黄土丘陵区退耕草地土壤碳库管理指数对放牧的响应  

Response of Soil Carbon Pool Management Index of the Revegetated Grasslands to Grazing in the Hilly Loess Plateau Region

作　　者：马宁 赵允格[2,3] 马昕昕[2] 李雯 乔羽 孙会 许明祥[2,4] MA Ning;ZHAO Yun-ge;MA Xin-xin;LI Wen;QIAO Yu;SUN Hui;XU Ming-xiang(College of Forestry, Northwest A&F University, Yangling,Shaanxi Province 712100, China;Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling, Shaanxi Province 712100, China;College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi Province 712100, China;Institute of Soil and Water Conservation, Northwest A&F University, Yangling, Shaanxi Province 712100, China)

机构地区：[1]西北农林科技大学林学院,陕西杨凌712100 [2]中国科学院水利部水土保持研究所,陕西杨凌712100 [3]西北农林科技大学资源与环境学院,陕西杨凌712100 [4]西北农林科技大学水土保持研究所,陕西杨凌712100

出　　处：《草地学报》2022年第5期1043-1053,共11页Acta Agrestia Sinica

基　　金：中国科学院“西部之光”交叉团队项目-重点实验室合作研究专项(2019);国家自然科学基金项目(41771318,42177345)资助。

摘　　要：为研究放牧强度对黄土丘陵区退耕草地土壤有机碳库质量的影响,本试验以神木、定边、安塞和固原典型退耕草地为研究对象,同区20年以上封禁草地和坡耕地为对照,研究轻、中、重度(记为G1,G2和G3)放牧强度下0~20 cm土壤有机碳(Soil organic carbon,SOC)含量、活性有机碳(Labile organic carbon,LOC)含量和碳库管理指数(Carbon pool management index,CPMI)变化特征。结果表明:除固原外,其余三个地区不同放牧强度下SOC含量较各区封禁地和坡耕地未显著降低,G1和G2强度下LOC含量较各区封禁地和坡耕地未显著降低。定边和安塞CPMI在G1和G2放牧强度下与各区封禁地和坡耕地无显著差异;神木CPMI在G1放牧强度下与该区封禁地和坡耕地无显著差异,G2和G3强度显著低于封禁地;固原不同放牧强度下CPMI显著低于该区封禁地(P<0.05),但高于坡耕地。表明轻度放牧不会引起黄土丘陵区土壤有机碳库质量降低,重度放牧显著降低碳库质量。The objective of this study was to elucidate the effect of different grazing intensities on soil organic carbon pool quality of the revegetated grasslands in the Hilly Loess Plateau Region.The grasslands that were excluded from grazing for more than 20 years and the sloping farmlands were selected as the controls for the study in Shenmu,Dingbian,Ansai,and Guyuan.Soil organic carbon(SOC)contents,labile organic carbon(LOC)contents,and carbon pool management index(CPMI)in the 0~20 cm soil layer in light,moderate and heavy grazing intensities(were recorded as G1,G2,and G3)in typical revegetated grasslands were investigated in each region.Results showed SOC contents under different grazing intensities and LOC contents under G1 and G2 grazing intensities were insignificantly decreased compared with enclosed plots and sloping farmlands of each region in the other three regions except Guyuan.The CPMI under G1 and G2 grazing intensities were insignificantly different from their enclosed plots and sloping farmlands in Dingbian and Ansai.The CPMI was insignificantly different from its enclosed plots and sloping farmlands under G1 grazing intensity and was significantly lower than its enclosed plots under G2 and G3 grazing intensities in Shenmu.In addition,the CPMI under different grazing intensities was significantly lower than its enclosed plots(P<0.05),but higher than its sloping farmlands in Guyuan.The results indicated that the soil organic carbon pool quality did not decrease under light grazing intensity,while it significantly decrease under heavy grazing intensity in the Hilly Loess Plateau region.

关 键 词：放牧强度 土壤有机碳 活性有机碳 碳库管理指数 封禁 

分 类 号：S812.2[农业科学—草业科学]