豆科作物与小麦-玉米轮作对土壤有机碳储量的影响OA

Through field-based rotational cropping trials on the North China plain,this study investigated variations in soil organic carbon stocks and sequestration levels following different legume crops rotated with winter wheat-summer maize,which was aiming to provide scientific theoretical support for enhancing organic carbon sequestration in grain-producing fields across the North China plain.Based on field-based diversified crop rotation trials,two rotation systems with two-year-three-crop were established,including peanut → winter wheat-summer maize(Sp-WM)and mung bean → winter wheat-summer maize(Sm-WM),with winter wheat-summer maize(WM-WM)double cropping serving as the control.Soil samples were collected at maize maturity in 2024 to determine soil organic carbon and organic carbon fraction content.Compared to WM-WM,legume crop rotations significantly increased organic carbon storage in the 0-40 cm soil layer.Sp-WM and Sm-WM soils showed respective increases of 11.76%and 14.54%in organic carbon storage,with significant increases of 46.63%and 57.65%in organic carbon sequestration,respectively.The rotation also substantially elevated active organic carbon fractions,particularly in the 0-10 cm topsoil layer,where reducible organic carbon and particulate organic carbon increased by 67.49%-71.97%and 101.35%-115.41%,respectively,indicating a more dynamic carbon pool structure.Additionally,carbon sequestration rates increased significantly by 15.39%-154.35%after rotation,with the highest increase in the carbon pool management index observed in the 0-10 cm soil layer(148.76%-162.03%).This indicated that introducing leguminous crops significantly enhanced soil carbon sink function and carbon pool quality.Compared with WM-WM,both rotation patterns significantly increased organic carbon storage,organic carbon sequestration,reactive organic carbon and phenolic organic carbon content,and carbon pool management index in the 0-40 cm soil layer,while markedly enhancing carbon sequestration rates in both the 0-10 and 20-40 cm layers.These findings could provide crucial scientific and theoretical support for soil carbon sequestration and sustainable management in farmland soils of the North China plain,which could be great significance for enhancing agricultural carbon sequestration potential and advancing green,low-carbon agricultural development.