Abstract
This work utilizes the CoastWeb model, a foodweb model for coastal areas that also includes a mass-balance model (CoastMab) for phosphorus and many abiotic/biotic interactions, to study the development in Ringkøbing Fjord, Denmark, from 1985 to 2004. This shallow coastal lagoon has an area of 300 km2 and a mean depth of 1.9 m. The water exchange between the lagoon and the North Sea is regulated by a sluice. In 1996 there was a major regime shift in this lagoon with drastic reductions in chlorophyll-a concentrations, significant increases in water clarity (Secchi depth) and major changes in the number and biomass of clams as well as in macrophyte cover. Regime shifts is a “hot” topic in aquatic ecology and in this work the CoastWeb model is used as a tool to understand and quantify the causes behind this regime shift. The CoastWeb model is general and can also be used for other coastal areas. The basic model calculates monthly production values and changes in biomasses of ten functional groups of organisms (phytoplankton, bacterioplankton, herbivorous, and predatory zooplankton, benthic algae, macrophytes, jellyfish, zoobenthos and prey and predatory fish) and in Ringkøbing Fjord, also for clams (Mya arenaria). In spite of its complexity, the model is relatively simple to use, since all driving variables may be readily accessed from maps or monitoring programs. The model includes much abiotic/biotic feedback and it can also be used to address other causes for regime shifts other than the changes in salinity and nutrient inflow, which have caused the changes in Ringkøbing Fjord. The model has previously been tested for more than 20 smaller coastal areas and was shown to predict variations in foodweb characteristics very well. The focus of this paper is on temporal variations within one well-studied coastal area. The paper compares modeled values to empirical data for Ringkøbing Fjord and discusses fundamental ecosystem features such as regime shifts and compensatory effects in a way that is not practically feasible without the use of quantitative models.
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References
Arai MN (2001) Pelagic coelenterates and eutrophication: a review. Hydrobiologia 451:69–87
Boston HL, Adams MS, Madsen JD (1989) Photosynthetic strategies and productivity in aquatic systems. Aquat Bot 34:27–57
Busch W-DN, Sly PG (1992) The development of an aquatic habitat classification system for lakes. CRC Press, Boca Raton
Chapra SC (1980) Application of the phosphorus loading concept to the Great Lakes. In: Loehr C, Martin CS, Rast W (eds) Phosphorus management strategies for lakes. Ann Arbor Science Publishers, Ann Arbor, pp 135–152
Dillon PJ, Rigler FH (1974) The phosphorus–chlorophyll relationship in lakes. Limnol Oceanogr 19:767–773
Dodds WK (2003) Misuse of inorganic N and soluble reactive P concentrations to indicate nutrient status of surface waters. J North Am Benthol Soc 22:171–181
Evans MS, Arts MT, Robarts RD (1996) Algal productivity, algal biomass, and zooplankton biomass in a phosphorus-rich, saline lake: deviations from regression model predictions. Can J Fish Aquat Sci 53:1048–1060
Fleming RH (1939) The control of diatom populations by grazing. J Cons Perm Explor Mer 14:210–227
Guildford SJ, Hecky RE (2000) Total nitrogen, total phosphorus, and nutrient limitation in lakes and oceans: Is there a common relationship? Limnol Oceanogr 45:1213–1223
Håkanson L (1999) Water pollution—methods and criteria to rank, model and remediate chemical threats to aquatic ecosystems. Backhuys Publishers, Leiden, p 299
Håkanson L (2006) Suspended particulate matter in lakes, rivers and marine systems. The Blackburn Press, New Jersey, p 331
Håkanson L, Boulion V (2002) The lake foodweb—modeling predation and abiotic/biotic interactions. Backhuys Publishers, Leiden, p 344
Håkanson L, Bryhn AC (2006) Goals and remedial strategies for water quality and wildlife management in a coastal lagoon—a case-study of Ringkøbing Fjord, Denmark. J Environ Manage (in press)
Håkanson L, Eklund JM (2007) A dynamic mass balance model for phosphorus fluxes and concentrations in coastal areas. Ecol Res 22:296–320
Håkanson L, Gyllenhammar A (2005) Setting fish quotas based on holistic ecosystem modeling including environmental factors and foodweb interactions—a new approach. Aquat Ecol 39:325–351
Håkanson L, Lindgren D (2006) CoastWeb, a foodweb model based on functional groups for coastal areas including a mass-balance model for phosphorus. Manuscript, Uppsala University
Håkanson L, Peters RH (1995) Predictive limnology. Methods for predictive modeling. SPB Academic Publishing, Amsterdam, p 464
Håkanson L, Bryhn AC, Eklund JM (2006a) Modeling phosphorus and suspended particulate matter in Ringkøbing Fjord in order to understand regime shifts. J Mar Syst (in press)
Håkanson L, Bryhn AC, Blenckner T (2006b) Operational effect variables and functional ecosystem classifications—a review on empirical models for aquatic systems along a salinity gradient. Int Rev Hydrobiol (in press)
Harvey CJ, Cox SP, Essington TE, Hansson S, Kitchell JF (2003) An ecosystem model of food web and fisheries interactions in the Baltic Sea. ICES J Mar Sci 60:939–950
Hobbie JE (1988) A comparison of the ecology of planktonic bacteria in fresh and salt water. Limnol Oceanogr 33:750–764
Josefson AB, Hansen JLS (2004) Species richness of benthic macrofauna in Danish estuaries and coastal areas. Global Ecol Biogeogr 13:273–288
Kiørboe T (1980) Distribution and production of submerged macrophytes in Tipper Grund (Ringkøbing Fjord, Denmark), and the impact of waterfowl grazing. J Appl Ecol 17:675–687
King GM, Garey MA (1999) Ferric iron reduction by bacteria associated with the roots of freshwater and marine macrophytes. Appl Environ Microbiol 65:4393–4398
Kranck K (1973) Flocculation of suspended sediment in the sea. Nature 246:348–350
Kranck K (1979) Particle matter grain-size characteristics and flocculation in a partially mixed estuary. Sedimentology 28:107–114
Lehman JT (1988) Ecological principles affecting community structure and secondary production by zooplankton in marine and freshwater environments. Limnol Oceanogr 33:931–945
Lopez GR (1988) Comparative ecology of the macrofauna of freshwater and marine muds. Limnol Oceanogr 33:946–962
Maitland PS (1978) Biology of fresh waters. Blackie, Glasgow, p 244
Maitland P, Linsell PS (1977) The Hamlyn guide to the freshwater fishes of Britain and Europe. The Hamlyn Publishing Group Ltd., Feltham, p 256
Meeuwig JJ, Kauppila P, Pitkänen H (2000) Predicting coastal eutrophication in the Baltic: a limnological approach. Can J Fish Aquat Sci 57:844–855
Menshutkin VV (1971) Mathematical modeling of populations and communities of aquatic animals (in Russian). Leningrad
Mills CE (2001) Jellyfish blooms: are populations increasing globally in response to changing ocean conditions? Hydrobiologia 451:55–68
Monte L (1995) A simple formula to predict approximate initial contamination of lake water following a pulse deposition of radionuclide. Health Physics 68:3
Monte L (1996) Collective models in environmental science. Sci Tot Environ 192:41–47
Northcote TG (1978) Migratory strategies and production in freshwater fishes. In: Gerking SD (ed) Ecology of freshwater fish production. Blackwell, Oxford, pp 326–359
Odum E (1986) Ecology (in Russian). Moscow
OAECD (1982) Eutrophication of waters. Monitoring, assessment and control. OECD, Paris, p 154
Peters RH (1991) A critique for ecology. Cambridge University Press, Cambridge, p 366
Remane A (1934) Die Brackwasserfauna. Verh Dt Zool Ges 36:34–74
Riley ET, Prepas EE (1985) Comparison of the phosphorus-chlorophyll relationships in mixed and stratified lakes. Can J Fish Aquat Sci 42:831–835
Rout NP, Shaw BP (1998) Salinity tolerance in aquatic macrophytes: probable role of proline, the enzymes involved in its synthesis and C4 type of metabolism. Plant Sci 136:121–130
Rout NP, Shaw BP (2001) Salt tolerance in aquatic macrophytes: possible involvement of the antioxidative enzymes. Plant Sci 160:415–423
Sandberg J, Elmgren R, Wulff F (2000) Carbon flows in Baltic Sea food webs—a re-evaluation using a mass balance approach. J Mar Syst 25:249–260
Smith VH (1979) Nutrient dependence of primary productivity in lakes. Limnol Oceanogr 24:1051–1064
Tonn WM, Magnusson JJ, Rask M, Toivonen J (1990) Intercontinental comparison of small-scale fish assemblages. The balance between local and regional processes. Am Nat 136:345–375
Vollenweider RA (1968) The scientific basis of lake eutrophication, with particular reference to phosphorus and nitrogen as eutrophication factors. Tech. Rep. DAS/DSI/68.27, OECD, Paris, p 159
Walters CJ, Christersen V, Pauly D (1997) Structuring dynamic models of exploited ecosystems from trophic mass-balance assessments. Rev Fish Biol Fish 7:139–172
Walters CJ, Christersen V, Pauly D, Kitchell JF (2000) Representing density dependent consequences of life history strategies in aquatic ecosystems: Ecosim II. Ecosystems 3:70–83
Winberg GG (1985) Main features of production process in the Naroch lakes. Ecological system of Naroch lakes (in Russian). Minsk, pp 269–284
Acknowledgments
This work was carried out within the framework of the Thresholds project, and integrated EU project (no. 003933-2), and we would like to acknowledge the financial support from EU and the constructive cooperation within the project. Special thanks to Prof. Carlos Duarte, the scientific coordinator of the Thresholds project and to Jens W. Hansen for support concerning data and knowledge regarding Ringkøbing Fjord.
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Håkanson, L., Bryhn, A.C. Modeling the foodweb in coastal areas: a case study of Ringkøbing Fjord, Denmark. Ecol Res 23, 421–444 (2008). https://doi.org/10.1007/s11284-007-0395-7
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DOI: https://doi.org/10.1007/s11284-007-0395-7