Mechanisms of Soil Carbon and Nitrogen Sequestration Under Tillage-fertilizer Interactions: Field study in Loess Plateau

The study was performed in the Experimental Demonstration Base of Conservation Tillage of Shanxi Agricultural University, Taigu District, Jinzhong City, Shanxi Province, China. Fresh soil, undisturbed soil, and cutting ring soil samples were collected from the 0-10, 10-20, 20-40, and 40-60 cm soil layers in various plots of the experimental field before the start of the experiment in 2016 (Before the experiment, Be) and during the winter wheat harvest in 2020-2023. To maintain the soil physical properties, such as porosity and water content in its natural state, the samples of undisturbed soil and cutting ring soil were obtained by the press-in method. Among them, fresh soil was used for SSA determination, undisturbed soil was partly used to measure soil aggregates and other related properties, and partly for SOC, STN, and SPA determinations, and cutting ring soil was used to measure soil three-phase properties.本研究在中国山西省晋中市太谷区山西农业大学保护性耕作实验示范基地开展。2016年实验启动前（简称实验前，Be）以及2020-2023年冬小麦收获期，研究人员于试验田各小区的0-10、10-20、20-40、40-60 cm土层采集新鲜土、原状土与环刀土样本。为使原状土与环刀土的孔隙度、含水量等物理性质保持自然状态，两类样本均采用压入法采集。其中，新鲜土用于比表面积（SSA）的测定；原状土一部分用于测定土壤团聚体及其他相关理化性质，另一部分用于土壤有机碳（SOC）、全氮（STN）与SPA的测定；环刀土则用于测定土壤三相性质。