|
|
|
| Effects of soil and water conservation on reduction of runoff and sediment in Chabagou Watershed |
| Qi Junyu1,2,Cai Qiangguo1,Fang Haiyan1,Chen Xiao'an1,3,Nie Binbin1,4,Cui Puwei1,3 |
| 1.Key Laboratory of Water Cycle and Related Land Surface Processes,Institute of Geographic Science and Natural Resources Research,CAS,100101,Beijing;2.Graduate School of the Chinese Academy of Sciences,100049,Beijing;3.College of Resources and Environment,Huazhong Agriculture University,430070,Wuhan;4.College of Horticulture and Forestry Sciences,Huazhong Agriculture University,430070,Wuhan: China |
|
|
|
|
Abstract In this study,effects of soil and water conservation measures on runoff and sediment reduction in Chabagou Watershed from 1971 to 1980 are calculated by three methods: rainfall-runoff and rainfall-sediment statistical model,double-accumulative curve method and time series contrasting method separately.As a result,runoff reduction are 10.55%,6.18% and 26.67% and sediment reduction are 58.74%,63.40% and 72.77% accordingly.By analyzing the results of calculation and comparison with results of previous studies,three main points are concluded: 1) Governance model emphasizing on sediment storage dam has remarkable sediment reduction effects which is averaging about 65% and can effectively reduce peak discharge with an averaging runoff reduction effect more than 25% in the flood season;2) Annual runoff reduction effect is only averaging about 7% and the ratio of groundwater runoff to total runoff raised by 20.4%,which shows that sediment storage dam affect runoff by adjusting the ingredient proportion rather than reducing total runoff;3) The aim of water and soil conservation can not realized only by sediment storage dam for it does not change the conditions of hill slopes where soil erosion occurs,and instead vegetation restoration is an effective approach for ecosystem restoration and enhancement in eroded area of loess.
|
|
Received: 21 July 2009
|
|
|
|
|
|
|
