生态与农村环境学报2026，Vol.42Issue(8)：1104-1113,10.DOI:10.19741/j.issn.1673-4831.2025.0554
围栏封育对退化高寒草甸土壤团聚体组成及稳定性的影响
Effects of Grazing Exclusion on Soil Aggregate Composition and Stability in Degraded Alpine Meadows
摘要
Abstract
Grazing exclusion is a widely implemented measure for restoring degraded alpine meadows on the Qinghai-Ti-betan Plateau,yet its effects on soil aggregate composition and stability remain unclear.In this study,0-20 cm soil sam-ples were collected from a degraded alpine meadow,an alpine meadow subjected to 4 years of grazing exclusion,and an alpine meadow subjected to 12 years of grazing exclusion in the Yangtze River source region.Dry sieving and wet sieving methods were employed to separate mechanically stable and water-stable aggregates of different sizes.Key aggregate stabil-ity indices,including mean weight diameter(MWD),geometric mean diameter(GMD),mass fraction of macroag-gregates(R0.25),and percentage of aggregate destruction(PAD),were determined to assess changes in aggregate stabili-ty following grazing exclusion.Furthermore,plant,soil,and microbial properties were measured to identify the key drivers underlying soil structural recovery.The results showed that the mass fractions of dry-sieved>5 mm and wet-sieved>0.25 mm aggregates increased after grazing exclusion,with significant differences observed after 12 years of enclosure,indica-ting that long-term grazing exclusion promoted the formation of macroaggregates.In contrast,the mass fractions of dry-sieved<2 mm and wet-sieved<0.25 mm aggregates significantly decreased after 12 years of enclosure,reflecting a shift in aggregate size distribution toward coarser fractions.The stability of soil aggregates followed the order GE12>GE4>DM.After 4 years of enclosure,water-stable aggregate stability significantly increased,while both mechanical and water-stable aggregate stability showed significant improvements after 12 years.Additionally,the PAD decreased significantly from 47.44%in DM to 15.98%-20.20%in GE4 and GE12.Random forest and partial least squares path modeling(PLS-PM)analyses revealed that soil pH,plant biomass,soil total organic carbon,and microbial biomass carbon are key drivers of soil aggregate stability.In conclusion,grazing exclusion enhanced aggregate stability by promoting the formation of macroaggregates,demonstrating its effectiveness as a management strategy for restoring soil structure in degraded alpine meadows.关键词
围栏封育/高寒草甸/土壤团聚体/土壤结构/生态治理Key words
grazing exclusion/alpine meadow/soil aggregates/soil structure/ecological restoration分类
农业科技引用本文复制引用
秦文萍,袁晖,孙铭阳,向明学,田丽慧,李晓燕,千文睿,刘翔..围栏封育对退化高寒草甸土壤团聚体组成及稳定性的影响[J].生态与农村环境学报,2026,42(8):1104-1113,10.基金项目
青海省科技厅项目(2024-ZJ-734) （2024-ZJ-734）
国家自然科学基金项目(42067070,32401448) （42067070,32401448）
