摘要
The hypertrophic subtropic Donghu Lake’s dense water bloom(of mainly Microcystis Anaabaena andOscillatoria)that occurred annually from the beginning of the 1970s, has disappeared since 1985. The infiuenceof planktivorous fishes (silver and bighead carps) on the water bloom was studied for three years usingthe enclosure method. The enclosures stocked densely with bighead and/or silver carp were free of waterbloom during the experimental period. The water bloom that appeared in the fish-free enclosures was completelyeliminated in 10-20 days by introduction of silver and/or bighead carp(grass carp was not effectivein controlling water bloom).This study showed clearly that grazing pressure by planktivorous fishes is a keyfactor in eliminating water bloom from the lake.
The hypertrophic subtropic Donghu Lake's dense water bloom (of mainly Microcystis, Anabaena and Oscllatoria)that occurred annually from the beginning of the 1970s, has disappeared since 1985. The influence of planktivorous fishes (silver and bighead carps) on the water bloom was studied for three years using the enclosure method. The enclosures stocked densely with bighead and/or silver carp were free of water bloom during the experimental period. The water bloom that appeared in the fish-free enclosures was completely eliminated in 10-20 days by introduction of silver and/or bighead carp(grass carp was not effective in controlling water bloom).This study showed dearly that grazing pressure by planktivorous fishes is a key factor in eliminating water bloom from the lake.
基金
This work was supported by FEBL(State Key Laboratory for Freshwater Ecology and Biotechnology of China)funds
National Natural Science Foundation of China (Grant NO.3937014)
