A database of SOC, TN, and SWC for various land-use types and soil textures

<b>Responses of soil carbon-nitrogen-water trade-offs to land-use change and soil texture on the Loess Plateau</b>The conversion of cropland to vegetated land has significantly altered deep soil carbon, nitrogen, and water dynamics. However, their interrelationships remain insufficiently explored. In this study, 0–400 cm soil profiles were collected from grassland, shrubland, and forestland across four soil textures (clay, clay loam, loam, and sandy soil) in the desert-loess transitional zone of the Loess Plateau to examine the trade-offs among soil carbon, nitrogen, and water in response to land-use changes and soil texture. The results revealed distinct vertical distributions of soil organic carbon (SOC), total nitrogen (TN), and water storage, with substantial accumulation in deep soil layers (100–400 cm). Pronounced trade-offs were identified between SOC and soil water content (SWC), as well as between TN and SWC, whereas no trade-off was observed between SOC and TN. These findings suggested that the sequestration of SOC and TN occurred at the expense of water depletion and that nitrogen input facilitated soil carbon sequestration. Significant variations in carbon-nitrogen-water trade-offs were observed among land-use types, with forestland identified as the most favorable for maintaining a balance among these components. Additionally, soil texture was found to be the dominant factor regulating carbon, nitrogen, and water in the 0–400 cm profile, outweighing the effects of land use and soil depth. Clay and clay loam soils exhibited stronger coordination in carbon-nitrogen-water coupling, whereas in less favorable textures such as sandy soils, appropriate land management practices are necessary. This study provides a scientific foundation for designing effective land management and vegetation restoration strategies in arid and semi-arid regions.