Effects of the “Conversion of Cropland to Forest and Grassland Program” on the Water Budget of the Jinghe River Catchment in China
- Guo Yu Qiu *a,
- Jing Yinb,
- Fei Tianc and
- Shu Genga
- a Key Lab. for Urban Habitat Environment Science and Technology, School of Environment and Energy, Shenzhen Graduate School of Peking Univ., Shenzhen 518055, China
b China Institute of Water Resources and Hydropower Research, No. 1 Yuyuantan South Rd., Haidian District, Beijing 100038, China
c College of Resources Science and Technology, Beijing Normal Univ., No. 19, Xinjiekouwai St., Haidian District, Beijing 100875, China. Assigned to Associate Editor Minghua Zhang
a G.Y. Qiu and S. Geng, Key Lab. for Urban Habitat Environment Science and Technology, School of Environment and Energy, Shenzhen Graduate School of Peking Univ., Shenzhen 518055, China
In 1999 China adopted the “Conversion of Cropland to Forest and Grassland Program” (CCFGP), a nationwide ecological recovery program, to minimize wide-scale soil erosion and vegetation degradation in China, as well as to improve water budgeting results. In the 10 yr since implementation, the CCFGP has resulted in the recovery and reforestation of >100,000 km2 of cropland and bare land, though the quantitative effect of this program on catchment water budget is not entirely clear. Therefore, we used the Soil and Water Assessment Tool to evaluate and quantify the effects of the CCFGP on the water budget of the Jinghe River catchment, a tributary of the Yellow River covering the central region of the Loess Plateau. Our results indicated that precipitation had dropped by 12.0% from the 1970s (611.6 mm) to the 2000s (538 mm) and that there was a corresponding 25.2% decrease in humidity index from 0.48 to 0.36. Before the CCFGP's implementation, forest and grassland had been decreasing, while bare land, cropland, and shrub land had been increasing. After the implementation of the CCFGP, the opposite trend was observed. Moreover, streamflow increased by about 15 and 20% for the upstream and middle stream subbasins, respectively, while soil water content also showed an obvious increase. Over the same period, evapotranspiration decreased by 5.2 and 13.5 mm and runoff decreased by 37.5 and 38.6% in the two subbasins. The same trends were obtained in the downstream subbasin, where changes were even greater. As a result of the reduced runoff and evapotranspiration, utilization of water resources was more efficient and ecological environment was improved under the CCFGP policy. Our results indicate the CCFGP resulted in a favorable ecological impact and should therefore be maintained.Please view the pdf by using the Full Text (PDF) link under 'View' to the left.
Copyright © 2011. . Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.