三江源退化高寒草甸土壤代谢产物特征及其与土壤环境因子的相关性OA

[Objective]This study examines soil metabolite variations in degraded alpine meadows of the Sanjiangyuan region,identifies key metabolic pathway shifts,and assesses their correlations with soil environmental factors.The findings provide scientific insights into degradation drivers and soil ecological responses.[Method]This study focuses on alpine meadows in Sanjiangyuan National Park,Maqin County,Guoluo Tibetan Autonomous Prefecture,Qinghai Province.It uses untargeted LC-MS/MS metabolomics to analyze soil metabolites across a degradation gradient,including non-degraded,lightly degraded,moderately degraded,and severely degraded meadows.The study also examines correlations between key differentially expressed metabolites and soil environmental factors.[Result]A total of 8 451 metabolites were identified,with lipids and lipid-like molecules being the most abundant(26.81%).Soil degradation significantly altered metabolite types and contents,with the most significant differences observed between heavily degraded and other meadow types.The top 20 signature metabolites included carboxylic acids,fatty acyls,organic nitrogen compounds,and sphingolipids.Key metabolic pathways affected were linoleic acid metabolism,ABC transporters,phospholipase D signaling,and sphingolipid signaling.Redundancy analysis revealed significant correlations between soil metabolites and environmental factors such as organic matter,water content,total nitrogen,total phosphorus,pH,and urease activity.[Conclusion]The types of signature metabolites,differentially expressed metabolites,and major metabolic pathways in alpine meadow soils varied significantly across degradation levels.These variations were hypothesized to correlate strongly with changes in environmental factors such as soil organic matter,water content,total nitrogen,total phosphorus,pH,and soil urease.[Ch,6 fig.2 tab.55 ref.]