| Abstract: | The effects of fish kill and different fish stocks on the phytoplankton and zooplankton dynamics were studied in a shallow hypertrophic reservoir system. When fish stock was below 100 kg ha−1, nutrient availability was not the main limiting factor for growth of phytoplankton. Consequently top‐down forces controlled phytoplankton. In the years with high fish stock (>100 kg ha−1) the bottom‐up forces dominated as nutrient availability was the main limiting factor for growth of phytoplankton. We can conclude that significant water quality improvement can be achieved in the reservoir system by decreasing fish stock below 100 kg ha−1. Although clear‐water phase could be stabilised temporary by macrophytes, stabilisation of good water quality requires continuous regulation of fish community. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) |
