Changes in Soil Physical and Chemical Properties during Vegetation Succession on Miyake-jima Island

The bare lands formed after volcanic eruptions provide an excellent opportunity to study the interactions between vegetation succession and soil formation. To explore the changes in soil physicochemical properties in the vegetation succession processes and the relationship between them, soil physicochemical properties of different volcanic ash accumulation on Miyake-jima Island were studied at different vegetation succession stages. The results showed that soil bulk density gradually decreased and that soil porosity, soil water content (SWC), pH, cation exchange capacity (CEC), soil total organic carbon (TOC), and total nitrogen (TN) increased significantly with vegetation succession. The physicochemical properties changes in the soil surface horizon were most obvious, and the deep soil accumulated a large amount of relatively stable soil carbon and nitrogen. The forest land formed a thicker organic matter horizon, accumulating more carbon and nitrogen than grassland, and the soil quality index (SQI) was higher than that of grassland and shrubland. In conclusion, our research indicates the significant change in soil physicochemical properties and the improvement in soil quality in the vegetation succession processes, emphasizing a significant relationship between vegetation succession and soil development in bare land