Abstract
The aim of the study was to assess the effect of nutrient loading and water level regulation of water quality in Lake Võrtsjärv. The lake is highly eutrophic and it has a high value for fisheries and recreation. A water quality model was developed in order to make predictions of the effects of the different possible restoration measures (reduction of nutrient loading, water level regulation) planned to be carried out. Two phytoplankton groups, diatoms and cyanobacteria, were included in the model. Their contribution to the total algal biomass is dominating. The other state variables of the model are concentration of soluble reactive phosphorus (SRP), concentration of inorganic nitrogen and concentration of dissolved oxygen. The ecological model was constructed using continuously stirred tank reactor (CSTR) hydraulics. The zero-dimensional approach could be used because the lake is shallow and has no thermal stratification. According to the model, external nutrient loading has a very small effect on the biomass of cyanobacteria, whereas the effect is clearer when diatoms are concerned. The contribution of water level to biomass is very significant for both diatoms and cyanobacteria.
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References
Bilaletdin, Ä., T. Frisk & T. Huttula, 1993. Roineen vedenottoalueen veden laadun riippuvuus lähivaluma-alueen kuormituksesta ja Längelmäveden vedenlaadusta. (The water quality of Lake Roine and its dependency on the load of from watershed and from Lake Längelmävesi). Vesi-ja ympäristöhallituksen monistesarja nro 512: 56 pp. (In Finnish).
Chapra, S. C., 1997. Surface water quality modeling. The McGraw-Hill Series in Water Resources and Environmental Engineering. Singapore: 844 pp.
Droop, M. R., 1974. The Nutrient Status of Algal Cells in Continous Culture. J. mar. biol. Ass. U.K. 54: 825–855.
Frisk, T., Ä. Bilaletdin, K. Kallio & M. Saura, 1997. Modelling the effects of climate change on lake eutrophication. Boreal Envir. Res. 2: 53–67.
Grasshoff, K., M. Erhardt & K. Kremling (eds), 1982. Methods of Seawater Analysis. ISBN (Verlag Chemie): 3–527 25998–8.
Huttula, T. & T. Nõges (eds), 1998. Present State and Future Fate of Lake Võrtsjärv. Results from Finnish-Estonian joint project in 1993–1997. The Finnish Environment 209, Tampere: 150 pp.
Järvet, A., 1997. Võrtsjärve reostuskoormuse pikaajaline dünaamika (Long-term changes of pollution load of Lake Võrtsjärv).-Kaasaegse ökoologia probleemid. Ajalised muutused Eesti eluslooduses ja keskkonnas. Eesti VII Ökoologiakonverentsi lühiartklid. Tartu, 08.-09. Mai, 1997, lk. 60–65, (Problems of contemporary ecology. Temporal changes in Estonian nature and environment. Short communications of Estonian VII Conference in Ecology. Tartu, May 08–09th, 1997, in Estonian).
Kettunen, J., 1981. Model for a eutrophic Finnish lake - a case study. Aqua fenn. 11: 49–54.
Laws, E. A. & M. S. Chalup, 1990. A Microalgal Growth Model. Limnol. Oceanogr. 35: 597–608.
Malve, O., T. Huttula & K. Lehtinen, 1991. Modelling of eutrophication and oxygen depletion in Lake Lappajärvi. In Wrobel, L. C. & C. A. Brebbia (eds), Water Pollution: Modelling, Measuring and Prediction. Computational Mechanics Publications, Southampton: 111–124.
Malve, O., P. Ekholm, T. Kirkkala, T. Huttula & K. Krogerus, 1994. Säkylän Pyhäjärven ravinnekuormitus ja rehevyystaso. (Nutrient load and trophic level of Lake Pyhäjärvi (Säkylä)). Publications of National Board of waters and the Environment. Series A 181. Helsinki: 108 pp. (In Finnish).
Nyholm, N., 1978. Amathematical model for growth of phytoplankton. Mitt. Int. Ver. Limnol. 21: 193–206.
Nõges, P. (ed.), 1998. Limnology of Lake Võrtsjärv (Estonia). Limnologica 28.1. G. Fischer Verlag, Jena: 128 pp.
Nõges, P., A. Järvet, L. Tuvikene & T. Nõges, 1998. The budgets of nitrogen and phosphorus in shallow eutrophic Lake Võrtsjärv (Estonia). Hydrobiologia 363: 219–227.
Park, R. A., R. V. O'Neill, J. A. Bloomfield, H. H. Shugart Jr., R. S. Boorth, R. A. Goldstein, J. B. Mankin, J. F. Komce, D. Scavia, M. S. Adams, L. S. Clesceri, E. M. Colon, E. H. Dettman, J. A. Hoopes, D. D. Huff, S. Katz, J. F. Kitchell, R. C. Kohberger, E. J. LaRow, D. C. McNaught, J. L. Peterson, J. E. Titus, P. R. Weiler, J. W. Wilkinson & G. S. Zahorcak, 1974. A generalized model for simulating lake ecosystems. Simulation 23: 33–50.
Reichert, P., 1998. AQUASIM 2.0-User Manual. Technical report. Swiss Federal Institute for Environmental Science and Technology (EAWAG), CH-8600 Dübendorf, Switzerland. Thingstad, T. F., 1998. A theoretical approach to structuring mechanisms in the pelagic food web. Hydrobiologia 363: 59–72.
Whitehead, P. G., A. Howard & C. Arulmani, 1997. Modelling algal growth and transport in rivers: a comparison of time series analysis, dynamic mass balance, and neural network techniques. Hydrobiologia 347: 39–46.
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Frisk, T., Bilaletdin, Ä., Kaipainen, H. et al. Modelling phytoplankton dynamics of the eutrophic Lake Võrtsjärv, Estonia. Hydrobiologia 414, 59–68 (1999). https://doi.org/10.1023/A:1003802912687
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DOI: https://doi.org/10.1023/A:1003802912687