青海湖流域50年来(1956-2007年)河川径流量变化趋势——以布哈河和沙柳河为例

Trend of streamflow in Lake Qinghai basin during the past 50 years(1956-2007)——Take Buha River and Shaliu River for examples

通过对青海湖流域布哈河和沙柳河50年来的河川径流量分析发现,布哈河和沙柳河年径流量50年来没有显著的变化趋势,这两条河流的河川径流量对青海湖水位下降所起的作用不明显;布哈河月平均流量的年际变化在1月、2月和3月有减少的趋势,沙柳河月平均流量的年际变化在1月、2月、4月和5月亦有减少的趋势;布哈河的径流量大于沙柳河的径流量,在55%-91%频率范围内,布哈河的径流量小于沙柳河的径流量,在其它频率范围内,布哈河的径流量显著大于沙柳河的径流量,在一年中,布哈河和沙柳河的月径流量具有显著的差异;布哈河来水丰沛期是20世纪60年代,贫乏期是90年代,70和80年代为平水期;沙柳河月径流量从20世纪60年代到90年代一直比较稳定,没有发生显著的变化.

Annual streamflow of Buha River and Shaliu River were studied in this paper.No significant changes were found during the past 50 years,which indicated that the decline of the water level of Lake Qinghai was not affected by the streamflow of the two rivers in Lake Qinghai basin.The monthly mean streamflow of Buha River had declined trend in January,February and March,and the monthly mean streamflow of Shaliu River also had declined trend in January,February,April and May.The yearly streamflow of Buha River was larger than Shaliu River,but the streamflow of Shaliu River was larger than Buha River within the range of from 55%-91%.The monthly steamflow of Buha River and Shaliu River were of great difference.High flow period of Buha River were found in the 1960s,normal flow period in the 1970s and 1980s,while low flow period in the 1990s.Compared with Buha River,the streamflow of Shaliu River was steady.