Effects of Bacteria Inoculation on Soil Hydrology and Erosion Processes of a Clay Loam Soil

Abstract

Biological Soil Crusts (BSCs) are complex microbial consortia interacting with topsoil. These communities form crusts that significantly influence soil hydrology and erosion by altering soil physical and chemical properties, thereby impacting water dynamics, nutrient cycling, and plant growth. This study investigates the effects of a microbial inoculum on soil hydrology and erosion for microplots under simulated rainfall. Strains of Peribacillus simplex, isolated from an erosion-prone area in Sicily, were inoculated in microplots then subjected to different rainfall intensities (low, intermediate, and high intensity). The results indicate that inoculated strains dominate the preexisting soil microbial community and enhance runoff and soil loss due to the exopolysaccharide (EPS) secretion, which can cause pore clogging. For high-intensity rainfalls, the investigation highlighted that the effect of microbial crusts decreases. The study underscores the complexity of BSCs' interactions with soil hydrology and erosion, highlighting the potential and limitations of microbial inoculation in managing soil stability and water retention in degraded ecosystems.