渭河源区水文气象要素演变趋势及阶段性分析

Evolutionary trend and stage analysis of hydrologic and meteorological elements in Weihe river source area

研究渭河源区水文气象要素变化特征,并进一步分析各个要素之间的相互关系,为渭河源区水资源的合理开发利用提供科学依据与技术支撑。采用坎德尔秩次相关、斯波曼秩次相关、线性趋势回归检验法对渭河源区水文气象要素变化趋势进行检验,利用M-K检验法找出各要素的突变年份,运用多元线性回归分析法分析不同阶段降雨、蒸发量对径流量的影响程度。结果表明:近30年来渭河源区年降水量与四季降水量均呈不显著减少趋势,年蒸发量与春、夏季蒸发量呈显著增加趋势,年径流量与夏季径流量呈显著减少趋势,冬季径流量呈不显著增加趋势。年降水量和年径流量均在1993年发生显著性突变,年蒸发量在1990年发生显著性突变。分析得出:1981-1993年年径流量变化主要受降水量变化影响,1994-2010年径流量变化主要受蒸发量变化影响。

This paper mainly studies the variation characteristics of hydrologic and meteorological elements in the Weihe river source area, and further analyzes the relationship between the various elements.The variation trend of hydrologic and meteorological elements in the Weihe river source area was tested by using the Handel rank correlation, Barmen rank correlation, and linear trend regression test.The mutation year was found out by using the M-K test, and the influence degree of rainfall and evaporation on the runoff in the different stages was analyzed by using multiple linear regression analysis.In the past 30 years, the annual precipitation and seasonal precipitation did not show a significant decreasing trend;and the annual evaporation and the evaporation in spring and summer showed a significant increasing trend;annual runoff and the runoff in summer showed a significant decreasing trend;the runoff in winter did not show a significant increasing trend.Annual precipitation and annual runoff occurred significant mutations in 1993, and annual evaporation occurred significant mutations in 1990.The annual runoff change is mainly affected by the change of precipitation from 1981 to 1993, and the change of annual runoff is mainly affected by the change of evaporation from 1994 to 2010.