Analysis of the Runoff and Sediment Development Distr ibution and Influencing Factor of Fenhe River dur ing the Last 50 Year s
1950 年以来汾河水沙演变规律及影响因素分析

Based on the hydrologic data from the Hejin station of Fenhe River since the 1950s,the seasonal and annual change of runoff and sediment was analyzed,and the influence of human activities on the runoff was estimated.The results show that the seasonal distribution of runoff and sediment was quite uneven,while there was obvious increase in the Cvy and the degree of stability became lower and lower.The annual distribution of runoff and sediment was different in great scope,annual runoff was rainless period since the 1980s.To analysis the trend of runoff and sediment change using the cumulative filter method,the results show that there was obvious decline,and the variation of sediment change was greater runoff change.Analyses of double mass curve of annual runoff and precipitation showed that the decline in the runoff occurred in 1964.On average,75.912% of total annual runoff reducition was induced by human activities.Human activities were main reasons of runoff reduction in Fenhe River basin.