Effect of Ridging Shapes on the Water–Salt Spatial Distribution of Coastal Saline Soil

Abstract

The Yellow River Delta, located in China, experiences prevalent soil salinization and serves as a crucial ecological management zone within the Yellow River Basin. The shallow groundwater depth and high mineralization contribute to salt accumulation in the soil, which has a negative impact on crop growth. The sustainable use of saline land in the Yellow River Delta hinges on managing the soil salinity within the crop root zone. This study investigated the spatial distribution of soil salinity in coastal saline soil in the Yellow River Delta under various ridging configurations: triangular, arch, and trapezoidal, using flat land as a control. It also examined the impact of evaporation on soil salinity migration. The findings revealed that the ridge–furrow system successfully caused salt to accumulate in the superficial layer of the ridge. Among the three ridge shapes, the triangular ridge was the most effective at concentrating salt on the ridge surface, with 54.04% of the salt mass accumulation in the ridge’s top layer (0–1 cm) and with the furrow bottom achieving a maximum desalination rate of 93.07%. The results implied that the triangular ridge fostered a favorable soil environment for crop growth by minimizing the salt content in the furrow. This research provides a theoretical foundation for the sustainable advancement of saline–alkali agriculture in the Yellow River Delta, which can lead to higher crop yields and better land management practices.