河口镇--龙门区间降雨径流关系变化的原因

对黄河河口镇—龙门区间20世纪70年代以来降雨径流关系变化的原因进行了分析，认为当中雨、小雨时。水土保持作用可能对入黄径流量的减小起一定作用，但当遭遇大雨、暴雨时，则水土保持的作用将很小或不起作用。而近期河口镇—龙门区间大雨出现几率较前期减小26．2％，暴雨出现几率较前期减小53．7％，因此近期径流量减小的原因，不应单纯是水土保持作用的影响，降雨量的变化是主要原因，故在进行降雨径流关系“一致性处理”时需要进行深入研究。

Reasons for Variations of Rainfall - Runoff Relationship of Hekouzhen - Longmen Reach

The paper analyzes the causation of variations of rainfall-runoff relationship of Hekouzhen-Longmen reach of the Yellow River since 1970's and deems that soil and water conservation can play a certain action on reducing the runoff flowing into the river when it is moderate rain or light rain;the function of soil and water conservation will be very small or no function if it is heavy rain or storm.The probability of heavy rain happening in Hekouzhen-Longmen reach in the near future is 26.2% less than that of in the previous period and the storm 53.7% less.Therefore,the reasons of runoff reduction in the near future should not be simply the influence of soil and water conservation and the variation of precipitation is the main one.Thus,it needs a further study on "consistency treatment" of rainfall-runoff relationship.