Spatial Variations of Aquatic Bacterial Community Structure and Co-Occurrence Patterns in Coal Mining Subsidence Lake

Land subsidence created by underground coal mining has a critical influence on the structure and function of ecosystems in mining areas. However, knowledge of the aquatic bacterial community structure and interspecies interactions in subsidence lake is still limited. To address this, we collected water samples from a coal mining subsidence lake and its connected river and investigated the spatial distribution and co-occurrence patterns of the bacterial community using 16S rRNA amplicon sequencing. The results revealed that bacterial α-diversity in the subsidence lake, with a relatively high nutrient concentration, was higher than that in the river. Total nitrogen was the most essential environmental factor involved in structuring the bacterial community composition, while sulfate was the most crucial factor involved in shaping the bacterial functional composition. Compared to the river, subsidence lake network showed significantly higher modularity indices and more stable microbial networks , which presented more resistance to environmental disturbance. Keystone species in the subsidence lake and river included Clostridiaceae_1 , Shewanella , Flavobacterium, and Limnohabitans , which play vital roles in carbon, sulfur and nitrogen cycles and could coordinate core community to complete ecosystem processes. Moreover, functional analysis showed that assimilatory sulfate reduction process were major players in the sulfur cycle of the subsidence lake and its connected river ecosystem. Overall, our findings provide new insights into microbial community structure and assembly in subsidence lakes and their connected river ecosystems, with significant implications for the responsible utilization of water resources and the promotion of sustainable development in mining areas