南水北调中线工程对汉江水华影响研究

汉江中下游近年来出现水华的根本原因是汉江下游水体污染严重,氮、磷等污染物浓度过高,春季光照充足、水温升高,汉江枯水时长江水位偏高导致汉江流速变缓。在污染负荷保持现状的前提下,建立水动力学模型和富营养化模型,并通过在诱发水华的各环境因子样本集合中抽样组合,计算南水北调中线工程调水前与调水后的水华发生概率。结果表明,调水145亿m3后汉江水华发生的概率将会增加,而引江济汉工程的兴建能有效控制水华的发生。

Influence of the water transfer project from south to north(middle route) on algalbloom in Hanjiang River

The basic reasons of algalbloom occurrence in middle and lower reaches of Hanjiang River are terrible pollution of water in lower reaches,sun light and rising water temperature in spring,and the slow velocity of flow in Hanjiang River as the result of low water in Hanjiang River as well as relatively high water level in Yangtze River.A hydrodynamics model and eutrophication model are established,providing pollution load maintains the status quo.By sampling in each aggregate of environmental factor which conduces toal-galbloom,the probability of algalbloom occurrence around transfering water are calculated by using the models.The result indicates that the probability will be increased after transferring 14.15 billion m³ water from Hanjiang River,but decreased after finishing of the water transfer project from Yangtze River to Hanjiang River.