黄河河口镇—龙门区间近期水沙变化特点分析

Variation Features of Runoff and Sediment in Hekouzhen—Longmen Reach of the Yellow River During 2000—2010

介绍了黄河河口镇—龙门区间的概况,利用实测资料对2000—2010年该区间的水沙特点进行了分析。结果表明:①与1956—1999年平均相比,2000—2010年多年平均降水量变化不大,但主汛期降水量偏小13%,较大降水量发生天数减少,小降水量发生天数增多,降水强度明显减弱;②8月水、沙量减少最多,分别占年减少量的32%、46%;③主汛期降水量减幅小于径流量的,径流量减幅小于输沙量的;④主汛期降水量与实测水、沙量的关系均发生了变化,与1969年以前相比,2000年以后降水量增大,径流量变化不大,而实测径流量相同的条件下输沙量明显减少。

This paper introduced the water and sediment situation in Hekouzhen-Longmen reach of the Yellow River. The variation of runoff and sediment of this reach was analyzed based on the measured data in 2000 -2010. The following conclusions have been drawn： a） In contrast with the multi-year average precipitation, the amount of precipitation in 2000 -2010 is little difference. However, the precipitation in main flood season reduces by 13%. The occurrence frequency of large precipitation decreases and small precipitation increases. The precipitation intensity falls down. b） The damping of runoff and sediment in August is the highest, which accounts for 32% and 46% of the annual reduction, c） The ascending sort of the reduction in main flood season is precipitation, runoff and sediment, d） The function relationship between the precipitation and runoff and sediment has changed. Compared with that before 1969, the runoff has little changes though the precipitation increases after 2000. And under the same runoff condition, the sediment amount has an obvious decrease.