Fractal characteristics and stability of soil aggregates in karst rocky desertification areas

Abstract

Karst rocky desertification is one of the major ecological and environmental problems that threaten the sustainable development of southwestern China. This study focuses on a case study of the small watershed in Chenqi where karst rocky desertification is particularly severe. This paper considers samples of soils from six different land use patterns in Chenqi village. Various correlations are observed by using fractal theory, including an emerging model for studying soil aggregates. This study demonstrates how the fractal characteristics of soil structure and the stability of soil aggregates are crucial to better understanding karst rocky desertification. The fractal dimension of different land use patterns can be used to indicate the magnitude of soil destruction. Soil fractal dimension can be applied using different methods to characterize the changes in factors influencing the stability of soil structure. The results indicate a significant negative relationship between fractal dimension of soil aggregates and large aggregate content (of diameters 5–10 mm) and a significant positive relationship between fractal dimension and micro-aggregate content (<0.25 mm). The fractal dimension of soil aggregates is also significantly negatively correlated with both clay content and organic matter content. These results suggest that fractal dimension can be used as a reliable indicator of soil quality and presents advantages compared to using mean weight diameter.