Son Tugores, as the plant uses brackish water so the salinity is lower than the marine water. The confined area of the port produced two differentiated layers with a high stability, this factor together with the abundance of nutrients and high temperatures were responsible for the bloom. The end of the bloom occurs with the mixing of the water column and a decrease in temperature because the concentration of nutrients was still very high. The bloom provoked oxygen saturation percentages ranged from 110 % to 300 % and there was a decrease in light penetration because the high planktonic biomass (Puigserver et al, 1999). Alexandrium bloom phenomena have increased in the Mediterranean in recent years and areas created or modified by human activities may be responsible for this increase (Garcés and Masó, 2001)

57

6.4.- Impacts of boating activities. The impacts due to boating activities can be divided in the effects due to activity itself (including fishing activities) and those due to the infrastructures and their maintenance:

6.4.1.- Effects of boating. In the shallower parts of the coast, Posidonia oceanica meadows are influenced by the mechanic action of boats that remove patches of rhizomes (Photography 1). Because boats anchor with bigger frequency in determinate areas (sheltered beaches and bays) these can completely eliminate the meadow. Posidonia oceanica has a slow regeneration rate, and once it goes below the threshold of density loss or anchoring number, the meadow is unable to recover the empty patches, and thus the meadow degrades (Massutí et al, 2000). In deeper waters, principally fishing gears, which remove patches of rhizomes, damage the meadows. In some cases, the outer limit of the meadow is defined by the action of fishing gears (Massutí et al, 2000). Especially important, in term of damage, are trawling gears that “comb” the seabed. Spanish regulations on fishing restrict this class of gears to waters deeper than 50 m., thus their use is not legal in almost the entire of Bay of Palma.

Photography 1.- Portal Nous beach (West of Bay of Palma) with boats anchored and degraded Posidonia meadow in the center (Source: Spanish Ministry of the Environment web page) 58

In addition, boats can contribute to the propagation to the Bay of Palma of the invasive species Caulerpa taxifolia, which was introduced involuntarily in Mallorca waters in 1989 (Pou et al, 1993, Massutí et al, 2000) in Cala d’Or (SE of Mallorca). More recently, in Portocolom (SE of Mallorca, figure 7), near Cala d’Or, Caulerpa taxifolia was also found. The port located in Portocolom Bay then is considered as a possible focus because of being a major anchoring place. This characteristic could facilitate the algal expansion (Riera et al, 1996 in Vicens, 1999)

6.4.2.- Effects of the infrastructures and their maintenance. As an example, the S’Arenal marina in the municipality of Llucmajor will be used for describing the processes and effects that accompany to these infrastructures. The marina of S’Arenal was built during 1978-1979 in a sheltered part of the East of the Bay. Puigserver and Barceló (1990) observed, using aerial pictures from 1956 until 1986, the evolution of benthic communities, since there were no human activities until the changes appreciated after the marina was built. Figure 21.1(1956) show the initial situation with two torrents flowing out in the coast, Torrent de Son Verí (A in the figure) and Torrent dels Jueus (B in the figure) and the Posidonia oceanica meadow. Figure 21.2 (1978) shows the construction of the first marina over a Posidonia meadow and in front of the Torrent del Jueus such that the meadow has completely disappeared. In figures 21.3 (1981) and 21.4(1986) the regression of the meadow can be followed, as well as an increase in rocky shore in the north of the structure which provokes the loss of sand communities and the observed high quantities of Ulva lactuca (Puigserver and Barceló, 1990). After the construction of the eastern dock of Palma, analysis of flora and fauna showed a low water transparency of waters and no Posidonia oceanica elsewhere in the area, neither next to the infrastructure neither in their proximities. Only Ulva lactula was found in the eastern part of the infrastructure, outside the port (Port Authorities unpublished data). Once, the port is built, dredging activities are taken eventually for maintaining the depth within the infrastructure. As an example, S’Arenal marina needs a dredging every three years because sand tends to accumulate inside, as well boats contribute to sedimentation and also a torrent that flows into the port (CBBA, 2001).

59

Figure 21.- The sequence of figures shows the regression of Posidonia oceanica during and after the construction of the S’Arenal Marina ( figure 1 (1956), figure 2 (1978), figure 3(1981) and figure 4 (1986) ) (Source: Puigserver and Barcelo, 1990)

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6.5.- Effects due to thermal emissions in Bay of Palma. Alemany F. J. (1990) found an alteration in communities due to the thermal pollution. The effluent created a permanent thermocline, at 1.2 and 0.4 m depending of the distance from the source. The temperature gradient determines the benthonic communities’ distribution. Aerial photography was used to follow the evolution of the Posidonia oceanica meadow, that initially occupied the whole bay reaching eventually the waters surface. Due to the shallowness of the small bay, benthonic communities were affected by the thermal emissions. Aerial photographs taken two years after the power station construction, showed the destruction of an important part of the Posidonia meadow cover, especially near the outfall and the water extraction area. In 1984 the Posidonia meadow had disappeared from the entire bay, around 9 ha had completely disappeared, being probably more the affected area, and this area was then occupied by Caulerpa prolifera. In the rocky shore around the power station the algal community typical of the area Cystoseira mediterranea, was substituted by other plants more adapted to this stress conditions. Near the outfall well developed beds of Ulva rigida and Enteromorpha sp. were found, substituted in summer by filamental cyanophytes (Alemany, 1990).

6.6. -Conclusions. The effects due to anthropogenic activities can be divided into those effects due to excess nutrients inputs and the indirect effects that could increase the consequences of nutrient addition (ecosystemic approach).

6.6.1.- Effects of nutrient inputs. As Duarte et al (2000) concluded that an increase in nutrient supply would lead to a shift in the biomass distribution, by increasing the autotrophic biomass, particularly that of microphytoplankton, to the detriment of the heterotrophic biomass. When nutrients inputs are low, although the autotrophic biomass is limited, it must supply the carbon demand of heterotrophs, which play an essential role in recycling the nutrients needed to maintain the autotrophic community. If the autotrophic biomass, under high nutrient inputs, exceeds the

61

assimilative capacity of the community to use their production this could, depeding on the dynamics, accumulate and create eutrophication problems. This excess of nutrients benefiting the autotrophic opportunists can change as well the biomass distribution, from a more develop and rich community to a less rich community, where biomass is concentrated in a low number of species (de Jonge & Elliott, 2001). In other terms, the increase observed in Chl a, due to phytoplankton, and the increase of Caulerpa prolifera within the Bay of Palma and the regression of Posidonia oceanica, and all the species richness that conveys, within the bay can illustrate these arguments. Using an ecosystemic approach, the substitution of Posidonia oceanica by less rich biotopes as sandbeds, Ulva lactica and Caulerpa prolifera beds and the increase in the phytoplankton biomass is removing the capacities of Posidonia oceanica to control the ecosystem functionality and act as a nutrient sink. This spiral of ecosystem degradation could lead to wider scale eutrophication symptoms.

6.6.2.- Eutrophication symptoms in Bay of Palma. According to the simplified eutrophication model (figure 1) of Bricker et al (1999), the eutrophication symptoms found in the Bay of Palma could be divided into primary and secondary symptoms.

6.6.2.1.- Primary symptoms in the Bay of Palma.

Primary symptoms represent the first possible stage of water-quality degradation associated with eutrophication. Decreased light availability were found in some restricted areas or close to human infrastructures as ports (especially port of Palma (figure 20) or outfalls, where extreme nutrient and Chl a concentrations where found. In some of these sites, as commented before, the change from Posidonia beds to Caulerpa prolifera or Ulva lactica were found. In the waters close to the coast of the Bay there is observed a loss of visibility, being greener in contrast with the pristine transparency typical of very oligotrophic waters (Dr. Jansá, IEO scientist, pers. comm.). The increase in Chl a in the water column and the decrease of Posidonia coverage, for several reasons, could mean a

62

switch from benthic dominance to pelagic dominance in coastal waters. With respect to increased organic matter decomposition no data were found.

Table 15.- Summary of primary symptoms found in the Bay of Palma

Primary symptoms

Presence of absence in the Bay of Palma

Decreased light availability



Algal dominance changes



Increased organic matter decomposition

Non available Data

6.6.2.2.- Secondary symptoms in the Bay of Palma.

Sometimes, primary symptoms leads to secondary symptoms, however, secondary symptoms can exist without originating from the primary symptoms (Bricker et al, 1999). In coastal waters, loss of submerged aquatic vegetation is found in coastal areas of the Bay of Palma by different reasons (such as high turbidity, outfall discharges, anchoring, boating infrastructures, etc.) however; there are no data available about it tendency. Harmful algae blooms, of Alexandrium minutum Halim, have been reported in the Port of Palma in several years (Puigserver et al, 1999) because of its restricted circulation and receiving waters from a desalination plant in addition to the Torrent Sa Riera inputs. With respect to low dissolved oxygen, although the available data does not indicate low levels of oxygen, the role of Posidonia meadows as a net oxygen producer (Massutí et al, 2000) to the sediment and water column should be regarded and evaluated. There is a lack of knowledge about oxygen concentrations within the sediment.

63

Table 16.- Summary of secondary symptoms found in the Bay of Palma

Secondary symptoms

Presence of absence in the Bay of Palma

Loss of submerged aquatic vegetation



Harmful algae



Low dissolved oxygen

X/ Non available data

6.6.3.- Conclusions. Bay of Palma can be divided, in terms of eutrophication, into two areas. An inshore area which is hypernutrified, especially in summer where the development of stratification does provoke low nutrient contents in the surficial waters which due to the anthropogenic inputs has greater concentrations than the expected for an extremely oligotrophic area. The second area, an offshore area, is neither eutrophic nor hypernutrified but eventually influenced by land nutrient inputs. The inshore area includes places with restricted circulation and receiving high inputs of nutrients that present the most of the eutrophication symptoms, and thus eutrophicated, such as Port of Palma. There is insufficient information for judging other restricted areas in the bay, such as Cala Gamba where the Thermal Power Station San Juán de Dios discharges or other ports and outfall areas.

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Chapter 7.- Enforcement of the EU Directives in the Bay of Palma.

7.1.- Introduction.

Implementation and application of the European Community Directives in Spain and the Balearic Islands is discussed this section. The National and Autonomic Community legislation is taken to have precedence when the implementation is stricter than at the European level. Also Autonomic laws are regard when the offer special protection to aspects discussed in the corresponding European Directive. In table 17, European Directives and their transposition to national and regional normative are summarised, including the authorities responsible of its management in the Balearic Islands.

Table 17.- Correspondence of European Directives in the Spanish and Balearic Islands context and responsible management authorities. European

Spanish legislation

Directive

Balearic

I. Competent Authorities

legislation

in the Balearic Islands

Nitrates Directive

Royal Decree

Environmental

91/676/EEC

261/1996

Department Autonomous Community

Urban Waste Water Water law 29/1985

Municipalities

Treatment

R.D. 849/1986

IBASAN

Directive

R.D. 419/1993

Community)

91/271/EEC

R.D. 1310/1990

and

(Autonomous

Law 10/1998 Bathing

Water R. Decree 927/1988

Quality Directive

Decree 13/1992

Health

Department

of

Autonomous Community

76/160/EEC Habitats

and R. Decree 1193/1998

Species

Directive R. Decree 1997/1995

92/43/EEC

Environmental Department Autonomous Community

65

7.2.- Nitrates Directive 91/676/EEC. The main aim of this directive is to control and reduce water pollution by nitrates resulting from the spreading or discharge of livestock effluents and the excessive use of fertilizers (preface and Art 1). Under this directive, waters affected by pollution and waters which could be affected by pollution if action programmes are not taken should be identified and designated as Nitrate Vulnerable Zones (NVZ), including the areas of land which drain the waters identified, by Member States in accordance with the next criteria (Art 3, 5 and Annex I): 1.- Whether surface freshwaters, in particular those used or intended for the abstraction of drinking water, contain or could contain, if action programmes are not taken, more than the concentration of nitrates laid down in accordance with Directive 75/440/EEC 2.- Whether groundwaters contain more than 50 mg/l nitrates or could contain more than 50 mg/l if action programmes are not taken. 3.- Whether natural freshwater lakes, other freshwater bodies, estuaries, coastal waters and marine waters are found to be eutrophic or in the near future become eutrophic if programme actions are not taken. Barón-Périz et al (1999) concluded about the quality of groundwaters in the Balearic Islands that the majority of the wells in Palma Plains present nitrate concentrations over 100 mg/l, with important areas over 150 mg/l and maximum over 350 mg/l. Under these considerations, the hydrogeological unit Llanos de Palma (Palma plains) should be designated as a NVZ (ITGE and JAB, 1997). The regional government had only designated as NVZ areas with groundwater containing nitrate concentrations over 50 mg/l that are used for public supply (Barón A. Env. Department). In this sense, only one area in the whole island of Mallorca has been designated as NVZ, the unit Llano de Inca-Sa Pobla (North-East of Mallorca) (ITGE and JAB, 1997). This same report recommended the designation of Llano de Palma (Palma Plains) as NVZ in a black list, because of its use as a permeable aquifer, the main agricultural and livestock area of the island (in spite of a decrease in recent years) and that where NO3 exceeds 50 mg/l, the trend was toward an increase (ERM, 1999-2000). The compliance of this Directive by Spain with respect coastal and marine water monitoring data and forecast is regarded as being insufficient by the European Commission (Commission of the European Communities, 2002).

66

7.3.- Urban Waste Water Treatment Directive 91/271/EEC. This directive concerns the collection, treatment and discharge of urban wastewater to prevent the environment from being adversely affected by the disposal of insufficiently treated wastewater (preface and art. 1). This Directive was amended by Directive 98/15/EEC for clarifying its requirements. According to Articles 4 and 5, waste water entering collecting systems should before discharge be subject to secondary treatment by the end of 2000 for all discharges from agglomerations of more than 15000 p.e. (population equivalent) (Art 4.1). The autonomous community implemented this directive by the Decree 13/1992 being more restrictive with the requirements. Both requirements, the Directive and the Decree one, are commented below.

Table 18.- Requirements for non-sensitive areas in the Directive and for discharges on torrents, absorbing wells and humid areas in the Decree; the requirements are consistent for both areas Parameter BOD5

25 mg/l O2

Minimum percentage of reduction 70-90

COD

125 mg/l O2

75

35 mg/l

90 (optional)

Total Solids

Suspended

Concentration

67

Table 19.- Requirements for sensitive areas from urban waste treatment plants to sensitive areas which are subject to eutrophication. Parameters

Concentration

Minimum percentage of Reduction

2 mg/l 80 Total Phosphorus (10.000-100.000 p.e.) 1 mg/l (more than 100.000 p.e.) 15 mg/l (10.000-100.000 p.e.) 70-80 Total Nitrogen 10 mg/l (more than 100.000 p.e.)(1) (1) Alternatively, the daily average must not exceed 20 mg/l. This requirement refers to a water temperature of 12 o C or more during the operation of the biological reactor of the wastewater treatment plant. As a substitute for the condition concerning the temperature, it is possible to apply a limited time of operation, which takes into account the regional climatic conditions. This alternative applies if it can be shown that paragraph 1 of Annex I.D is fulfilled.

According to the article 3 in the Decree 13/1992 (BOCAIB, Official Bulletin of the Balearic Island Autonomous Community), sensitive areas the total phosphorus and total nitrogen concentration are, whatever the population equivalent is, the more restricted values, thus 1 and 10 mg/l respectively (bold in table19).

The Bay of Palma is regarded as a Sensitive Area but not acknowledged to be so, and therefore considered unofficial [26], at the moment of writing this report the designation was still in process. In this term the regional government has followed the precautionary approach and has classified a large amount of coastal areas under this category which do not necessarily show extreme pollution or eutrophication scenarios. The importance of coastal tourism for the economy of the Archipelago, which therefore depends to some extent on the quality of coastal waters, might have been largely weighed in this decision (ERM, 1999-2000) Under the UWWTD Directive, Table 20 summarises the compliance of the plants located around Bay of Palma. Until is officially declared Sensitive Area, Bay of Palma will not be regarded as such. Thus, requirements for non-sensitive areas were used in this table.

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The compliance of the UWWT Directive by the UWWTP located around Bay of Palma are dependent on the way in which the Directive has been implemented by the Spanish Government. However, almost all the wastewater flowing into the bay receives, at least, secondary treatment.

Table 20.- Requirements under UWWTP for non-sensitive areas and results obtained in the different UWWTP located around Bay of Palma.

Directive

BOD5

BOD5

COD

COD

Total S.S.

S.S.

Conc.

%

Conc.

% of

Conc.

% of

mg/l

reduction

mg/l

reduction

mg/l

reduction

25

70-90

125

75

35

90

requirements

(optional)

Palma I

Data Not

Data Not

Data Not

Data Not

Data Not

Data Not

UWWTP

Available

Available

Available

Available

Available

Available

Palma II

49 ± 26

89 ± 6

161± 85

80 ± 13

98 ± 51

78 ± 13

55 ± 41

90 ± 8

191± 134

81 ± 15

72 ± 72

82 ± 23

< 25 mg/l

Data Not

Data Not

Data Not

Data Not

< 35 mg/l

Available

Available

Available

Available

8±6

97 ± 2

62 ± 54

90 ± 9

41 ± 25

73 ± 54

52 ± 7

92 ± 11

238 ± 248

82 ± 19

130 ± 148

67 ± 45

UWWTP S’Arenal old UWWTP S’Arenal new UWWTP (Predicted) Bendinat UWWTP Urbaniz.

S.

C. Dorado

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7.4.- Habitats and Species Directive (92/43/EEC). The aim of this Directive shall be to contribute towards ensuring biodiversity through the conservation of natural habitats and of wild fauna and flora in the European territory of the Member States (hereafter MS) to which the Treaty applies. Measures taken pursuant to this Directive shall be designed to maintain or restore, at favourable conservation status, natural habitats and species of wild fauna and flora of Community interest (Art 2). Understanding for natural habitats, ‘terrestrial or aquatic areas distinguished by geographic, abiotic and biotic features, whether entirely natural or seminatural’ and natural habitats of Community interest, means those which, within Members’ territories are in danger of disappearance in their natural range or have a small natural range or present outstanding examples of typical characteristics of one or more of the six following biogeographical regions: Alpine, Atlantic, Boreal, Continental, Macaronesian and Mediterranean. These habitats of Community interest are listed in Annex I (Art 1) of the Directive. Some of these habitats included in Annex I of the Directive are highlighted and are priority natural habitat types meaning natural habitat types in danger of disappearance, these priority natural habitat types are indicated by an asterisk (*) in Annex I (Art 1). It is especially important for the purposes of this report is to note that Posidonia beds are classified as a priority natural habitat in this Annex. For the purpose of conserving natural habitats and habitats of species a coherent European ecological network of special areas of conservation (SAC) shall be set up under the title Natura 2000. The Natura 2000 network shall include the special protection areas (SPA) classified by the MS pursuant to Directive 79/409/EEC. Some of the obligations for MS are: to endeavour to improve the ecological coherence of Natura 2000 by maintaining, and where appropriate developing, features of the landscape, which are of major importance for wild fauna and flora. They shall establish the necessary conservation measures and take appropriate steps to avoid, in the special areas of conservation, the deterioration of natural habitats and the habitats of species as well. MS shall subject to appropriate assessment of the implications for the sites relating with conservation objectives to any plan or project not directly connected with or necessary to the management of the site but likely to have a significant effect thereon, either individually or in combination with other plans or projects. ‘If, in spite of a negative

70

assessment of the implications for the site and in the absence of alternative solutions, a plan or project must nevertheless be carried out for imperative reasons of overriding public interest, including those of a social or economic nature, the MS shall take all compensatory measures necessary to ensure that the overall coherence of Natura 2000 is protected’ (Art 6(4)). Where the site concerned hosts a priority natural habitat type and/or a priority species, the only considerations which may be raised are those relating to human health or public safety, to beneficial consequences of primary importance for the environment or, further to an opinion from the Commission, to other imperative reasons of overriding public interest (Art 6). The inclusion of Art 6(4) of Habitats Directive in Birds Directive, allow it to take decisions including those of social and economic nature, which carries some threats over protected sites if MS are more interested in the socio-economic approach than in the conservationist one. The Bay supports two Natura 2000 network sites, both of them designated as SPA and SAC: Cap Enderrocat-Cap Blanc and Cap de Cala Figuera. A description of each of them is provided below.

7.4.1.- Cap Enderrocat-Cap Blanc SPA-pSAC (Natura Site Code: ES0000081). This site (figure 22) covers an area of 6023.83 Ha in the SE part of the Bay, from Cap Enderrocat in the E to Cabo Blanco in the SE, which is one of the Bay limits. It is a mixed site, including terrestrial and marine habitats, comprising thirteen habitats included in annex I and two plants listed in annex II. Posidonia oceanica meadows are deemed to be in excellent conservation status covering 19 % of the site. However, by September 2002 no management plan of the site existed (Standard data form for Natura 2000 network, Environment Department).

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Figure 22.-. Cap Enderrocat-Cap Blanc SPA-pSAC location and related features. (Source: modified from Blàzquez et al (2002) The Bay of Palma marine reserve (BOCAIB 104,17th August), managed by the Agriculture and Fisheries department depending on the Autonomous Community Government, is located within the limits of this SAC (figure 22). The activities in the marine reserved are regulated depending on the area; an integral reserve area is located next to Cap Enderrocat where only anchoring is allowed. In the rest of the marine reserve anchoring is always permitted and fishing gears, diving, snorkel fishing, and angling is regulated, while trawling and other enclosure gears are totally forbidden in the whole of the marine reserve. However, as discussed above, anchoring is a big threat for the conservation of Posidonia oceanica meadows (See Section 6.4.1). In order to prevent the operation of in the area and to increase fish production, some artificial reefs were created in the area (Figure 23) as well as in Bay of Palma West coast (Pers. comm. Agriculture and Fisheries Department).

72

Figure 23.- Artificial reefs location in Bay of Palma (Source: modified from map provided by Agriculture and Fisheries Dep.)

7.4.2.- Cap de Cala Figuera SPA-pSAC (Natura Site Code: ES0000074) Cap de Cala Figuera site (Figure 24) comprises 792.58 Ha in the SW; the Eastern part of this site is within Bay limits. The site is mainly terrestrial, but also includes a small marine area. Posidonia oceanica meadows, in good conservation state, were not the principal reason for the designation of the site, only representing one percent of the surface. In addition, this site, at the time of writing this report, does not have a management plan (Standard data form for Natura 2000 network, Environmental Department).

7.4.3.- Posidonia oceanica protection in the Balearic Islands. The Habitats and Species Directive gives protection to Posidonia oceanica meadows, and regards them as a priority natural habitat. In addition, the Agriculture and Fisheries Department of the Balearic Islands prohibited fisheries, aquaculture and shellfish collection that leads to the destruction of marine Phanerogams meadows (or seagrasses) in Balearic archipelago waters, by an order the 21st of September 1993 (Agriculture and Fisheries Department pers. comm.) 73

Figure 24.-. Cap de Cala Figuera SPA-pSAC location and related features. (Source: modified from Blàzquez et al (2002))

7.4.4.- Other protection designations. The aims of the law 1/1991 are to delimit areas of special protection interest to the autonomous community, regarding their ecological, geological and landscape features and to establish territorial and building planning for their protection and conservation. In addition, this law serves to implement the national Law 4/1989 of sites, flora and fauna conservation in the Spanish Kingdom (Art. 1). The implementation consisted in designate additional protection sites to the national ones. The Balearic law establish three different site designations Interesting Special Natural Area (ANEI, Spanish acronym), Interesting Landscape Rural Area (ARIP, Spanish acronym) and Settlement in Interesting Landscape Area (AAPI, Spanish acronym) (Art 2). The National Law has no designated areas in the Bay of Palma area. In Bay of Palma shoreline, three ANEIs were set (Art 3); Cap Enderrocat and Marina de Llucmajor (Figure 22) located within the limits of the SPA and proposed SAC Cap Enderrocat-Cap Blanc, the first ANEI is completely within the pSAC and Marina de Llucmajor only partially. The third one, which coincides in limits with the SPA and pSAC of Cala Figuera, and is referred as Cap de Cala Figuera-Refeubeig ANEI (Figure 24). This

74

same article (Art. 3) designates all the islands, islets and stacks as ANEIs. However, although none of these ANEIs include marine area in their limits, they can alleviate the anthropogenic pressure over the Bay of Palma, by avoiding the increase of population and urbanisations is these areas.

7.5.- Bathing Water Quality Directive (76/160/EEC). This Directive aims to protect the environment and public health, through concerning the quality of bathing water and reducing its pollution, and to protect such water against further deterioration (Preface and Art.1). For this purpose the Directive set up imperative and guide values for microbiological (total coliforms, faecal coliforms, faecal streptococci, salmonella and enteroviruses) and physicochemical values (pH, colour, mineral oils, surface-active substances...), regarding these values (Table 21) data measured in the stations should conform (Art. 5):

1.- 95% of the samples for parameters corresponding to mandatory values 2.- 90% of the samples in all other cases with the exception of total coliform and faecal coliform parameters where the percentage may be 80% and if, in the case of the 5, 10 or 20% of the samples which do not comply 3.- water does not deviate from the parametric values in question by more than 50 , except for microbiological parameters, pH and dissolved oxygen 4.- Consecutive water samples taken at statistically suitable intervals do not deviate from the relevant parametric values.

75

Table 21.- Microbial parameters required for quality bathing waters:

Microbiological

Guide Values

Imperative Values

Minimum

parameters

Sampling Frequency

Total coliforms

500

10000

Fortnightly (1)

Faecal coliforms

100

2000

Fortnightly (1)

Faecal streptococci

100

-

(2)

Salmonella/litre

-

0

(2)

Enteroviruses

-

0

(2)

PFU/10 l (1) When a sampling station taken in previous years produced result which are appreciable better than those in the Annex of the Directive and when no new factor likely to lower the quality of the water has appeared, the competent authorities may reduce the sampling frequency by a factor of 2. (2) Concentration to be checked by the competent authorities when an inspection in the bathing area shows that the substance may be present or that the quality of the water has deteriorated.

The Spanish Health Ministry monitor and designate bathing waters with the following sanitary criteria (Health Ministry website):

Bathing Waters type 2: Waters suitable for bathing, with very good quality. To be declared type 2 these waters must comply simultaneously the following conditions: a) At least 95% of samples will not surpass the imperative values of the next parameters: Total coliforms, faecal coliforms, salmonella, enteroviruses, pH, colour, mineral oils, surface-active substances, phenols and transparency. b) At least 80% of the samples will not overpass the guide values for total coliforms and faecal coliforms parameters. c) At least 90% of the samples will not surpass the guide values of the next parameters: faecal Streptococcus, Transparency, Dissolved oxygen and floating materials.

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Bathing Waters type 1: Good quality waters suitable for bathing: They do fulfil the a) condition but do not b) and/or c) conditions of bathing waters type 2. Bathing Waters type 0: Waters not suitable for bathing. They do not fulfil a) condition of bathing waters type 2.

According to these criteria the bathing water quality in the Bay of Palma for 2001(Spanish Health and Consume Ministry website) show results:



Palma Municipality: All its bathing waters with analysis were water type 2 except Ciudad Jardín with a qualification of 1. Precisely is in Ciudad Jardin where Palma 2 UWWTP, the desalination plant of Bay of Palma and the Torrent Gros flow.





Calvià Municipality: Coastal waters within the Bay are type 2, except: o

Palma Nova Beach: Two of four samples were type 1

o

Magalluf beach: one of three samples was type 1

Llucmajor Municipality: One sample of four in S'Arenal beach was bathing waters type 1, this beach has near S'Arenal marina and the UWWTP of S'Arenal.

According to the European information (Tourist Atlas in European Community website) during the previous ten years (1990-2000) some beaches in Bay of Palma did not comply with the mandatory values. Beaches that breached the law are pointed out in this section for a latter discussion about the possible sources of pollution.







Palma Municipality: o

Can Pere Antoni Beach in 1999 (one of two measurements)

o

Ciudad Jardín Beach 1998 (two of two measurements)

o

Palma Beach 1999 (one of six measurements)

Calvià Municipality: o

Palma Nova Beach 1999 (one of four measurements)

o

Magalluf Beach 1999 (one of three measurements)

Llucmajor Municipality:

o

S’Arenal Beach 1998 (two of four measurements) 77

These data shows that eventually water without sufficient treatment goes through the outfalls located in the near by of these areas. Especially important for Palma and Llucmajor areas are the marine currents clockwise episodes occurring in these areas of the Bay described by Mateu G. (1998) (Figure5) which could cause outfall plumes to migrate back to the coast. In addition, measurements in Bay waters are only done during peak time (MayOctober). Thus, these indicators are insufficient to measure discharges or inputs of untreated waters into the Bay, which could affect fauna and flora in the study area, as well as serve as a precautionary approach for water pollution. In fact, in February 2002 EMAYA has been accused of discharging waters without treatment to the Bay in February 2002 (El Mundo-El Dia newspaper 9th February 2002).

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Chapter 8.- Bay of Palma management.

8.1.- Introduction.

Coastal management in Spain involves all the different authorities from the State authorities to the municipalities. Although some competences belonged to the municipalities, the Ley de Costas 22/88 (Law of the Coast) and its rules approved by the Royal Decree 1471/89, attributed to the national administration the most part of the competencies on coastal management (Spanish Ministry of the Environment webpage, 2002). Coastal management in the Spanish Kingdom is divided by zones between the different authorities: the Spanish Government through its Ministry of the Environment, the Autonomous Community through its Environment Department and the municipalities. The coastal area can be divided in the following areas:



Maritime-Terrestrial Public Domain (MTPD): comprises estuaries and coastal shoreline and the maritime-terrestrial area (area within low tide to high tide marks, beaches, sand dunes, cliffs, swamps and other low lying wetlands.



Transit easement area: Between 6-20 m from the shoreline



Protection easement area: Between 100-200 m from the shoreline (expect areas classified as urban when the law came into force, where is only 20 m)



Influence area: Minimum of 500 m from the shoreline

8.2.- The Spanish Government. According to the Law of the Coast goods of State public domain, in terms of the coast, those determined by the law include the maritime-terrestrial area, beaches, territorial sea and the natural resources in the Economic Exclusive Zone (EEZ) and continental platform. Coastal competences belonging to the State administration are enforced by the General Coastal Direction (Dirección General de Costas) of the Spanish Ministry of the Environment, with the following functions, according to the Decrees 839/1996 and 1894/96 (Spanish Ministry of the Environment 2002):

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a) Determination

of

the

maritime-terrestrial

public

domain

(MTPD)

and,

consequently, granting authorisations in the transit easement area and beach access. b) Management and guidance of the MTPD. c) Realization, supervision and control of studies, projects and works of defence, protection and conservation of all the elements that integrate the MTPD, and in particular the creation, regeneration and nursery of beaches. d) Functional direction of the Coastal Demarcations and Coastal Provincial Services.

8.3.- Balearic Autonomous Community. The Balearic Autonomous Community is responsible of the authorisations in the protection easement areas, without prejudicing the municipalities competences for building licences. In addition, the Autonomous Community is responsible of authorising land emissions to the sea (Spanish Ministry of the Environment webpage).

8.4.- Mallorca Island Government. The Balearic Autonomous Community delegated to the Islands’ Government the right to grant the authorisations referred to building, installations and permitted activities in the protection easement, when it take place in urban land, as the monitoring and sanctioning role of this actuations (BOIB, Official Bulletin of the Balearic Islands, 2001).

8.5.- Municipalities. Urban planning decisions are competence of the municipalities, without affecting the Autonomous Community competence in management plans. In addition, municipalities have competence in monitoring the cleaning state of the beaches (Spanish Ministry of the Environment website). The shoreline of the Bay of Palma is shared by three different municipalities (from West to East): Calvià, Palma de Mallorca and Llucmajor (Figure 25).

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Figure 25.- Municipalities around the Bay of Palma (Source: Modified from http://www.platerritorial.com)

With respect to municipalities management the example of Calvià differs to the rest. This municipality has been awarded at the last UNEP (United Nations Environmental Program) summit, Johannesburg August-September 2002, for the recycling and reduction of residues in the Municipality, carried out by the municipality government through its public services company Calvià 2000. This is one of the multiple awards that the local authorities have received for their management since in 1995 Calvià 2000 started to apply the Local Agenda 21, develop during UNEP Rio de Janeiro Summit in 1992, to reach a sustainable development in one of the most important tourism area in the Balearic Islands. Among a series of decisions, the local authorities set a moratorium for important constructions in coastal areas during five years and a pilot plan for natural conservation of beaches (Calvià municipality webpage). Calvià local authorities are as well part of the European Life-environment project MED-COASTS S-T, Strategies and Tools Toward Sustainable Tourism in Mediterranean Coastal Areas, which funds the implantation of an Integrated Coastal Zone Management.

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8.6.- Marinas and ports management. Marinas in the Bay of Palma are managed by two different authorities, Palma port and its surroundings nautical ports are managed by the national authorities meanwhile the rest of the ports are managed by the autonomous community government through a port service except one that is managed by the sports department. Because of the strong boating pressure over the coast in the Balearic Islands, the Community Government set up the 5th of April 2002 a moratorium on construction and expansion of marinas until a sector plan was created, at least for three years. During this time, marinas could only increase up to the 10% of the available mooring surface (04/06/2002 El Mundo-El Día newspaper). It has been a very polemic decision because of the high demand on moorings in the archipelago, Tomeu Bestard, president of the association of nautical ports of Balearic Islands, calculated that the demand was twice the supply for the year 2002 (04/26/2002 El MundoEl Día newspaper).

8.7.- Ecotourist tax (tax on stays in tourist accommodation enterprises). In 1999, the Balearic Government established the law 12/1999, which created the Tourist Areas Restoration Fund (Fondo de Rehabilitación de Espacios Turísticos). This fund aimed to “redesign and restore tourist areas and to recuperate resources, natural spaces and heritage of tourist importance”. However, this law was suspended because an appeal of unconstitutionality lodged by the central government, until early this year when the Constitutional Court ended its suspension (Ecotourist tax official webpage, 2002) The reasons argued by the Balearic Government were, that tourism is the main industry of the Islands and the number of tourists was increasing, but because of that the use of the resources was very high. The tax is imposed in tourist accommodation enterprises, counted by days or fraction of days, and on average is around 1€ per day per person. After the tourism season this tax is claimed by the government to be included into this fund and used for the purposes mentioned above.

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Chapter 9.- Final discussion and conclusions. 9.1.- Bay of Palma Nutrient Status. The Bay of Palma is a semi enclosed shallow water area in which its dynamics are forced principally by the generally small coastal wind regime, open to the oligotrophic Mediterranean Sea, where no notable river discharges. This area has an intense navigation pressure and high population density around its coasts, because of its importance as a tourism destination. However, the same engine of its economy has been translated in an enormous pressure over its natural resources. The needs of energy, infrastructures, food and urbanisations to support this large tourism industry are the main cause the Bay of Palma environment degradation. The main nutrient inputs into the bay are outfalls of UWWT plants, desalination plants and torrents (storm-water run-off), whose waters have been enriched with agriculture fertilisers, and whose relation with nutrient concentrations for the whole bay have been pointed out in this report. In addition, the Bay of Palma waters receive inputs from a thermal power station, boating activities and their infrastructures, which are numerous in the area, and groundwater waters enriched as well by fertilisers. The effect of these activities in the Bay have affected to the Posidonia oceanica meadows, an endemic seagrass of the Mediterranean Sea classified as natural priority habitat in Habitats Directive. This supports a highly productive and very diverse ecosystem (Bay, 1984 and Romero, 1985 from Moreno et al, 2001) and is considered as the climax community on soft substrata of the Mediterranean infralittoral zone (Pérès and Picard, 1964 from Moreno et al, 2001). The main factor affecting this plant have been an increase in turbidity, construction of coastal infrastructures (such as ports), discharges from UWWT plants and desalination plants, removing of seagrass patches due to anchoring activities, and some fishing techniques. The degradation of this seagrass that previously acted as a nutrient sink and the excess of nutrient inputs in the Bay of Palma coasts have lead to at least hypernutrification and at worst eutrophication. Inputs in the Bay have been discharged into the waters through outfalls in the cases of UWWT plants and the thermal power station, and sometimes have been surficial such as those from the desalination plant discharges through the natural torrents. The counter clockwise marine dynamics were assumed to disperse the discharges to the open 83

Mediterranean, however, the clockwise episodes that occurs in some parts of the Bay (figure 5) could produced accumulation of nutrients in some coastal areas. This accumulation of circumstances, together with discharges in places with restricted circulation (such as ports, small bays, etc...), have led this water mass to present, especially in inshore coastal waters, primary and secondary symptoms of eutrophication. Consequently, inshore coastal waters can be regarded as hypernutrified, especially during summer when stratification conditions develop. In addition, more restricted water bodies as the Port of Palma can be regarded as eutrophicated, where nutrient inputs have resulted in the proliferation of harmful algal blooms. The latter are composed principally by the toxic dinoflagellate Alexandrium minutum Halim which can produce Paralytic Shellfish Poisoning (PSP) toxins, with the consequently hazard to human health. The degradation of the natural marine habitats, and then the loss of a sink for nutrients, jointly with the increases in nutrient inputs could in extreme situations hypernutrify the whole bay, endangering the most important source of tourist revenue to the island economy. The repercussion of implementing the European Directives into the Bay of Palma has been very low, due to fact that the Palma and Bendinat had secondary treatment before the UWWTD came into force, although S’Arenal plant has recently been built. In addition, eventually wastewaters without the sufficient treatment are discharged into the Bay, and there is not certainty that all the old outfalls have been abandon. With respect to Nitrates Directive, although the EU has suggested in a report (ERM, 1999-2000) that San Jordi should be designated as a NVZ, it has not been declared so at present. With respect to the Bathing Waters Directive some beaches eventually do not fulfil the mandatory values of this directive and in the case of the Habitats and Species Directive only a small proportion of the Posidonia oceanica meadows are protected under this Directive within the Bay.

9.2.- Critique of the Study. The local scientists/managers do all perceive the bay to be in a poor state (perception of the Bay is not very alarmist), their view varies from people that have not observed effects, except very locally, in the Bay to other that find the coastal waters leading to eutrophication, as the data provided in this report shows. Although in difference with the

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local perception, torrents and groundwater were not considered important in the regulation of nutrients, and groundwater inputs were considered to be unimportant. The task of collecting the data, has been difficult because of its relative small diffusion of their publications and lack of coordination between the different bodies. In terms of nutrients, different bodies have measured data, as the IEO (Spanish Oceanographic Institute), IMEDEA (Mediterranean Institute of Advanced Studies) and the Health Department of the Autonomous Community. Some of the IEO data were published and others do not and none of the data has been digitalised, thus making more difficult the data treatment and comparison with other data. The Health Department data refer to measurements only during one summer to test the relationship between nutrients and other parameters of the UWWTD and they were not published and practically unknown for the rest of the bodies. There was also a difficulty that units of measurements change depending on the survey/organisation/analyses, or even within these, which therefore prohibits simple comparison between the different sources of data. In addition, some data were not provided for example those of the Thermal Power Station San Juán de Dios were not provided even three months later being requested. Those data are especially important because of the aquaculture installations within the plant, that act as a nutrient source. The lack of the digital raw data has prevented the possibility of statistical analysis between different times and locations. This is important to set the limits of overenrichment within the bay and to establish possible behaviour equations. The different set of stations in different campaigns also creates difficulties in comparing its evolution within time. In addition, the non correspondence in time of different studies in the Bay makes an analysis of effect-response more difficult.

9.3.- Suggestion for further work.

Considering the work done, and the goals achieved, further work could be developed in the following aspects:



Digitalisation and creation of a database including all the marine parameters in the Bay of Palma.



Statistical analysis between different times and locations.

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Modelling the nutrient inputs and the spatially and temporally evolution of their concentrations and the marine parameters.



An analysis of the separation of surficial layer values from bottom layers in the reference station to compare with Bay of Palma stations.



Calculation of the total nutrients, loadings for the Bay of Palma.



Correlation the torrent discharges with the nutrient concentrations in the Bay for a longer period.



The creation of a complete set of data of anthropogenic inputs for the whole of the nutrient concentration series in the Bay of Palma.



Assessing the effects of the coastal dynamics on the direction of outfalls plumes



Defining the critical load of nutrients yielding a critical level of chlorophyll a (Smith et al,1999)



Defining the degree to which current loadings exceed the critical loading values; this latter calculation would provide an estimate of the minimum required load reduction needed to restore acceptable marine water quality (Smith et al, 1999)



Cost Benefit Analysis on implementing the European Directives for the Bay of Palma

9.4.- Recommendations. Considering that tourism is the main engine of the Balearic Islands, and a good ecological image would help to consolidate as tourism destination. The introduction of the ecotourism tax could which could fund some of the following initiatives:



Revision of the state of Posidonia oceanica meadows in the Bay of Palma



Invigilation and revision of the uses of the numerous outfalls in the context of the Bay, in the context of possible illegal discharges.



Further protection of Posidonia oceanica meadows



Transplanting Posidonia oceanica to restore damaged coastal areas, as have been shown with good results in Leghorn (Italy) (Piazzi et al, 2000)



Instauration of the Local Agenda 21 and ICZM to Palma and Llucmajor municipalities, cooperating for the sustainable development of the Bay of Palma.

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Continuous collection of nutrient data and Bathing Water Directive parameters by the Department of Health, for a better control of the outfall emissions.



Regulation of anchoring along the coast of the Bay, establishing measures to avoid removing of Posidonia patches



The adoption of a Monitoring Plan for the early detection of Caulerpa taxifolia in the Bay, under the precautionary approach



Study of correction measures for coastal infrastructures as ports, docks and groins



An evaluation of the Costs and Benefits of the port construction and enlargement

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Chapter 10. – References. Alemany F.J. (1990) Impactos de la contaminación térmica sobre las biocenosis macrofitobentónicas en la zona de Cala Gamba (Bahía de Palma) producida por la central térmica de San Juan de Dios, Bentos, 6, 475-479 Arhonditsis G., Tsirtsis G., Angelidis M.O. and Karydis M. (2000) Quantification of the effects of nonpoint nutrient sources to coastal marine eutrophication: applications to a semi-enclosed gulf in the Mediterranean Sea, Ecological Modelling, 129, 209-227 Barón-Périz A., Gonzalez-Casasnovas C. and Femenia-Carrió G (1999) Piezometria i qualitat de les aigües subterrànies a Balears Memòria any 1998, Junta D’Aigües de Balears (JAB), Govern Balear Blàzquez M., Murray I. And Garau J. M. (2002) El tercer boom: Indicadors de sostenibilitat del turisme de les Illes Balears 1989-1999, CITTIB, first edition BOIB (2001) Ley 2/2001 de y de marzo de atribución de competencias a los consejos insulares en materia de ordenación del territorio, 32, 3467-3470 Bricker S. B., Clement C. G. Pirhalla D. E. Orlando S. P and Farrow D.R.G. (1999) National estuarine eutrophication assessment: effects of nutrients enrichment in the Nation’s estuaries, NOOA Calvià municipality webpage, http//:www.calvia.com CBBA (2001) Club naútico S’Arenal. Caracterización del sedimento marino. Alternativas de gestión de material dragado. Report for the S’Arenal marina administration. Chacártegui G. (1980), Niveaux de pollution dans les eaux littorals des îles Baléares, Ves Jounées Étud. Pollutions, C.I.E.S.M., 521-528 Clark R. B. (1997) Marine pollution, Clarendon Press, Fourth Edition Commision of the European Communities (2002) Implementation of Council Directive 91/676/EEC concerning the protection of waters against pollution caused by nitrates from agricultural sources: Synthesis from year 2000 Member States reports. COM (2002) 407 final, Brussels Council of the European Communities (1976) Council Directive of 8 December 1975 concerning the Quality of Bathing Water (76/160/EEC), Official Journal of the European Communities, L 31 of 05.02.1976 Council of the European Communities (1991) Council Directive of 12 December 1991 concerning the protection of waters against pollution caused by nitrates from agricultural

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sources (91/676/EEC), Official Journal of the European Communities, L 375 of 31.12.1991 Council of the European Communities (1992) Council Directive 92/43/EEC on the conservation of natural habitats and of wild fauna and flora, Official Journal of the European Communities, L 206 of 22.07.1992 Council of the European Communities (1991) Council Directive of 21 May 1991 concerning urban waste water treatment (91/271/EEC). Official Journal of the European Communities, L 135 of 30.5.1991 Duarte C.M., Agustí S., Gasol J.M., Vaqué D. and Vazquez-Dominguez E. (2000) Effect of nutrient supply on the biomass structure of planktonic communities: an experimental test on a Mediterranean coastal community, Marine Ecology Progress Series, 206, 87-95 Ecotourist tax official webpage http://www.ecotaxa.org El Mundo- El Día newspaper website http://www.elmundo-eldia.com Elliot and de Jonge (2002) The management of nutrients and potential eutrophication in estuaries and other restricted water bodies, Hydrobiologia, 00, 1-12 ERM (1999-2000) Verification of Vulnerable Zones identified under the Nitrates Directive and Sensitive Areas identified under the Urban Waste Water Treatment Directive: Reports by country,Environmenal Resource Management report in http://www.europa.eu.int European Environmental Agency (2002) Europe's biodiversity - biogeographical regions and seas, http://reports.eea.eu.int/report_2002_0524_154909/en Eurotroph webpage http://www.ulg.ac.be/oceanbio/eurotroph/ Fedra K. (1988) System analysis and ecological modelling for assessment and control of marine eutrophication, Unesco Reports in Marine Science, 49, 95-107 Fernández de Puelles M. L. (1990) Evolución temporal de la biomasa zooplanctónicaen el mar Balear, Boletín Instituto Español de Oceanografía, 6(1), 95-106 Fernández de Puelles M. L. and Jansá J. (1992) The planktonic evolution biomass in three coastal areas of Palma Bay (Balearic Islands), Science of the Total Environment, supplement, 697-703 Fernández de Puelles M. L., Jansá J., Gomis C., Gras D. and Amengual B. (1997) Variación anual de las principales variables oceanográficas y planctónicas en una estación nerítica del mar Balear, Boletín Instituto Español de Oceanografía, 13(1 & 2), 13-33 Gacia E. and Ballesteros E. (Consulted August-2002) El impacto de las plantas desalinizadoras sobre el medio marino: la salmuera en las comunidades bentónicas mediterráneas, http://circe.cps.unizar.es/spanish/waterweb/ ponen/gacia.pdf 89

Garcés E. and Masó M. (2001) Harmful algae events in the Mediterranean: are they increasing? GOOS news (UNESCO), 11, 9-11 Gómez A., Ribera A. and Chacártegui G. (1986) Estudio de la vegetación marina de la bahía de Palma (Mallorca), Boletín Instituto Español de Oceanografía, 3(1), 29-42 Gual A. (2001) Diagnostico del litoral de la Isla de Mallorca, report for GOB Höpner T. and Windelberg J. (1996) Elements of environmental impact studies on coastal desalination plants, Desalination, 108, 11-18 Instituto Tecnológico Geominero de España (ITGE) and Junta D’Aigües de Balears (JAB) (1997) Identificacion de masas de agua afectadas por nitratos: designación de zonas vulnerables a la contaminación por nitratos de origen agrario report. Jansá J. (1985) Nota sobre el zooplancton de las principales bahías y puertos de Baleares, Boletín Instituto Español de Oceanografía, 2(1), 108-131 Jansá J. and Carbonell A. (1988) Aspectos del plancton de la Bahía de Palma en 1982, Boll. Soc. Hist. Nat. Balears, 32, 93-114 Jansà-Guardiola and Torres (1946) línies de corrent típiques de brisa a Mallorca, http://www.inm.es

Junta D’Aigües de Balears (JAB) (1994), Mantenimiento y explotación de la red foronómica de las Islas Baleares (1993-1994) Junta D’Aigües de Balears (JAB) (1998), Assistència tècnica d’actualització de bases de dades, cartografia digital i edició del pla hidrològic de les Isles Balears i la seva documentació bàsica. Junta D’Aigües de Balears (JAB) (2000), Mantenimiento y explotación de la red foronómica de las Islas Baleares (1999-2000) Junta d'Aigües de Balears (JAB) (1999). Propuesta del Plan Hidrológico de las Islas Baleares. Govern Balear. Karafistan A., Martin J.-M., Rixen M. and Beckers J.M. (2002) Space and time distributions of phosphate in the Mediterranean Sea, Deep-Sea Research I, 49, 67-82 López-Jurado J. L. (1990) Masas de agua alrededor de las Islas Baleares, Boletín Instituto Español de Oceanografía, 6(2), 3-20 Martínez-Polentinos C. (1988) Fitoplancton de la Bahía de Palma de Mallorca (verano 1988), Memory of activities

90

Massutí-Pascual E., Grau-Jofre A. M., Duarte C. M., Terrados J. and Marbà N. (2000) La posidònia: L’alga que no ho és, Direcció General de Pesca (Conselleria d’Agricultura i Pesca, Govern Balear) and “Sa Nostra” Obra Social i Cultural. Mateu G. (1998) Clima y micropaleontología: termómetros biológicos y archivos sedimentarios, "Territoris" (Universitat de les Illes Balears), 1, 225-238 Jansá J., Fernández de Puelles M.L., López-Jurado J.L., Amengual B., Reñones O. and Morillas A. (1994), Variación anual e interanual de los factores fisicoquímico-biológicos generales del medio pelágico de la Bahía de Palma (Islas Baleares, España) desde mayo de 1988 hasta mayo 1992, Informes Técnicos Instituto Español de Oceanografía Moreno D., Aguilera P.A. and Castro H. (2001) Assessment of the conservation status of seagrass (Posidonia oceanica) meadows: implications for monitoring strategy and the decision-making process, Biological Conservation, 102, 325-332 Moyà G. and Martínez-Taberner A. (1993) Una proliferació de fitoplàncton al Port de Sóller (Mallorca, estiu 1991), Boll. Soc. Hist. Nat. Balears, 36, 121-127 Palma Municipality data Piazzi L., Balestri E., Balata D. and Cinelli F. (2000) Pilot transplanting experiment of Posidonia oceanica (L.) Delile to restore a damaged coastal area in the Mediterranean Sea, Biologia Marina Mediterranea, 7(2), 409-411 Pou S., Ballesteros E., Delgado O., Grau A. Ma., Riera F. and Weitzmann B. (1993) Sobre la presencia del alga Caulerpa taxifolia (Vahl) C. Agardh (Caulerpales, Chlorophyta) en aguas costeras de Mallorca, Boll. Soc. Hist. Nat. Balears, 36, 83-90 Puigserver M., Moyà G. and Ramon G. (1999) Proliferació de l’espècie tòxica Alexandrium minutum Halim en el Port de Palma (Mallorca, marc 1999), relació amb les característiques del medi, Boll. Soc. Hist. Nat. Balears, 42, 47-53 Puigserver S. and Barceló R. (1990) Transformaciones de la costa debidas a la construcción del puerto deportivo de S’Arenal (Badia de Palma), Bentos, 6, 481-490 Servei Hidraulic (SH) (1987) Hidrogeología de la Isla de Mallorca, Direcció General D’Obres Públiques, Govern Balear Spanish Health and Consume Ministry website http://www.msc.es (consulted on 22nd/08/2002) Spanish Ministry of the Environment web page http://www.mma.es Spanish National Institute of Meteorolgy http://www.inm.es

91

Štirn J. (1988) Eutrophication in the Mediterranean Sea: Scientific background for the preparation of guidelines on the assessment of receiving capacity for eutrophying substances, Unesco Reports in Marine Science, 49, 161-189 Mallorca Territorial Plan http://www.platerritorial.com Tourist

Atlas

in

European

Community

website

http://europa.eu.int/water/water-

bathing/tourist.html Turley C. M., (1999) The changing Mediterranean Sea – A sensitive ecosystem? Progress in Oceanography, 44, 387-400 Vicens M. A. (1999) Distribució i estat biològic de les comunitats de macròfits bentònics de Portocolom (Mallorca). Detectada la presència de Caulerpa taxifolia (Vahl) C. Agardh, Boll. Soc. Hist. Nat. Balears, 42,179-186 Werner F. E., Viúdez A. and Tintoré J. (1993) An exploratory numerical study of the currents off the southern coast of Mallorca including the Cabrera Island complex, Journal of Marine Systems, 4, 45-66

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