The diversity of plant communities in different habitats can lead to distinct methanotrophic communities

Abstract

Methanotrophic communities are susceptible to environmental interference in natural ecosystems. However, little is known about methanotrophs and their drivers in the riparian zone ecosystem. Therefore, the soil methanotrophic community structure, assembly process, and their driving factors were examined in five habitats in the riparian zone ecosystem of Three Gorges Reservoir in China. Soil samples were collected from the woody plant community, perennial plant community, annual plant community, perennial mixed annual plant community, and bare land in the riparian zone areas. We assessed plant community diversity, analyzed soil physiochemical properties, and measured enzyme activities to find the driving factors for the methanotrophic community. The findings revealed that Methylosarcina, Methylocystis, and rice paddy clusters dominated habitats. They preferred different pH levels and plant diversity. The diversity of the soil methanotrophic community was greater in vegetation-covered areas than on bare land. Likewise, the co-occurrence network of soil methanotrophs was more complex in vegetation-covered areas than in bare land, indicating a more stable community structure. Soil nitrogen, catalase, and plant diversity influence stability and diversity. During the transformation from bare land to plant community, the assembly process of the soil methanotrophic community converted from stochastic to deterministic processes, in which dispersal limitation and homogenous selection played prominent roles and were primarily influenced by soil pH and plant diversity. This research helps us understand the evolution of methanotrophs during vegetation restoration. It can also help us find plant communities that can effectively sequester carbon pools and plant them in riparian zones around reservoir systems to maintain soil and water quality.