Structure and development of bacterial community in decomposing deadwood and soil affected by changes in microclimatic conditions

Fine woody debris (FWD) is a crucial yet often overlooked component of forest ecosystems, providing a dynamic habitat for microbial communities and playing a key role in carbon and nutrient cycling. In managed forests with low deadwood stocks, FWD decomposition may enhance soil fertility by facilitating microbial nutrient cycling. However, how canopy cover influences microbial communities in decomposing FWD and surrounding soil remains insufficiently understood.To address this, we conducted a ten-year experiment manipulating canopy cover to examine the decomposition of FWD from Fagus sylvatica and Abies alba. Our study revealed that canopy manipulation significantly affected bacterial diversity in both surrounding soil and decomposing wood. While bacterial community structure in FWD was primarily influenced by decomposition time, tree species and canopy conditions also played a role. We identified bacterial taxa associated with carbohydrate utilization, fungal biomass degradation, and nitrogen fixation, highlighting the diverse functional roles of bacteria in FWD decomposition.These findings emphasize the complex ecological interactions shaping deadwood decomposition and nutrient cycling in forest ecosystems. The interplay between FWD decomposition time, tree species, and microclimatic variability influences microbial community dynamics, with bacteria acting as a more stable component of the decomposer community compared to fungi. This stability may be critical for sustaining decomposition and nutrient turnover despite environmental fluctuations. Future research should further investigate the functional potential of microbial communities to better understand their contributions to nutrient cycling under changing environmental conditions.