Analysis of the influence of environmental change on river runoff in Loess Plateau of China

摘要

The double interaction between climate change and human activity affects the changes in the environmental conditions of catchment runoff and confluence. Using 1956-2012 57 years of river runoff series data of 27 rivers in hilly gully area of Loess Plateau in Shaanxi province 39 hydrological station data, reduction of social and economic water consumption, plotting the annual precipitation and annual runoff double cumulative curve of annual runoff flow series consistency test, the consistency processing of annual runoff data and the quantitative analysis of its influence were also made. The results show that: the consistency of annual runoff data sequence of 21 hydrological stations is affected by the change of environmental conditions of runoff generation and confluence, and the turning point (year) and the degree of impact can be divided into three situations or three periods. One is the 12 station in 2000 after the annual runoff system is small; Two, there are 4 stations before and after in 1970, the annual precipitation and annual runoff double cumulative curve is obviously turning point. Before the turning point, a series of systems has a large high production period. After turning, it shows that a series of systems with low runoff yield caused by the Changes in environmental conditions of runoff and confluence in the underlying surface and climate and so on; the three is to have 5 stations occurred both before and after the 1970 high low flow period of the transition period in 2000, and after the annual runoff series of small low again.