三峡工程运行后长江中游溶解气体过饱和演变研究  

The Evolvement Study on Supersaturation of Dissolved Gas in the Middle Reaches of Yangtze River after the Three Gorges Project Running

作　　者：陈永柏[1,2] 彭期冬[3] 廖文根[3] 

机构地区：[1]中国科学院遥感应用研究所,北京100101 [2]中国长江三峡工程开发总公司,湖北宜昌443002 [3]中国水利水电科学研究院,北京100038

出　　处：《水生态学杂志》2009年第5期1-5,共5页Journal of Hydroecology

基　　金：水利部公益性行业科研专项(200701029);中国长江三峡工程开发总公司生态与环境保护科研项目(0799509)

摘　　要：为了分析三峡工程运行后泄洪对长江中游溶解气体过饱和的影响,建立了长江中游溶解氧数学模型,对不同流量下长江中游的溶解氧过饱和演变进行了模拟预测。模拟结果表明,三峡和葛洲坝过坝水流的溶解氧饱和度在流量40000～50000m3/s和100000m3/s附近存在2个峰值,长江中游河道天然情况下溶解氧过饱和恢复速度较为缓慢,平均每100km降低5%,洞庭湖水的汇入能显著降低长江干流的溶解氧过饱和度。当三峡出库流量超过40000m3/s时,其影响范围可达400km以上。讨论了溶解气体过饱和的不同指标间的关系,对气体过饱和可能造成的影响以及对长江中游鱼类目前的影响进行了阐述,认为通过三峡水库的调度减少出库高流量次数和历时是减缓下游溶解气体过饱和的有效手段。In order to analyze the ecological effects of gas supersaturation by the Three Gorges Dam in the middle reaches of Yangtze River, this paper established a mathematical model of dissolved oxygen （DO） in the middle reaches of the Yangtze River. Using this model, the evolvement of supersaturation of dissolved oxygen under different discharges in the middle reaches of the Yangtze River was simulated and predicted. The results showed that there were two peaks of DO, one of which was at the discharge between 40 000 m^3/s and 50 000 m^3/s, the other was near the discharge of 100 000 m^3/s. The reduction of DO was very slow in the natural river and the rate was 5% per 100 km in the middle reaches of Yangtze River. The inflow of Dongting Lake can reduce the supersaturation of DO in Yangtze River. When the outflow of Three Gorges Reservoir was 40 000 m^3/s, the harmful range was more than 400 kin. This paper also discussed the relationship among different indexes of gas supersaturation and briefly analyzed the effects of gas supersaturation on fishes in the middle reaches of Yangtze River. Reducing the times and duration of high outflow of Three Gorges Reservoir through the operation was considered the best mitigation measures.

关 键 词：三峡工程 长江中游 气体过饱和 演变 

分 类 号：X824[环境科学与工程—环境工程] X143