Occurrence Regularity of Silt–Clay Minerals in Wind Eroded Deserts of Northwest China

Abstract

Wind erosion desertification is the most serious type of land degradation in Northwest China, so it is an important task for ecological management in the region. As the core of ecological management, soil quality is mainly affected by the presence of silt–clay content. Therefore, the grasp of its occurrence regularity is the key to controlling wind erosion desertification. At present, research on silt–clay contents is mainly independent in each local area and lacks integrity, which makes it difficult to meet the overall evaluation and planning requirements. To this end, this paper reviewed the related studies on the occurrence and control of wind erosion desertification in recent years and collected nearly 300 relevant silt–clay content data points. We studied the occurrence regularity of silt–clay content during the occurrence and treatment of wind erosion desertification and revealed the mechanism of silt–clay content in different processes. On this basis, the degree of wind erosion desertification in the major areas of Northwest China in the last five years was evaluated by calculations based on soil typing theory, and the fractal dimension interval (2.41–2.53) for the critical discrimination of desertification in these areas was obtained. The results showed that there were obvious distribution intervals of silt–clay content for different degrees of wind erosion desertification. Qualitative changes in soil quality during degradation ranged from light to moderate wind erosion desertification. The occurrence and control of wind erosion desertification were largely affected by the processes of silt–clay particles loss and aggregation. Among the three main treatment measures, biological measures enhanced silt–clay content most significantly. In this study, the occurrence regularity of silt–clay minerals in wind erosion desertification in Northwest China was revealed as a whole. This study provided a preliminary overall judgement of the dynamic evolution of wind erosion desertification, which provided a reference for the overall evaluation and global governance planning of wind erosion desertification in Northwest China.