2000年以来鄱阳湖枯水期进出湖流量增加及原因分析

The increase of average inflow and outflow rate in Poyang Lake during the dry season since 2000 and the reason analysis

2000年以来（2000~2012年）鄱阳湖流域平均降水量比多年（1953~2012年）平均值少2.61%,入湖、出湖平均流量分别少3.46%和1.76%,平水偏枯.但是2000年以后入湖、出湖枯水期平均流量比2000年以前（1953~1999年）分别多4.39%和8.02%.除了降水原因外,主要是森林覆盖率提高、土壤持水能力增强、改变了年内径流过程分配,以及中小型水库除险加固后发挥了更大的蓄丰补枯作用.

From 2000 to 2012, the average rainfall in Poyang lake is less than the average rainfall from 1953 to 2012 2.61%, the lake average inflow and outflow rate reduced by 3.46% and by 1.76%respectively, and the amount of water in average water sea- son tend to be low than before. However, compared with the water rate from 1953 to 2000, the lake average inflow and outflow rate in the dry season since 2000 increased by 4.39% and by 8.02% respectively. In addition to precipitation increase, main rea- sons are as follows： the increase of forest coverage rate, the enhancement of soil water-holding capacity, and the reinforcement of small and medium-sized reservoirs.