A quantitative study of the influence of soil organic carbon and pore characteristics on the stability of aggregates of the karst peak-cluster depression area in Southwest China

Purpose Rock desertification is the most serious ecological problem in karst areas and can easily cause soil structure instability. The aim of this work was to analyze the influences of organic carbon, carbon components and pore structural differences on the stability of aggregates in rocky desertification areas. Materials and methods Soil samples were collected from the karst peak-cluster depression area in Southwest China. Soil aggregate stability was determined by the Le Bissonnais (LB) method. The relationship between variables was analyzed via the structural equation model (SEM). Results and discussion There were significant differences in the stability of aggregates among different land uses in the study area: secondary forest (SF) > coppice forest (CF) > plantation forest (PF) > citrus plantation (CP) > cultivated land (CL). The main crushing mechanisms of aggregates were slaking and mechanical failure. Aggregate pores were mainly