Higher species diversity improves soil water infiltration capacity by increasing soil organic matter content in semiarid grasslands

Understanding the mechanisms mediating biodiversity effects on ecosystem functions and services is considered a core issue in ecological and environmental sciences. We studied the direct and indirect effects of plant diversity on soil organic carbon storage and soil infiltration capacity in semiarid grasslands. Plant species diversity enhances soil organic carbon and soil infiltration capacity via multiple plant-soil feedback mechanisms in long-term natural restoration grasslands. Plant species diversity increases community productivity, resulting in increasing soil carbon storage, which improves soil infiltration capacity by influencing soil aggregate stability and porosity. The present study indicates that plant species diversity is conducive to increasing atmospheric CO2 sequestration and reducing the risk of soil erosion. Our study provides a framework for interpreting the relationships among plant species diversity, soil organic carbon, and soil infiltration capacity to understand plant-soil feedback mechanisms in semiarid grasslands.