Objetivo Problems to be solvedDeterioration of water quality of freshwater lakes, as a consequence of man-made perturbations such as water level regulations, pollution and food web manipulations is a commonly observed phenomenon of our times. In the extreme case of long lasting elevated pollution loads and the affluence of bio-available phosphorus (BAP) the lake ecosystem responded with increasing algal biomass and a species shift to nitrogen fixing cyan bacteria. After becoming aware of phosphorus (P) as the driving force of eutrophication the reduction of external P loading became the primary management target. However, in many cases even a drastic reduction of the external P-loading did not succeed in improving water quality since P-recycling from bottom sediments sufficed to provide the amount of BAP necessary to support algae blooms. The question arises in how far this development can be reversed and algae diversity restored. Considering the variety of available remedial measures, an experimental procedure to predict water quality changes is needed to arrive at the decision upon the optimum management strategy. The proposed study complies with this requirement through an experimental approach based upon the control of environmental parameters such as nutrient loading or resuspension in large enclosures, while monitoring phytoplankton succession. Our proposal enforces community water policy aimed to achieve sustainability of aquatic systems by responding to the following Water Framework Directives: eutrophication control (91/271/EEC) and safeguarding human health by establishing strict standards for the quality of water intended for human consumption (80/778/EEC).Scientific objectives and approachUsing a novel monitoring tool for phytoplankton diversity and biomass the present study is aimed at the interactive regulation of phytoplankton succession by physical forcing and internal P loading in freshwater lakes.Our work plan is designed to arrive at these goals by meeting the following objectives:· Introduction of delayed fluorescence spectrometry (DF) as a tool for continuous on-line monitoring of phytoplankton density composition and activity in aquatic systems.· Quantification of internal P loading due to sedimentary P release, by following P accumulation into the water column of large limnocorrals.· Studying the dynamics between the dissolved phase and the particulate phase of P within the enclosures with special emphasis on resuspension and sedimentation processes.· Investigation of the phytoplankton response to different internal P loading scenarios as simulated in the limnocorrals· In case of cyanophyta blooms: Assessment of the contribution of benthic recruitment of cyanobacteria to internal P loading by measuring changes in cyan bacterial filaments and intracellular stored phosphorus using conventional counting techniques together with a novel HPLC approach.· Under collaboration between the three modelling groups involved in this study we intend to create an overall modelling framework where the fluxes of phosphorus (total, dissolved and particulate P) and their spatio-temporal dynamics are accounted for in both the sediment and water-column.Expected ImpactsThe method presented in this study is expected to have revolutionary impact on the formulation of ecological quality targets and ecosystem management according to EC guidelines. The quantification of the response of phytoplankton to changing internal P-loading scenarios is a key objective of this study. By studying lakes in different climatic zones and different types of internal P loading using the same monitoring strategies we intend to elucidate the relationship between algae diversity and the physical and biogeochemical control parameters and as such to refine the present knowledge on one of the key process within aquatic ecosystems (RTD priority 1.2.1). By simulating different loading scenarios we intent to quantify the critical loading reduction needed to arrive at the intended change in algal diversity. The result is expected to optimise remedial measures aimed at phytoplankton diversity as an ecological quality target (RTD priority 1.2.2). Ámbito científico natural sciencesearth and related environmental sciencesatmospheric sciencesclimatologyclimatic zonesnatural sciencesbiological sciencesmicrobiologyphycologynatural sciencesearth and related environmental sciencesenvironmental sciencespollutionnatural sciencesbiological sciencesecologyecosystemsnatural sciencesearth and related environmental scienceshydrologylimnology Programa(s) FP5-EESD - Programme for research, technological development and demonstration on "Energy, environment and sustainable development, 1998-2002" Tema(s) 1.1.4.-1. - Key action Sustainable Management and Quality of Water Convocatoria de propuestas Data not available Régimen de financiación CSC - Cost-sharing contracts Coordinador ISRAEL OCEANOGRAPHIC & LIMNOLOGICAL RESEARCH INSTITUTE Aportación de la UE Sin datos Dirección Tel Shikmona 31080 HAIFA Israel Ver en el mapa Coste total Sin datos Participantes (5) Ordenar alfabéticamente Ordenar por aportación de la UE Ampliar todo Contraer todo BUDAPEST UNIVERSITY OF TECHNOLOGY AND ECONOMICS Hungría Aportación de la UE Sin datos Dirección Muegyetem rkp 3 1518 BUDAPEST Ver en el mapa Coste total Sin datos TEL AVIV UNIVERSITY Israel Aportación de la UE Sin datos Dirección Ramat Aviv 69978 RAMAT - AVIV Ver en el mapa Coste total Sin datos UNIVERSITAET REGENSBURG Alemania Aportación de la UE Sin datos Dirección 31,Universitätstrasse 31 93040 Regensburg Ver en el mapa Coste total Sin datos UNIVERSITY OF VESZPREM Hungría Aportación de la UE Sin datos Dirección Egyetem u. 10 8201 VESZPREM Ver en el mapa Coste total Sin datos UPPSALA UNIVERSITY Suecia Aportación de la UE Sin datos Dirección 18B,Norbyvaegen 18B 752 36 UPPSALA Ver en el mapa Coste total Sin datos
