Geographical and environmental distance differ in shaping biogeographic patterns of microbe diversity and network stability in lakeshore wetlands

Abstract

Soil microorganisms play a crucial role in wetland ecosystems, but the specific mechanisms underlying their diversity and network stability across lakeshore wetlands, as well as their importance in microbial ecology, are still poorly understood. Here, we analyzed the biogeographical pattern and network stability of lakeshore wetland microbial communities across a regional scale, and identified the primary factors that influence their composition. The results revealed that α-diversity of wetland bacteria decreased linearly with increasing longitude and latitude, whereas the α-diversity of fungal showed an increasing trend in lakeshore wetlands. Species richness was the principal way that the biogeographical pattern of α-diversity was expressed. The β-diversity of soil microbial in lakeshore wetlands has a significant geographical attenuation pattern. Fungal communities were influenced by stochastic spatial diffusion, while bacterial communities were influenced by deterministic environmental filtration as they transition from semi-arid to arid regions. Community network stability was specifically determined by bacterial and fungal diversity. Structural equation modelling revealed that spatial distance and climate indirectly affect bacterial diversity by influencing soil and plant diversity, which in turn affects feedback network stability. These findings show that the geographical pattern of soil microbial diversity in lakeshore wetlands influences network stability at the spatial scale, offering insights into the adaptation of wetland ecosystem diversity and stability at the regional level.