Comparison of land use in black soil regions between China and the United States based on terrain characteristics

Abstract

[Objective] Land degradation has emerged as a critical scientific concern in the black soil regions, which serve as the primary agricultural production bases worldwide. This study focuses on two black soil regions, namely northeast China and the Mississippi River basin in America, to investigate the variations and patterns of environmental characteristics across different black soil regions. The findings from this study will provide a theoretical foundation for a more comprehensive understanding of the mechanisms of black soil degradation. [Methods] Terrain factors such as slope, aspect, and terrain undulation were derived from DEM data using ArcGIS 10.2. Landform types were determined based on terrain undulation and elevation data. The characteristics of land use distribution were compared from four aspects, including terrain conditions, topographic distribution index, human activity intensity and soil erosion risk. [Results] The results indicated that: (1) The terrain conditions of Mississippi River basin in America were generally better than that of northeast China, with nearly 78% of the area having slopes less than 8°. This provided superior conditions for disseminating technology of conservation tillage. However, there were minimal differences in the distribution of aspects between the two black soil regions. (2) Grassland, cultivated land, and construction land had a negative correlation with slope in both regions, while forestland showed a positive correlation. Aspect had no significant impact on the spatial distribution of land use. Notably, land use on steep slopes was more intensive in northeast China, leading to a higher risk of potential land degradation. (3) The intensity of human activity in the two black soil regions was constrained by landform, indicating that the terrain undulation is an important constraint on the development and utilization of black soils. However, the Mississippi River basin exhibited greater human activity intensity compared to northeast China. Despite its relatively flat terrain, the potential environmental impacts in the Mississippi River basin require international attention. (4) Both black soil regions had more than 50% of medium-high risk areas for soil erosion, indicating a generally high level of land development. They both need to constrain the urban sprawl and enhance farmland protection to ensure the sustainable use of black soils. [Conclusion] This study suggests that the protection of black soil should consider terrain characteristics. In flat areas, a proper balance between urban development and the protection of cultivated land is imperative. When promoting conservation tillage technology on sloped croplands, local conditions should be considered. Furthermore, attention should be extended towards grassland, forest land, and other natural ecosystems to systematically prevent black soil degradation.

Keywords

• |land use|dem|topographic factors|landform division|black soil protection