Variation of Annual Streamflow and the Effect of Human Activity in the Kuye River during 1956 to 2005
Based on meteorological and hydrological data of the Kuye River on the Loess Plateau from 1956 to 2005,the paper studied the variation tendency,the abrupt and periodic changes of annual streamflow using the nonparametric test,R/S analysis,wavelet analysis and frequency analysis.The empirical equation which shows the relationship between rainfall and runoff was established to estimate the impact of human activities on the runoff variation.The results showed that the annual streamflow in the river basin declined markedly with 0.11 × 108 m3/a.The change points occurred in 1979 and 1996.The frequency analysis showed that,compared to period 1 from 1959 to 1979,the runoff reducing extent at 5％,50％ and 95％ in period 3 from 1997 to 2005 was greater than that in period 2 from 1980 to 1996.The main periods are 9 a,18 a and 32 a.Compared to period 1,the contribution rates of climate change and human activities were 58.62％ and 41.38％,respectively in period 2.In period 3,the contribution rate of human impact increased to 78.25％ of streamflow change,in which the impact of coal mining being 52.27％.The human activities were the main driving force for the decrease of runoff; however,the influence of climate change cannot be ignored.Their impacts should be taken into consideration when carrying out comprehensive improvement of soil and water conservation and rational use of water resource.
streamflow reductionclimate changehuman activityKuye River
NETL
NSTL
万方数据
