水土保持研究2025，Vol.32Issue(4)：50-58,9.DOI:10.13869/j.cnki.rswc.2025.04.024
降水变化下黄土高原西部荒漠草原土壤团聚体稳定性变化特征及其影响因素
Changes in soil aggregate stability and its influencing factors in the desert steppe of the western Loess Plateau under precipitation variation
摘要
Abstract
[Objective]This study aims to analyze how precipitation changes affect the distribution and stability of soil aggregates in desert steppes and then to explore their main regulating factors,providing a scientific basis for evaluating changes and trends in soil carbon pools in desert steppes in the context of global climate change.[Methods]A field experiment was conducted in the desert steppe of the western Loess Plateau,incorporating five different precipitation gradients(-40%,-20%,0%,+20%,+40%).By monitoring soil physicochemical properties,enzyme activity,and plant growth characteristics,the study revealed the patterns and influencing factors of changes in the distribution and stability of soil aggregates under precipitation changes.[Results](1)Increased precipitation significantly increased the number of small aggregates(0.25～2 mm)and reduced the number of micro-aggregates(0.053～0.25 mm).Under all precipitation conditions,micro-aggregates had the largest proportion.The mean weight diameter(MWD)of aggregates followed the order of+40%>+20%>control>-20%>-40%precipitation treatments,with MWD under extreme precipitation increase(+40%)being signi-ficantly higher than those under extreme precipitation reduction(-40%)and control treatments.(2)Increased precipitation enhanced aggregate stability by promoting plant growth(litter mass,cover,and aboveground biomass were all highest under the+40%precipitation treatment),improving soil physicochemical properties,and increasing the activity of four soil enzymes(β-glucosidase and cellobiohydrolase were significantly higher than in the control and precipitation reduction treatments).[Conclusion]Increased precipitation in the desert steppe of the arid and semi-arid regions of Northwest China promotes the development of soil aggregates and improves aggregate stability.Plants,soil physicochemical properties,and soil enzyme activities jointly regulate the distribution and stability of soil aggregates.关键词
降水变化/土壤团聚体/植物生物量/土壤酶活性/半干旱草地Key words
precipitation change/soil aggregates/plant biomass/soil enzyme activity/semi-arid grassland分类
农业科学引用本文复制引用
魏曦,张丽华,蒋小玉,任晓彤,包鹏斌..降水变化下黄土高原西部荒漠草原土壤团聚体稳定性变化特征及其影响因素[J].水土保持研究,2025,32(4):50-58,9.基金项目
国家自然科学基金(41761043,41201196) （41761043,41201196）
西北师范大学青年教师科研能力提升计划项目(NWNU-LKQN2020-06) （NWNU-LKQN2020-06）
甘肃省科技计划项目(20YF3FA042) （20YF3FA042）
