中国草地学报2025，Vol.47Issue(8)：66-75,10.DOI:10.16742/j.zgcdxb.20240463
草地开垦对农牧交错带土壤有机碳组分的影响
Effects of Grassland Reclamation on Soil Organic Carbon Fractions in Agro-pastoral Ecotone
摘要
Abstract
The overexploitation of agro-pastoral systems has driven widespread grassland reclamation in northern China,accelerating soil carbon and nutrient depletion.However,the mechanisms underlying the responses of soil organic carbon(SOC)and its fractions to grassland cultivation remain unclear.In this study,we investigated the effects of grassland reclamation on soil physicochemical properties and SOC frac-tions across three representative sites in the agro-pastoral ecotone:Jianping(Liaoning),Youyu(Shanxi),and Yuzhong(Gansu).Cultivation significantly increased soil nitrate nitrogen but reduced SOC content by 24.17%.Among SOC fractions,labile free particulate organic carbon(fPOC)decreased significantly,whereas occluded particulate organic carbon(oPOC)and mineral-associated organic carbon(MAOC)remained unchanged.Random forest analysis identified soil electrical conductivity,moisture,and the carbon-to-nitrogen(C/N)ratio as the primary regulators of SOC and its fractions.Specifically,SOC and MAOC were mainly influenced by soil electrical conductivity and moisture,while the C/N ratio was the dominant driver of SOC and fPOC dynamics.Overall,grassland cultivation selectively depleted labile car-bon pools while maintaining oPOC and MAOC,a process largely mediated by shifts in soil electrical con-ductivity,moisture,and the C/N ratio,ultimately reshaping SOC distribution and stability.关键词
游离态颗粒有机碳/闭蓄态颗粒有机碳/矿物结合态有机碳/土壤理化性质Key words
Free particulate organic carbon/Occluded particulate organic carbon/Mineral-associated organic carbon/Soil physicochemical properties分类
农业科技引用本文复制引用
刘振鹏,唐士明,张斌,张桐瑞,徐学宝,袁凤钦,刘佳,王鑫宁,任杰,金轲..草地开垦对农牧交错带土壤有机碳组分的影响[J].中国草地学报,2025,47(8):66-75,10.基金项目
国家重点研发计划项目"精分区域耕地地力提升障碍因子与定向培肥路径研究"(2022YFD1900302) （2022YFD1900302）
内蒙古自治区2022年度引进高层次人才项目(2023NMRC003) （2023NMRC003）
