Effects of chemical properties of mixed leaf litter, phyllosphere microbial communities, and leaf litter decomposition

Abstract Purpose Litter decomposition is crucial for maintaining soil fertility, regulating energy flow and nutrient balance in forest ecosystems. However, current research often focuses on the role of soil microorganisms in litter decomposition while neglecting the role of phyllosphere microorganisms. Therefore, this study focuses on the impact of phyllosphere microorganisms on litter decomposition. Methods In mid-October 2022, litter collectors were deployed, and the collected leaf litter from different tree species was subsequently placed into litterbags. In mid-April 2023, plastic frames were placed under the forest canopy, and the decomposition bags were suspended in the air with protective covers installed on top. Sampling was conducted in mid-July 2023. The leaf litter in the decomposition bags was mixed and weighed for the determination of chemical properties, microbial indicators and other parameters. Results There are significant differences in the chemical properties, weight loss rate (WLR) and decomposition rate (DR) of different leaf litter. At the same time, it was found that the chemical properties are significantly correlated with the phyllosphere microorganisms, the WLR and the DR. Moreover, the microbial community composition and diversity of the mixed leaf litter are also significantly different from those of a single tree species. Conclusion The various indicators of the mixed leaf litter show a significant intermediate effect, and the mixed leaf litter can reshape the microbial community structure at the leaf interface. At the same time, chemical properties and microbial communities can affect the decomposition of leaf litter. These research results have important theoretical and practical value for promoting the nutrient cycling in forest areas and maintaining the stability of artificial forest ecosystems.