无定河年径流量变化特征及人为驱动力分析

THE ANALYSIS ON THE CHANGE CHARACTERISTICS AND DRIVING FORCES OF WUDINGHE RIVER RUNOFF

分析无定河年径流量1956—2000年时间序列变化特征及其对气候因子的敏感程度,以径流突变前的数据建立预测模型;对比分析径流量的实测值与模型输出值,其差值即人为影响程度。结果表明无定河年径流总量显著减少,径流量演变以1971年为突变点分为前后2个阶段;人为因素驱动力占总驱动力的份量显著上升,1997年达到最大值,为56.9%。可以认为在全球变化的气候背景下,人类活动因子是无定河径流演变的主要驱动因子。

In this paper, the characteristics of annual runoff data of Wudinghe river in the year of 1956～2000 are the sensitive degree of influence from climate factors in the drainage area are analyzed. Based on the datum before abrupt change of annual runoff, the plural linear regression model for annual runoff is set up. The difference between the value derived by the function and the true value is the influence resulted by human activity.The analysis shows that the annual runoff of Wudinghe river decreased evidently, and the runoff changed abruptly in 1971. The influence resulted by human activity is increasing year by year. And in the year of 1997, human influence on river runoff reached maximum, with its value being 56.9%. So the conclusion is reached that in the climate background of global warming the driving force of the change in annual runoff is human activity.