Effect of long-term strip tillage on soil macropore structure in cool black soil region of Northeast China

Soil pore structure is essential for storing and transporting water, and it can be affected by different tillage practices. Strip tillage (ST) is an innovative technology aimed at addressing the challenge of reduced crop yield caused by no-tillage (NT) in the cool black soil region of Northeast China. Nevertheless, what remains unclear is the influence of ST on soil pore structure in the cool black soil region. After conducting a 14-year long-term positioning experiment, this study investigated the variations in spatial distribution patterns of soil macropores under ST practice using X-ray computed microtomography (mu CT). The research also examined, the response of soil organic carbon (SOC) and soil bulk density to ST compared to conventional tillage (CT). This finding revealed that ST significantly increased the macroporosity (>25 mu m) at 0-20 cm depths in comparison with CT. The detailed analysis of soil pore size distribution revealed a significant increase in macroporosity of the >2000 mu m pore sizes in 0-10 cm layer by 144.79% because of ST. Furthermore, ST significantly increased pore connectivity at the 0-10 cm depth by 3.37% and pore fractal dimension at the 10-20 cm depth by 13.42%. Meanwhile, there was a significant correlation among the changes in soil bulk density, SOC content, macroporosity, pore connectivity, and pore tortuosity, indicating soil bulk density and SOC have a substantial impact on the pore structure. Overall, the implementation of ST leads to a significant enhancement in soil pore structure, improving the understanding of the regulatory mechanism of ST in the cool black soil region of Northeast China. This research aids in advancing the conservation and sustainable utilization of black soil.