Recent sedimentation rates of Poyang Lake

Abstract

由于受到长江和入湖河流双重影响,鄱阳湖沉积可分为南部三角洲前缘、中部开阔湖和北部入江水道三个区域。按各区特点,采用了C.J.C.和C.R.S.不同计算模式,分别得出其沉积速率为0.52、0.16和0.34cm/a。湖区不同沉积地貌单元沉积速率的差异,受物源和水动力条件的影响:水下天然堤、漫滩、堤外洼地及开阔湖沉积速率分别为0.80、0.36、0.13和0.17cm/a。此外,三角洲的迅速伸长,河道分汊或改道,流域水土流失及大型水利工程等天然和人为活动也影响到沉积速率的时空变化。;The process of sediment accumulation in Poyang Lake is complex due to spatial and temporal changes in environmental conditions controlled both by inlet rivers and the Changjiang River.The whole lake can be divided into three different parts according to the characteristics of sedimentation processes,i.e.southern, middle and northern parts,the average rates of which are 0.52cm/a,0.16cm/a and 0.34cm/a,respectively.Moreover,the sedimentation rates in different sedimentary geomorphic units are varied with changes of water dynamics and material sources, g.0.80cm/a for levee,0.36cm/a for flood plain,0.13cm/a for small secondary depression and 0.17cm/a for open area.