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利用近50 a的实测数据,分析了泾河流域的径流时空变化规律和主要驱动因子。研究表明:年降水量和径流深的空间分布均呈现从南到北的明显减少趋势,并在上游山区出现高值区。流域径流总量自20世纪60年代到21世纪初显著减少,由50.1 mm减到22.3 mm,但各区域的变化很不均匀,其中西部、西南和东南的子流域径流大量减少,可达17.5 mm/10 a;北部和东北则减少不明显,最大减少率仅为1.3 mm/10 a。降水量变化曾是径流减少的重要原因,但20世纪90年代后实施的退耕还林等生态工程在2000年后已经成为引起径流减少的最主要原因。
Using the measured data of nearly 50 years, the temporal and spatial variation of runoff in Jinghe River Basin and its main driving factors were analyzed. The results show that the spatial distribution of annual precipitation and runoff depth are obviously decreasing from south to north, and there are high value areas in the upstream mountainous areas. The total amount of runoff in the basin dropped significantly from 50.1 mm to 22.3 mm from the 1960s to the beginning of the 21st century, but the variation in the areas was very uneven. The runoff in the sub-basins in the west, southwest and southeast decreased greatly, reaching 17.5 mm / 10 a; the decrease in the north and northeast is not obvious, the maximum rate of decrease is only 1.3 mm / 10 a. The change of precipitation has been the important reason for the decrease of runoff. However, the ecological engineering such as returning land for farming to forestry after the 1990s has become the most important cause of the runoff reduction after 2000.