三峡水库对长江N、P营养盐截留效应的模型分析

Analysis of the Three-Gorge Reservoir Impacts on the Retention of N and P in the Yangtze River

在长江流域干支流NP营养盐现场观测资料的基础上利用模式分析的方法分析了三峡水库对上游营养盐的截流效应. 三峡水库投入使用后发育出的水库生态系统可将上游输入的2%-7%溶解态无机氮和13%-42%的溶解态无机磷固定于浮游生物中库区水体中生物有机碳总量可保持在0.84109-2.65109mol的范围. 相应地三峡工程可减缓长江下游及长江口区的富营养化趋势但却在一定程度上加剧了长江中下游营养盐N/P比上升的趋势.

On the basis of in-situ nutrients (e.g. N, P) data conveyed in the main channel and tributaries of the Yangtze River, the Three-Gorge Reservoir retention effects on nutrients upstream have been analyzed by a simple model. The model outputs show that the Three-Gorge Reservoir ecosystem would fix 2%-7% dissolved inorganic N and 13%-42% dissolved inorganic P from the upstream, and that the amount of biogenic organic C in the reservoir water would reach 0.84109-2.65109mol. Consequently, the Three-Gorges Reservoir Project would slow down the eutrophication tendency of nutrients in the main channel downstream, while increase N/P ratio in the lower reaches of the Yangtze River to some extent.