| The water pollution of Taihu Lake is characterized by the severity of eutrophication and high frequency of algae bloom. Many studies show that hydrological and meteorologic factors exert profound influence on the lake eutrophication and algae bloom, but more researches emphasize on static experiments in laboratory and value simulation. Associated with the sub-project of"973"program"Studies on the process of lake eutrophication and the mechanism of algae bloom", by the way of historical data analysis for many years, field monitoring and dynamic simulation experiments in laboratory, this paper discussed these contents:(1) Effects of water temperature on the eutrophication and algal growth in Taihu LakeIt is showed that with increase of water temperature, the total algal biomass and chlorophyll concentration increase logarithmically, the scale of Microcysitis which is the main species forming algae bloom also increases quickly. When the water temper- ature is between 26℃and 31℃, the total algal biomass attains to the largest value. So the water temperature above 25℃can be regarded as a parameter to forecast the algae bloom.(2) Effects of wind-speed on the eutrophication and algal growth in Taihu LakeIt is indicated that the intensity of wind forcing has high relationship with the se- diment resuspension, nutrients concentration and the vertical distribution of algal chlo- rophyllthe. The nutrients release from sediment resuspension under high wind-speed conditions and provide the nutrient for the algae continually. This wind condition is very good for the algal reproducing. Low wind-speed make the floating algae remain on the surface and don't cause algae to leave away from the water surface. This wind-speed condition is good for the algal remaining and accumulation. So in summer, the low wind-speed condition after high wind-speed can be regarded as an important parameter to forecast the algae bloom.
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