赣江流域径流量和输沙量的变化过程及其对人类活动的响应

Variation of runoff and sediment discharge and response to human activities in the Ganjiang River

近年来频繁出现的鄱阳湖季节性干枯问题受到广泛关注,作为鄱阳湖水系五大河流之首的赣江入湖水沙量及其变化也同样受到重视。采用1962-2013年赣江控制站外洲水文站实测水沙及流域内降雨量资料,通过多种计量统计学方法,分析了赣江降雨量、径流量和输沙量变化特征,并评估了人类活动对径流量及输沙量的影响。结果表明,赣江流域面降雨量和径流量无明显变化趋势,输沙量呈显著的下降趋势,并经历了平沙期—丰沙期—平沙期—枯沙期4个阶段。输沙量突变年份为1984和1992年,以1962-1983年为参照期,1984-1991年人类活动使河流输沙量减少36.3%,1992-2013年则使输沙量减少88.1%,水土保持和水库建设是赣江年输沙量减少的主要因素。

The problems of seasonal dry in Poyang Lake frequently in recent years were attracted wide attention. As the longest river in Poyang Lake water system,the runoff and the sediment of Gan Jiang River are also being more attention. Based on the runoff and sediment data of Waizhou hydrological station and main weather station measured rainfall from 1962 to 2013,the characteristics of rainfall,runoff and sediment transport were analyzed by statistical methods,and the impact of human activities on runoff and sediment yield were assessed. Results showed that surface rainfall and runoff with a rising trend is not significant,but sediment transport were significantly decreased,and experienced four stage as periods of flat,high,flat,and low. The obvious change points of annual sediment load occurred in 1984 and 1992. Compared to 1962- 1983,human activities make sediment discharge decreased by 36. 3% from 1984 to 1991 and make sediment discharge decreased by 88. 1% from 1992 to 2013. Soil and water conservation and construction of reservoirs are the dominant factors to reduce annual sediment in the Ganjiang River basin.