Reasonable grazing may balance the conflict between grassland utilization and soil conservation in the semi-arid hilly areas, China  

作　　者：SUN Hui ZHAO Yunge GAO Liqian XU Mingxiang 

机构地区：[1]College of Forestry,Northwest A&F University,Yangling 712100,China [2]College of Soil and Water Conservation Science and Engineering,Institute of Soil and Water Conservation,Northwest A&F University,Yangling 712100,China

出　　处：《Journal of Arid Land》2024年第8期1130-1146,共17页干旱区科学（英文版）

基　　金：National Key Research and Development Program of China(2022YFD1300803);National Natural Science Foundation of China(42377357).

摘　　要：Soil erosion caused by unsustainable grazing is a major driver of grassland ecosystem degradation in many semi-arid hilly areas in China.Thus,grazing exclusion is considered as an effective method for solving this issue in such areas.However,some ecological and economic problems,such as slow grassland rejuvenation and limited economic conditions,have become obstacles for the sustainable utilization of grassland ecosystem.Accordingly,we hypothesized that the conflict between grassland use and soil conservation may be balanced by a reasonable grazing intensity.In this study,a two-year grazing fence experiment with five grazing intensity gradients was conducted in a typical grassland of the Loess Plateau in China to evaluate the responses of vegetation characteristics and soil and water losses to grazing intensity.The five grazing intensity gradients were 2.2,3.0,4.2,6.7,and 16.7 goats/hm2,which were represented by G1-G5,respectively,and no grazing was used as control.The results showed that a reasonable grazing intensity was conducive to the sustainable utilization of grassland resources.Vegetation biomass under G1-G4 grazing intensity significantly increased by 51.9%,42.1%,36.9%,and 36.7%,respectively,compared with control.In addition,vegetation coverage increased by 19.6%under G1 grazing intensity.Species diversity showed a single peak trend with increasing grazing intensity.The Shannon-Wiener diversity index under G1-G4 grazing intensities significantly increased by 22.8%,22.5%,13.3%,and 8.3%,respectively,compared with control.Furthermore,grazing increased the risk of soil erosion.Compared with control,runoff yields under G1-G5 grazing intensities increased by 1.4,2.6,2.8,4.3,and 3.9 times,respectively,and sediment yields under G1-G5 grazing intensities were 3.0,13.0,20.8,34.3,and 37.7 times greater,respectively,than those under control.This result was mainly attributed to a visible decrease in litter biomass after grazing,which decreased by 50.5%,72.6%,79.0%,80.0%,and 76.9%,respectively,under G1-G5 grazing inte

关 键 词：fence-controlled grazing rehabilitated grassland vegetation community characteristics soil erosion sediment biocrusts Loess Plateau 

分 类 号：S157[农业科学—土壤学]