草地学报2026，Vol.34Issue(6)：2077-2089,13.DOI:10.11733/j.issn.1007-0435.2026.06.011
氮添加对高寒草甸表层土壤有机碳及其组分的初期影响
Initial Effects of Nitrogen Addition on Surface Soil Organic Carbon and its Components in an Alpine Meadow
摘要
Abstract
To elucidate the initial effects of nitrogen deposition on soil organic carbon(SOC)and its stability in alpine meadows,we conducted a field nitrogen addition experiment in the eastern Qilian Mountains.Aboveg-round biomass,soil physicochemical properties,enzyme activities,and SOC fractions were measured,and their key drivers were identified using variance partitioning.Nitrogen addition significantly increased aboveg-round biomass but reduced cellulase and β-glucosidase activities(P<0.05).Particulate organic carbon(POC)content and proportion decreased markedly,whereas easily oxidizable organic carbon(EOC)and mineral-associated organic carbon(MAOC)increased significantly(P<0.05).POC dynamics were mainly regulated by total phosphorus and carbon-acquiring enzymes,MAOC was closely associated with aboveground biomass,pH,and β-glucosidase,while EOC was primarily driven by available phosphorus and cellulase.Overall,microbial biomass carbon(17%)and dissolved organic carbon(14.1%)primarily explained short-term SOC variations.In summary,nitrogen addition enhanced soil carbon pool stability by promoting plant carbon inputs,modulating enzyme activities,and reshaping the distribution of SOC fractions.These findings reveal the path-ways through which nitrogen deposition stabilizes SOC in alpine meadows,providing critical insights into carbon cycling processes and the carbon sequestration potential of fragile ecosystems under nitrogen enrichment.关键词
高寒草甸/氮添加/活性碳组分/碳库稳定性/方差分解Key words
Alpine meadow/Nitrogen addition/Activated carbon components/Carbon pool stability/Variance decomposition分类
农业科技引用本文复制引用
岳磊,唐庄生,孟天乐,杨健,马晶,张文柳,杨洁..氮添加对高寒草甸表层土壤有机碳及其组分的初期影响[J].草地学报,2026,34(6):2077-2089,13.基金项目
国家自然科学基金项目(32360345) （32360345）
中国农业大学对口支援项目(GSAU-DKZY-2024-004) （GSAU-DKZY-2024-004）
甘肃农业大学伏羲青年英才(GAUfx-04Y06) （GAUfx-04Y06）
甘肃省杰出青年基金(24JRRA632)资助 （24JRRA632）
