3. RESULTS AND SYNOPTIC DISCUSSION
3.3 Implications of the results in the global context and for local management
3.3.2 Socio-economic implications and management needs
Besides their negative effects on coastal habitats, high nutrient inputs to estuarine and coastal waters also have implications for people’s livelihood in the coastal zone. Pond aquaculture is directly depending on the quality of coastal waters as a source of intake water for the ponds.Deteriorated water quality in adjacent coastal waters has indirect consequences on aquaculture operation themselves by spreading of diseases and harmful algae species with intake water. This has become a worldwide increasing problem because of major crop losses, and has hampered the sustainable development of the aquaculture industry (Lin, 1989; Kautsky et al., 2000; Qi et al., 2004). A deteriorated water quality of adjacent water bodies also rises the costs for pond maintenance, including costs for electricity for paddle wheel aerators or filtration of the intake water (pers. comm. shrimp farmers). Furthermore, it enhances the need for pesticides and antibiotics, which again may have negative effects on the adjacent ecosystems, as well as on the consumers (Gräslund and Bengtsson, 2001; Holmström
et al., 2003). Excessive antibiotic and pesticide use in shrimp farms has e.g. led to import bans of the EU and the US for shrimp from Thailand and China.
In Hainan, prices for shrimp have decreased dramatically within the past ten years. Shrimps were exported to the US and Europe and up to 19 $ per kg shrimp could be gained, whereas in 2008/2009, shrimps and fish were mainly sold within China and prices varied from 2.50 to 4.70 $ per kg shrimp (mean: 4 $ kg-1; n=10;
unpubl. data). This decrease in prices is mainly associated with reduced export possibilities because of excessive antibiotic and pesticide use as a result of a deteriorated water quality in the intake water of the ponds due to coastal eutrophication.
Pond aquaculture, as it is managed in many parts of the world, including Hainan, reflects an unprofitable venture that causes its own run-down by ecosystem degradation. In the future, aquaculture will be an important food production sector.
However, without taking any measures its growth may be hampered due to increasing self-made pollution.
During the past decades, several studies aimed for improvement of the water quality in aquaculture ponds and their effluents. Governments of several countries established regulations in order to reduce the negative impact of aquaculture.
However, it is rarely evaluated, if threshold values are met and in many cases governments do not manage shrimp and fish farming strictly (e.g. Biao and Kaijin, 2007). Technologies that reduce nutrient contamination on and from shrimp and fish ponds exist, though they are seldom employed. Easy and cheap water treatment can be achieved e.g. by culture with macroalgae, that filter the water and serve as additional biomass (e.g. Troell et al., 1999; Nelson et al., 2001; Jones et al., 2002).
Also, natural stands of mangroves inside and around the ponds serve as water purifiers (Robertson and Phillips, 1995; Binh et al., 1997). These techniques have been implemented in selected farms in several countries. A few farms are also certified by eco-labels such as “International Federation of Organic Agricultural Movements (IFOAM)”, “Naturland”, “Global Aquaculture Alliance” that have strict and standardized production regulations and guarantee fish and shrimp to be raised in sustainable culture. There has been a heavily increasing demand for such products, especially in the US and Europe (FAO/NACA/UNEP/WB/WWF, 2006).
In Hainan, a few farms have started to apply integrated aquaculture practices, mainly polyculture of shrimp together with abalone and/or seaweed (Theodore, 2007);
though, this has not been registered in the study area and none of the farms in Hainan is certified by an international eco-label. In our interviews, the majority of shrimp and fish pond owners stated that they would be open for further training and would like to
learn about better cultivation practices. This shows the potential for eco-friendly farming in the area. Treatment of aquaculture effluents would not only benefit the surrounding coastal habitats, but also the aquaculture industry by minimizing the risk of diseases and harmful algal blooms spreading with contaminated intake water. This in turn, would decrease the need for excessive application of antibiotics and pesticides, guaranteeing a better quality of the crops and potentially better prices. Besides that, the increasing tourism industry in Hainan would benefit from improved water quality of coastal waters.
Apart from water treatment, farm placement in direct vicinity to back-reef areas should be avoided to sustain the health of coastal habitats and their associated communities.
KEY FINDINGS related to the global context and local management:
x Previous studies on global nutrient export have underestimated the role of coastal pond aquaculture as a nutrient source to the coastal ocean in terms of
- an additional nutrient input into coastal waters independent from precipitation runoff
- continuous eutrophication effects in the coastal zone in addition to pulsed effects
x In (sub)tropical areas with large-scale aquaculture, such as SE Asia, current and future nutrient inputs to the coasts may even be higher than widely expected
x The following management measurements are recommended:
- to reduce direct nutrient and OM inputs into estuaries and coasts by e.g. treatment of urban effluents, optimization of fertilizer application on agriculture fields, reduction of water exchange in aquaculture ponds, polyculture and treatment of aquaculture effluents (e.g. with macroalgae)
- to reduce the water transport from land to sea by e.g.
reforestation of mangroves and river bed renaturation
- to optimize the positioning of aquaculture ponds by e.g.
removing aquaculture ponds from sensitive back-reef areas
4. REFERENCES
Alongi, D.M., 2002. Present state and future of the world’s mangrove forests.
Environmental Conservation 29, 331-349.
Alvarez-Cobelas, M., Angeler, D.G., Sanchez-Carrillo, S., 2008. Export of nitrogen from catchments: a worldwide analysis. Environmental Pollution 156, 261-269.
Anderson, D.M., 1997. Turning back the harmful red tide. Nature 388, 513-514.
Anderson, D.M., Glibert, P.M., Burkholder, J.M., 2002. Harmful algal blooms and eutrophication: nutrient sources, composition, and consequences. Estuaries 25, 704-726.
Arar, E.J., Collins, G.B., 1997. “In vitro” determination of Chlorophyll a and Pheophytin a in marine and freshwater phytoplankton by fluorescence. EPA, Cincinnati.
(EPA method 445.0).
Bach, S.S., Borum, J., Fortes, M.D., Duarte, C.M., 1998. Species composition and plant performance of mixed seagrass beds along a siltation gradient at Cape Bolinao, The Philippines. Marine Ecology Progress Series 174, 247-256.
Balls, P.W., Macdonald, A., Pugh, K., Edwards, A.C., 1995. Long-term nutrient enrichment of an estuarine system: Ythan, Scotland (1958-1993).
Environmental Pollution 90, 311-325.
Bao, H., Wu, J., Unger, D., Herbeck, L.S., Du, J., Sun, Y., Zhang, J., submitted.
Sources and diagenesis of organic matter in a sediment core in mangrove tidal flat during the past 100 years - a multi-biomarker approach. Continental Shelf Research.
Beck, M.W., Heck Jr., K.L., Able, K.W., Childers, D.L., Eggleston, D.B., Gillanders, B.M., Helpern, B., Hays, C.G., 2001. The identification, conservation, and management of estuarine and marine nurseries for fish and invertebrates.
BioScience 51, 633-641.
Bell, P.R.F., 1992. Eutrophication and coral reefs - some examples in the Great Barrier Reef lagoon. Water Research 26, 553-568.
Beman, M.J., Arrigo, K.R., Matson, P.A., 2005. Agricultural runoff fuels large phytoplankton blooms in vulnerable areas of the ocean. Nature 434, 211-214.
Biao, X., Kaijin, Y., 2007. Shrimp farming in China: Operating characteristics, environmental impact and perspectives. Ocean and Coastal Management 50, 538-550.
Biggs, T.W., Dunne, T., Martinelli, L.A., 2004. Natural controls and human impacts on stream nutrient concentrations in a deforested region of the Brazilian Amazon basin. Biogeochemistry 68, 227-257.
Billen, G., Garnier, J., 2007. River basin nutrient delivery to the coastal sea: assessing its potential to sustain new production of non-siliceous algae. Marine Chemistry 106, 148-160.
Binh, C.T., Phillip, M.J., Demaine, H., 1997. Integrated shrimp-mangrove farming systems in the Mekong delta of Vietnam. Aquaculture Research 28, 599-610.
Boonphakdee, T., Fujiwara, T., 2008. Temporal Variability of nutrient budgets in a tropical river estuary: the Bangpakong River Estuary, Thailand. Environment Asia 1, 7-21.
Borum, J., Pederson, O., Greve, T.M., Frankovich, T.A., Zieman, J.C., Fourqurean, W., Madden, C.J., 2005. The potential role of plant oxygen and sulphide dynamics in die-off events of the tropical seagrass, Thalassia testudinum. Journal of Ecology 93, 148-158.
Bouwman, A.F., Beusen, A.H.W., Billen, G., 2009. Human alteration of the global nitrogen and phosphorus soil balances for the period 1970-2050. Global Biogeochemical Cycles 23, 1-16.
Boyd, C.E., Tucker, C.S., 1998. Pond aquaculture water quality management. Kluwer Academic Publisher, Boston, MA, 700 pp.
Boyer, E.W., Howarth, R.W., Galloway, J.N., Dentener, F.J., Green, P.A., Vorosmarty, C.J., 2006. Riverine nitrogen export from the continents to the coasts. Global Biogeochemical Cycles 20, p. 1-9.
Boynton, W.R., Kemp, W.M., Keefe, C.W., 1982. A comparative analysis of nutrients and other factors influencing estuarine phytoplankton production. In: Kennedy, V.S. (Ed.), Estuarine Comparisons. Academic Press, New York, pp. 69-90.
Brady, N.C., 1990. The nature and properties of soils, Macmillan, New York.
Braga, E.S., Bonetti, C.V.D.H., Burone, L., Bonetti Filho, J., 2000. Eutrophication and bacterial pollution caused by industrial and domestic wastes at the Baixada Santista Estuarine System, Brazil. Marine Pollution Bulletin 40, 165-173.
Briggs, M.R.P., Funge-Smith, S.J., 1994. A nutrient budget of some intensive marine shrimp pond in Thailand. Aquaculture and Fisheries Management 25, 789-811.
Brodie, J.E., Devlin, M., Haynes, D., Waterhouse, J., 2011. Assessment of the eutrophication status of the Great Barrier Reef lagoon (Australia).
Biogeochemistry 106, 281-302.
Cabaço, S., Santos, R., Duarte, C.M., 2008. The impact of sediment burial and erosion on seagrasses: A review. Estuarine Coastal and Shelf Science 78, 354-366.
Campbell, S.J., McKenzie, L.J., 2004. Flood related loss and recovery of intertidal seagrass meadows in southern Queensland, Australia. Estuarine, Coastal and Shelf Science 60, 477-490.
Canadell, J.G., Pataki, D.E., Pitelka,L.F., 2007. Terrestrial Ecosystems in a Changing.
World. Global Change – The IGBP Series. Springer, 323 pp.
Carlson, P.R., Yarbro, L.A., Barber, T.R., 1994. Relationship of sediment sulfide to mortality of Thalassia testudinum in Florida Bay. Bulletin of Marine Science 54, 733-746.
Castro, M.S., Driscoll, C.T., Jordan, T.E., Reay, W.G., Boynton, W.R., 2003. Sources of nitrogen to estuaries in the United States. Estuaries 26, 803-814.
Chai, C., Yu, Z., Song, X., Cao, X., 2006. The status and characteristics of eutrophication in the Yangtze River (Changjiang) Estuary and the adjacent East China Sea, China. Hydrobiologia 563, 313-328.
Chen, N., Hong, H., 2011. Nitrogen export by surface runoff from a small agricultural watershed in southeast China: seasonal pattern and primary mechanism.
Biogeochemistry 106, 311-321.
Cline, J.D., 1969. Spectrophotometric determination of hydrogen sulphide in natural waters. Limnology and Oceanography 14, 454-458.
Cloern, J.E., 2001. Our evolving conceptual model of the coastal eutrophication problem. Marine Ecology Progress Series 210, 223-253.
Conley, D.J., Schelske, C.L. and Stoermer, E.F., 1993. Modification of the biogeochemical cycle of silica with eutrophication. Marine Ecology Progress Series 101, 179-192.
Costanza, R., d'Arge, R., de Groot, R., Farber, S., Grasso, M., Hannon, B., Limburg, K., et al., 1997. The value of the world’s ecosystem services and natural capital.
Nature 387, 253-260.
Costanzo, S.D., O’Donohue, M.J., Dennison, W.C., 2004. Assessing the influence and distribution of shrimp pond effluent in a tidal mangrove creek in north-east Australia. Marine Pollution Bulletin 48, 514-525.
Creel, L., 2003. Ripple effects: population and coastal regions. Population Reference Bureau, http://www.prb.org/pdf/RippleEffects_Eng.pdf
Dalsgaard, T., Krause-Jensen, D., 2006. Monitoring nutrient release from fish farms with macroalgal and phytoplankton bioassays. Aquaculture 256, 302-310.
Davis, J.R., Koop, K., 2006. Eutrophication in Australian rivers, reservoirs and estuaries - a southern hemisphere perspective on the science and its implications. Hydrobiologia 559, 23-76.
den Hartog, C., 1994. Suffocation of a littoral Zostera bed by Enteromorpha radiata.
Aquatic Botany 47, 21-28.
Diaz, R.J., Rosenberg, R., 1995. Marine benthic hypoxia: A review of its ecological effects and the behavioral responses of benthic macrofauna. Oceanogr. Mar.
Biol. Ann. Rev. 33, 245-303.
Diaz, R.J., Rosenberg, R., 2008. Spreading dead zones and consequences for marine ecoystems. Science 321, 926-929.
Driscoll, C., Whitall, D., Aber, J., Boyer, E., Castro, M., Cronan, C., Goodale, C., Groffman, P., Hopkinson, C., Lambert, K., Lawrence, G., Ollinger, S., 2003.
Nitrogen pollution in the northeastern United States: Sources, effects, and management options. Bioscience 53(4), 357-374.
Duarte, C.M., 1995. Submerged aquatic vegetation in relation to different nutrient regimes. Ophelia 41, 87-112.
Duarte C.M., 2002. The future of seagrass meadows. Environmental Conservation 29, 192-206.
Duce, R.A., LaRoche, J., Altieri, K., Arrigo, K.R., Baker, A.R., Capone, D.G., Cornell, S., Dentener, F., Galloway, J., 2008. Impacts of atmospheric anthropogenic nitrogen on the open ocean. Science 320, 893-897.
Erftemeijer, P.L.A., Herman, P.M.J., 1994. Seasonal changes in environmental variables, biomass, production and nutrient contents in two contrasting tropical intertidal seagrass beds in South Sulawesi, Indonesia. Oecologia 99, 45-59.
Evrard, V., Kiswara, W., Bouma, T.J., Middelburg, J.J., 2005. Nutrient dynamics of seagrass ecosystems: 15N evidence for the importance of particulate organic matter and root systems. Marine Ecology Progress Series 295, 49-55.
Eyre, B., Balls, P., 1999. A comparative study of nutrient behaviour along the salinity gradient of tropical and temperate estuaries. Estuaries 22, 313-326.
FAO/NACA/UNEP/WB/WWF, 2006. International principles for responsible shrimp farming. Network of Aquaculture Centres in Asia-Pacific (NACA). Bangkok, Thailand. 20 pp.
FAO, 2010. The State of World Fisheries and Aquaculture 2010. FAO fisheries and aquaculture department. Rome, 197 pp.
Fischer, G., 1991. Stable carbon isotope ratios of plankton carbon and sinking organic matter from the Atlantic sector of the Southern Ocean. Marine Chemistry 35, 581-596.
Foley, J. A., DeFries, R., Asner, G., Barford, C., 2005. Global consequences of land use. Science 309, 570-574.
Fossing, H., Jørgensen, B.B., 1989. Measurement of bacterial sulfate reduction in sediments: evaluation of a single-step chromium reduction method.
Biogeochemistry 8, 205-222.
Frankovich, T.A., Fourqurean, J.W., 1997. Seagrass epiphyte loads along a nutrient availability gradient, Florida Bay, USA. Marine Ecology Progress Series 159, 37-50.
Frederiksen, M.S., Holmer, M., Borum, J., Kennedy, H., 2006. Temporal and spatial variation of sulphide invasion in eelgrass (Zostera marina) as reflected by ist sulfur isotopic composition. Limnology and Oceanography 51, 2308-2318.
Galloway, J.N., Townsend, A.R., Erisman, J.W., Bekunda, M., Cai, Z., Freney, J.R., Martinelli, L.A., Seitzinger, S.P., Sutton, M.A., 2008. Transformation of the nitrogen cycle: recent trends, questions, and potential solutions. Science 320, 889-892.
Gerlach, S.A., 1990. Nitrogen, phosphorus, plankton and oxygen deficiency in the German Bight and in Kiel Bay. Kieler Meeresforschungen, Sonderheft 7, 1-341.
Glasgow, H.B., Burkholder, J.M., 2000. Water quality trends and management implications from a five-year study of a eutrophic estuary. Ecological Applications 10, 1024-1046.
Gräslund, S., Bengtsson, B.E., 2001. Chemicals and biological products used in south-east Asian shrimp farming, and their potential impact on the environment - a review. Science of the Total Environment 280, 93-131.
Grasshoff, K., Kremling, K., Ehrhardt, M., 1999. Methods of seawater analysis, third ed.
Wiley-VCH, Weinheim, 600 pp.
Grisi, B., Grace, C., Brookes, P.C., Bendetti, A., Dell’abate, M.T., 1998. Temperature effects on organic matter and microbial biomass dynamics in temperate and tropical soils. Soil Biology and Biochemistry 30, 1309-1315.
Hadwen, W.L., Arthington, A.H., 2007. Food webs of two intermittently open estuaries receiving 15N-enriched sewage effluent. Estuarine, Coastal and Shelf Science 71, 347-358.
Hagy, J.D., Boynton, W.R., Keefe, C.W., Wood, K.V., 2004. Hypoxia in Chesapeak Bay, 1950-2001: Long-term change in relation to nutrient loading and river flow.
Estuaries 27, 634-658.
Hallegraeff, G.M., 1993. A review of harmful algal blooms and their apparent global increase. Phycologia 32, 79-99.
Harding Jr., L.W., Perry, E.S., 1997. Long-term increase of phytoplankton biomass in Chesapeake Bay, 1950-1994. Marine Ecology Progress Series 157, 39-52.
Heck Jr., K.L., Pennock, J.R., Valentine, J.F., Coen, L.D., Sklenar, S.A., 2000. Effects of nutrient enrichment and small predator density on seagrass ecosystems: an experimental assessment. Limnology and Oceanography 45, 1041-1057.
Heisler, J., Glibert, P.M., Burkholder, J.M., Anderson, D.M., Cochlan, W., Dennison, W.C., Dortch, Q., Gobler, C.J., Heil, C.A., Humphries, E., Lewitus, A., Magnien, R., Marshall, H.G., Sellner, K., Stockwell, D.A., Stoecker, D.K., Suddleson, M., 2008. Eutrophication and harmful algal blooms: A scientific consensus. Harmful Algae 8, 3-13.
Hemminga M, Duarte C.M., 2000. Seagrass Ecology. Cambridge University Press.
Herbeck, L.S., Unger, D., Krumme, U., Liu, S.M., Jennerjahn, T.C., 2011. Typhoon-induced precipitation impact on nutrient and suspended matter dynamics of a tropical estuary affected by human activities in Hainan, China. Estuarine, Coastal and Shelf Science 93, 375-388.
Hinrichsen, D., 1994. Coasts under pressure. People Planet 3, 6-9.
Holmer, M., Frederiksen, M., Mollegaard, H., 2005. Sulfur accumulation in eelgrass (Zostera marina) and effect of sulphur on eelgrass growth. Aquatic Botany 81, 367-379.
Holmes, R.M., McClelland, J.W., Sigman, D.M., Fry, B., Peterson, B.J., 1998.
Measuring 15N-NH4 in marine, estuarine and fresh waters: An adaptation of the ammonia diffusion method for samples with low ammonium concentrations.
Marine Chemistry 60: 235-243.
Holmström, K., Gräslund, S., Wahlström, A., Poungshompoo, S., Bengtsson, B.E., Kautsky, N., 2003. Antibiotic use in shrimp farming and implications for
environmental impacts and human health. International Journal of Food Science and Technology 38, 255-266.
Hopkins, J.S., Hamilton, R.D., Sandier, P.A., Browdy, C.L., Strokes, A.D., 1993. Effect of water exchange rate and production, water quality, effluent characteristics and nitrogen budgets of intensive shrimp ponds. Journal of the World Aquaculture Society 24, 304-320.
Howarth, R.W., 1988. Nutrient limitation of net primary production in marine ecosystems. Annual Review of Ecology 19, 89-110.
Howarth, R.W., Billen, G., Swaney, D., Townsend, A., Jaworski, N., Lajtha, K., Downing, J.A., Elmgren, R., Caraco, N., Jordan, T., Berendse, F., Freney, J., Kudeyarov, V., Murdoch, P., Zhu, Z.L., 1996. Regional nitrogen budgets and riverine N and P fluxes for the drainages to the North Atlantic Ocean: natural and human influences. Biogeochemistry 35, 75-139.
Howarth, R.W., Swaney, D.P., Boyer, E.W., Marino, R., Jaworski, N., Goodale, C., 2006. The influence of climate on average nitrogen export from large watersheds in the Northeastern United States. Biogeochemistry 79, 163-186.
Howarth, R.W., Teal, J.M., 1979. Sulfate reduction in a New England salt marsh.
Limnology and Oceanography 24, 999-1013.
Huang, L., 2003. Conflicts between ecology and economy and possible solutions: a case study from Hainan Province, South-China. Dissertation, Freiburg (Breisgau)-University, 310 pp (in German).
http://www.freidok.unifreiburg.de/volltexte/1349/pdf/OekoHL08.pdf
Hughes, B.B., Haskins, J.C., Wasson, K., Watson, E., 2011. Identifying factors that influence expression of eutrophication in a central California estuary. Marine Ecology Progress Series 439, 31-43.
Humborg, C., Ittekkot, V., Cociasu, A., van Bodungen, B., 1997. Effect of Danube River dam on Black Sea biogeochemistry and ecosystem structure. Nature 386, 385-388.
Humborg, C., Danielasson, A, Sjöberg, B., Green, M., 2003. Nutrient land–sea fluxes in oligothrophic and pristine estuaries of the Gulf of Bothnia, Baltic Sea. Estuarine Coastal and Shelf Science 56, 781-793.
IPCC, 2011. Summary for Policymakers. In: Field, C. B., Barros, V., Stocker, T.F., Qin, D., Dokken, D., Ebi, K.L., Mastrandrea, M. D., Mach, K. J., Plattner, G.-K., Allen, S. K., Tignor, M. and P. M. Midgley (eds.): Intergovernmental Panel on Climate Change Special Report on Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation. Cambridge University Press, Cambridge, United Kingdom and New York.
Jackson, C., Preston, N., Thompson, P.J., Burford, M., 2003. Nitrogen budget and effluent nitrogen components at an intensive shrimp farm. Aquaculture 218, 397-411.
Jennerjahn, T.C., Knoppers, B.A., de Souza, W.F.L., Brunskill, G.J., Silva, E.I.L, 2006.
Factors controlling dissolved silica in tropical rivers. In: Ittekkot, V., Unger, D., Humborg, C., Tac An, N. (eds.). The Silicon Cycle. Human Perturbations and
Impacts on Aquatic Systems. SCOPE 66, Island Press, Washington D.C., 29-51.
Jones, A.B., O’Donohue, M.J., Udy, J., Dennison, W.C., 2001. Assessing ecological impacts of shrimp and sewage effluent: biological indicators with standard water quality analyses. Estuarine, Coastal and Shelf Science 52, 91-109.
Jones, A.B., Preston, N.P., Dennison, W.C., 2002. The efficiency and condition of oysters and macroalgae used as biological filters of shrimp farm effluent.
Aquaculture Research 33, 1-19.
Kaplan, I.R., Emery, K.O., Rittenberg, S.C., 1963. The distribution and isotopic abundance of sulphur in recent marine sediments off southern California.
Geochimica et Cosmochimica Acta 27, 297-331.
Kautsky, N., Rönnbäck, P., Tedengren, M., Troell, M., 2000. Ecosystem perspectives on management of disease in shrimp pond farming. Aquaculture 191, 145-161.
Kirkman, H., 1996. Baseline and monitoring methods for seagrass meadows. Journal of Environmental Management 47, 191-201.
Krumme, U., Wang, T.C., Wang, D.R., submitted. From food to feed: assessment of the stationary lift net fishery in East Hainan, South China Sea. Continental Shelf Research.
Lee, K.-S., Bong, Y.-S., Lee, D., Kim, Y., Kim, K., 2008. Tracing the sources of nitrate in the Han River watershed in Korea, using į15N-NO3- and į18O-NO3- values.
Science of the Total Environment 395, 117-124.
Lin, C.K., 1989. Prawn culture in Taiwan, what went wrong? World Aquaculture 20, 19-20.
Lin, D.T., Fong, P., 2008. Macroalgal bioindicators (growth, tissue N, į15N) detect nutrient enrichment from shrimp farm effluent entering Opunohu Bay, Moorea, French Polynesia. Marine Pollution Bulletin 56, 245-249.
Likens, G., 1972. Eutrophication and Aquatic Ecosystem. Nutrient and Eutrophication.
Limnology and Oceanography, Special Symposia Volume I, 3-13.
Lirman, D., Cropper Jr., W.P., 2003. The Influence of salinity on seagrass growth, survivorship, and distribution within Biscayne Bay, Florida: field, experimental, and modeling studies. Estuaries 26, 131-141.
Lorenzen, C.J., 1967. Determination of chlorophyll and pheo-pigments:
spectrophotometric equations. Limnology and Oceanography 12, 343-346.
Lotze, H.K., Lenihan, H.S., Bourque, B.J., Bradbury, R.H., Cooke, R.G., Kay, M.C., Kidwell, S.M., Kirby, M.X., Peterson, C.H., Jackson, J.B.C., 2006. Depletion, degradation, and recovery potential of estuaries and coastal seas. Science 312, 1806-1809.
McClelland, J.W., Valiela, I., Michener, R.H., 1997. Nitrogen-stable isotope signatures in estuarine food webs: A record of increasing urbanization in coastal watersheds. Limnology and Oceanography 42, 930-937.
McGlathery, K.J., 1995. Nutrient and grazing influences on a subtropical seagrass community. Marine Ecology Progress Series 122, 239-252.
McGlathery, K.J., 2001. Macroalgal blooms contribute to the decline of seagrass in nutrient-enriched coastal waters. Journal of Phycology 37 (4), 453-456.
Montgomery, M.R., 2008. The urban transformation of the developing world. Science 319, 761-764.
Nagelkerken, I., van der Velde, G., Gorissen, M.W., Meijer, G.J., Van't Hof, T., den Hartog, C., 2000. Importance of mangroves, seagrass beds and the shallow coral reef as a nursery for important coral reef fishes, using a visual census technique. Estuarine, Coastal and Shelf Science 51, 31-44.
Neckles, H.A., Wetzel, R.L., Orth, R.J., 1993. Relative effects of nutrient enrichment and grazing on epiphyte-macrophyte (Zostera marina L.) dynamics. Oecologia 93, 285-295.
Nicholls, R.J. Wong, P.P., Burkett, V.R., Codignotto, J.O., Hay, J.E., McLean, R.F., Ragoonaden, S., Woodroffe, C.D., 2007. Coastal systems and low-lying areas.
In Parry, M.L., Canziani, O.F., Palutikof, J.P., van der Linden, P.J., Hanson, C.E. (eds.). Climate Change 2007: Impacts, Adaptation and Vulnerability.
Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Cambridge University Press, Cambridge, UK, 315-356.
Nixon, S.W., Pilson, M.E.Q., 1983. Nitrogen in estuarine and coastal marine ecosystems. In: Carpenter, E.J., Capone, D.G. (eds.). Nitrogen in the Marine Environment. Academic Press, New York, 565-648.
Nixon, S. W., 1995. Coastal marine eturophication: A definition, social causes, and future concerns. Ophelia 41, 199-219.
Maier, D., 2010. Variabilität des Phytoplanktons im tidenbeeinflussten Wenchangästuar, Ost-Hainan, Südchinesisches Meer. Diploma thesis, Universität Bremen, 110 pp.
Martin, S., Rodolfo-Metalpa, R., Ransome, E., Rowley, S., Buia, M.C., Gattuso, J.P., Hall-Spencer, J., 2008. Effects of naturally acidified seawater on seagrass calcareous epibionts. Biology Letters 4, 689-692.
Martinelli, L.A., Ballester, M.V., Krusche, A.V., Victoria, R.L., Camargo, P.B., Bernardes, M., Ometto, J.P.H.B., 1999. Land cover change and į13C
Martinelli, L.A., Ballester, M.V., Krusche, A.V., Victoria, R.L., Camargo, P.B., Bernardes, M., Ometto, J.P.H.B., 1999. Land cover change and į13C