Experimental Researches On Eutrophication Of Reservoir Water On The Outskirts Of Chongqing

This article discusses the correlativity between parameters of eutrophication and several environment factors during the course of eutrophication in reservior waterbody on the outskirts of Chongqing. Outdoor simulated test was taken to simulate the eutrophication of waterbody. Day-to-day monitoring and hourly monitoring was done. The parameters include chlorophyll-a, ratio of nitrogen to phosphorous, dissolved oxygen and other environmental factors. The reaults indicate that the correlativity between parameters of eutrophication and several environment factors is distinct. â‘ The growth rate of chlorophyll-a increases first, and then declines when the algae grow normally.The curve of concentration of chlorophyll-a is the same as the logistic curve.According to the results of outdoor simulated test under different concentration of nitrogen and phosphorus, algae grow fastest when the ratio of nitrogen to phosphorous is 10:1~15:1. But the algae stop growing and then die out when the concentration of phosphorus reaches 5.775mg/l suddenly. â‘¡The correlativity between chlorophyll-a and light intensity, air temperature, water temperature is not distinct when algae grow normally and the parameters vary within the range of suited condition. â‘¢T he algae grow normally in pool 1, pool 2, pool 3 and pool 4. There is positive correlation between dissolved oxygen saturability and chlorophyll-a.Chlorophyll-a and pH has also the same correlation.Dissolved oxygen saturability and chlorophyll-a has also positive correlation.The correlativity is respectively 0.947,0.924,0.978. Dissolved oxygen saturability, pH value and chlorophyll-a of each pool have the same trend. â‘£The hourly monitoring performs some content following. The variation of dissolved oxygen saturability is the same as the variation of pH.The algae grow in pool 1, pool 2, pool 3, pool 4 and pool 5. The hourly correlativity between dissolved oxygen saturability and light intensity, air temperature, water temperature is respectively 0.411, 0.830, 0.834. The hourly correlativity between pH and light intensity, air temperature, water temperature is respectively 0.405, 0.829, 0.825.