调水对巢湖浮游植物群落演替模式的影响

建立了巢湖生态动力学模型CAEDYM,并利用2010年的实测出入湖流量、水质、水文、气象等数据对模型进行了参数验证,确定了适用于巢湖水环境特征的生态动力学模型参数.利用模型中的磷循环原理模拟了巢湖水体中磷的生态动力学循环过程和浮游植物群落的季节性演替模式,并模拟了调水对浮游植物群落演替模式的影响.模拟结果表明,巢湖浮游植物优势种的演替模式为:春季绿藻占优势,夏季和秋季蓝藻占优势,冬季硅藻占优势.通过夏季的短期调水可使巢湖各点最终的TN、TP分别平均下降了约18.9%,25.2%.从Chl a的计算结果可知,调水的实施对巢湖西半湖和中部湖区Chl a的改善效果比较明显,可使Chl a的峰值从69μg/L下降到57μg/L,对巢湖的蓝藻有较好的改善效果,且对浮游植物群落的季节性演替影响不大.

Influence of water transfer on the phytoplankton community succession mode in the Chaohu Lake

By establishing the ecosystem dynamics model CAEDYM of Chaohu Lake, and using the observation values of the flow that inflows and outflows the lake as well as the figures of the water quality, hydrology, meteorology, etc. in 2010 to verify the model’s parameter, the ecosystem dynamics model parameters fit for the environmental characteristics of the Chaohu Lake have been determined. The principle of the phosphorus cycle in the model was used to simulate the ecological dynamics cycle of phosphorus, the seasonal succession mode of phytoplankton communities and the influence of water transfer on the phytoplankton community succession mode in the Chaohu Lake. Simulation results show that the succession mode of dominant phytoplankton species in the Chaohu Lake is: chlorophyta dominate in spring, cyanobacteria dominate in summer and autumn, and bacillariophyta dominate in winter. Through the short water transfer in summer, the final TN, and TP in Chaohu spots has got an average decrease of 18.9% and 25.2%, respectively. From Ch1 a calculation, the enforcement of water transfer has apparent effect on improving the west and middle part of the lake, causing a decrease of Ch1 a from its max 69μg/L down to 57μg/L, effectively improving the state of cyanobacteria in Chaohu while showing little effect on the seasonal succession mode of phytoplankton community.