祖厉河河源区径流、泥沙对气候的响应研究

Study on the response of runoff and sediment to climate change in the Zuli River source area

针对黄河上游一级支流祖厉河的河源区河川径流及泥沙变化对气候的响应过程进行分析研究,运用水文统计学方法对30多年实际观测资料进行分析,结果表明:祖厉河上游源区的径流、泥沙对研究区的气候变化敏感。自20世纪80年代以来气温显著升高,蒸发量呈显著增加趋势,且两者变化速率高于黄河上游及全球变化速率,分别为0.75℃/10a和34.8 mm/10a。同时降水呈现减少趋势,河道径流和泥沙受气候变化影响显著减少,自2000年以来,祖厉河上游基本断流,1997年发生径流突变以及降水-径流、径流-泥沙关系的变化。而人类保护生态环境所采取的工程措施有效减少了土壤侵蚀,泥沙的突变时间有所延迟。

This study analyzed the response process of the river runoff and sediment to climate change in the source region of Zuli River,a first level tributary of the upper reaches of the Yellow River,using the hydrological and statistical methods based on the actual observational data for more than 30 years.The results showed that the runoff and sediment of this area were sensitive to the changes of the climate.Since the 1980 s,the temperature and evaporation increased significantly by the rates of 0.75℃/10 a and 34.8 mm/10 a,respectively,and the change rates were higher than those of the upper reaches of the Yellow River and the global rivers.In addition,the precipitation showed a decreasing trend,and accordingly the runoff and sediment decreased significantly.Since 2000,the upper reaches of the Zuli River had completely dried up,Moreover,an abrupt change of runoff occurred and the relationship between precipitation and runoff,runoff and sediment changed in 1977.It indicates that the engineering measures for the protection of environment and ecology have effectively alleviated the soil erosion and delayed the occurrence of sediment abrupt changes.