Forest gaps mediate the structure and function of the soil microbial community in a Castanopsis kawakamii forest

Forest gaps affect the soil microbial community structure and soil function by altering the ambient environment. This study aimed to explore the effects of environmental factors on soil microbial communities and enzyme activities in Castanopsis kawakamii forest gaps. The soil properties, soil enzyme activities, and microbial composition inferred by high-throughput sequencing were determined to quantify the soil eco-physiological functions. A redundancy analysis and linear model (LM) were further used to test the significance of forest-gap effects on soil microbial community structure and its function. The formation of gaps significantly increased the canopy openness (CO) and soil temperature (ST), and the small gaps (GS) and large gaps (GL) were the most conducive to the accumulation of soil total nutrients. Soil characteristics in GS provided a favorable environment for microbial growth, which promoted the soil microbes and function in these forest gaps. The soil physical–chemical properties in GM were relatively low and influenced its soil function, resulting in this gap size having the lowest enzyme activities. Forest gaps govern the soil microbiomes and soil function by regulating gap characteristics and soil properties. Meanwhile, the presence of dominant microorganisms promoted enzyme activities. These results could help further our understanding of the impact of forest gaps on the soil process and forest succession.