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.