南方农业学报2025，Vol.56Issue(4)：1137-1146,10.DOI:10.3969/j.issn.2095-1191.2025.04.012
土壤团聚体有机碳矿化对秸秆添加和水分变化的响应
Response of organic carbon mineralization in different soil aggregates to straw addition and moisture variation
摘要
Abstract
[Object]This study investigated the effects of straw addition on organic carbon mineralization in soil aggre-gates under varying moisture conditions,aiming to elucidate the mechanisms underlying straw incorporation in soil or-ganic carbon transformation and stabilization.[Method]Two types of soil(sandy and clay)were selected for the study.Using the wet sieving method,3 size fractions of aggregates(>0.25 mm,0.25-0.053 mm and<0.053 mm)were obtained.An indoor microcosm cultivation experiment was conducted with no straw added as a control,the differences in organic carbon mineralization characteristics of different particle-size aggregates were observed under straw addition and soil moisture settings as 40%and 60%of field water holding capacity(WHC).[Result]Straw addition enhanced CO2 emis-sion rates and cumulative CO2 release in both while soil and aggregates of all sizes,with cumulative CO2 release in straw added treatments being as 1.2-1.7 times as that in controls without straw.Organic carbon mineralization rates and cumula-tive mineralization were greater under 60%WHC compared to 40%WHC.Increasing moisture from 40%to 60%could elevate cumulative CO2 release by an average of 15.2%in whole soil and 67.9%across aggregate sizes.Clay soil exhibited more pronounced responses,reaching a maximum cumulative CO2 release of 3453.27 mg/kg.Furthermore,straw addi-tion amplified the disparity in cumulative CO2 release between 60%WHC and 40%WHC treatments in clay soil.Clay ag-gregates demonstrated stronger response to moisture and straw addition than sandy soil.Moreover,the cumulative CO2 release of different soil aggregates were different.In sandy soil,the order was>0.25 mm,0.25-0.053 mm,<0.053 mm,and whole soil.In clay soil,the order was>0.25 mm,<0.053 mm,0.25-0.053 mm,and whole soil.Partial least squares(PLS)structural equation model analysis identified straw addition,soil moisture content,and soil physical and chemical properties as key drivers of soil organic carbon mineralization,while aggregate size showed no significant effect on soil aggregate cumulative mineralization(P>0.05).[Conclusion]Although differences in organic carbon mineralization among aggregate sizes are minimal,but exhibits strong responses to straw addition and moisture.High soil moisture con-tent promotes the mineralization of organic carbon in soil aggregates,which is conducive to improving the carbon supply capacity of the soil.关键词
土壤团聚体/有机碳矿化/土壤水分/秸秆添加Key words
soil aggregates/organic carbon mineralization/soil moisture/straw addition分类
农业科技引用本文复制引用
赵玉蝶,王兴来,余洁,苗淑杰,乔云发..土壤团聚体有机碳矿化对秸秆添加和水分变化的响应[J].南方农业学报,2025,56(4):1137-1146,10.基金项目
国家自然科学基金项目(42130506) （42130506）
江苏省碳达峰碳中和科技创新专项(BE2022425) National Natural Science Foundation of China(42130506) （BE2022425）
Jiangsu Carbon Peak and Carbon Neutral Science and Technology Innovation Project(BE2022425) （BE2022425）
