黄土丘陵沟壑区典型小流域水土流失治理蓄水保土效益研究

BENEFIT ANALYSIS OF SOIL AND WATER CONSERVATION IN CONTROLLING SOIL AND WATER LOSS IN SMALL WATERSHED OF THE LOESS HILLY AND GULLY REGION

以黄土丘陵沟壑区河洛图（治理流域）和万盛隆（对照流域）两个小流域为研究对象,通过测定其土壤含水率、土壤容重、土壤养分、输沙模数和径流模数等指标,进而对比分析水土保持措施蓄水保土效益,研究结果可为该区水土保持工作提供技术指导。研究表明：河洛图小流域的土壤含水率、土壤孔隙度、土壤粒径和土壤容重等指标均优于万盛隆小流域;万盛隆小流域表层（0~20cm）土壤有机质、全氮、全磷、全钾、速效钾含量分别比河洛图低20.1%,36.3%,18.6%,15.2%,39.7%,速效磷含量不足河洛图的50%;万盛隆小流域的径流模数均比河洛图小流域大,部分年限达到其1.5倍,输沙模数平均为河洛图的151%;工程措施与植物措施综合配置是实现水土保持蓄水保土效益最大化的必然选择。

This paper chose Heluotu（ manmade） and Wanshenglong（ compared） that are two different kinds of small watersheds in loess Hilly and Gully Region,by determining their indices,including soil water content,bulk density,fertility,sediment and runoff,contrasted effective-ness benefit analysis of soil and water conservation in controlling soil and water loss,technical advice can be provided for conservation of water and soil in loess Hilly and Gully Region. The results were as follows：（ 1） The soil water content,porosity,particle and bulk density in the Heluotu are all better than Wanshenglong＇s.（ 2） The shallow soil（ 0-20cm） of Wanshenglong the content of soil organic matter,tolal nitrogen,tolal phosphorus,total potassium and available potassium are less than Heluotu＇s by 20. 1%,36. 3%,18. 6%,15. 2%,39. 7%,the content of available phosphorus is less than Heluotu＇s one half.（ 3） The runoff modulus of Wanshenlong small watershed is bigger than Heluotu＇s,some year＇s are equal to 1. 5 times,the averages of sediment transport coefficient is equal to 151% in Heluotu＇s.（ 4） Taking the biological and engineering measures to Control Soil and Water loss in Small Watershed achieves good effect,it is an inevitable choice.