摘要： 分析了1970-2000年滹沱河的重要支流——冶河流域径流减少的主要驱动因子气候和地表覆被的变化趋势及其对流域径流的影响。结果表明,30年来,流域降水量减少,流域内的年平均气温上升并达到显著水平。流域1995年有林地和高覆盖草地所占面积同20世纪80年代相比大幅减少,林地和草地的质量有所下降,到了2000年有所回升;流域内农田的有效灌溉面积逐年增加。同时流域的径流量发生了明显变化:年均流量自1966年以来不断减小,尤其是80年代以后下降趋势更明显,以致上游长年有水河流部分河段出现了不同程度的断流。

关键词: 气候变化, 地表覆被变化, 径流减少

Abstract: The changes in hydrology in the Yehe catchment,an important branch of the Hutuo river,from climate fluctuation and land cover changes during 1971-2000 were analyzed.During this period,Yehe basin experienced decreases in annual precipitation and the annual temperature increased significantly,especially during the winter period from November to February in the following year.During the study period,the total change in area of each land use,including grass,forest,farmland(irrigated and non-irrigated) and others was not obvious.However in 1995,the forest and densely grass coverage dropped fast,the farmland area increased to a maximum of 29.75%.Over time,irrigation area of farmland gradually increased.For instance,irrigation area of Xiyang city was only 1 190 ha in 1990,but in 2000 it reached 3 109 ha.In the meantime,the hydrological system changed significantly.To 2000,the land coverage recovered in 1980.Annual streamflow decreased considerably and the downward trend was more significant than that of annual temperature and annual precipitation.Especially after the 1980s,the annual runoff decrease was serious and some of the upstream rivers dried up.

Key words: Climate fluctuation, Land cover change, Hydrological effect

中图分类号: 

• S162