黄河流域下垫面变化对径流量影响的讨论

20世纪90年代以来,黄河流域径流量连续偏小,目前人们对于偏小的主要原因认识不一。经过对河源地区降水量与径流量关系分析,以及对中游地区渭河、伊洛河、沁河2003年汛期径流量和汛期多年径流量的对比分析认为,径流量偏小应与降水量连续偏小、超过一定量级的暴雨次数偏少、气温的增高以及蒸发量增大等多种因素有关。这些气象因素的变化,主要受气候波动的影响,至于河源区下垫面的破坏、中游中小型水利水保工程等不应是黄河径流量变小的主要原因,因此对未来径流量不需要进行降水量与径流量关系的“一致性处理”。

Discussions on the Influence of Variations of Underlying Surface of the Yellow River Basin on Amount of Runoff

Since 1990's, the amount of runoff of the Yellow River basin is getting smaller continuously. At present, people have different understanding on the main reasons of the situation. After analyzing the relationship between the precipitation and amount of runoff in the river source area, contrasting and analyzing the amount of runoff in 2003 flood season and runoff of many years in flood season of the rivers of Weihe, Yiluo and Qinhe located on the middle reaches, the smaller amount of runoff should be related to the factors of continuous smaller precipitation, less storm events and increased temperature and evaporation. The variations of meteorological factor are mainly effected by climate fluctuation. As for the destruction of underlying surface in river source area, the medium and small-sized soil and water conservation projects constructed on the middle reaches should not he the main reasons. Thus, it is not necessary to take "consistency treatment" of rainfall and runoff relationship for future amount of runoff.