Context-Dependent Cross-Taxon Congruence Between Plants and Macrozoobenthos in Coal-Mining Subsidence Wetlands

Coal-mining subsidence wetlands are post-industrial landscapes whose sustainable management requires coordinated biodiversity monitoring across multiple taxonomic groups. We surveyed wetland plants and macrozoobenthos across nine coal-mining subsidence wetlands at three subsidence stages in China’s Jining Coalfield over three seasons. We evaluated cross-taxon congruence in α-diversity and community composition, together with environmental associations. Results indicated that plant species richness and Shannon–Wiener diversity were lower at the middle stage than at the late stage, whereas macrozoobenthos richness was higher at the late stage than at the initial and middle stages. Overall species richness was positively correlated between taxa, whereas stage- and season-specific congruence occurred only for Pielou’s evenness at the initial stage (negative) and Shannon–Wiener diversity in autumn (positive). Community composition varied among stages and exhibited significant cross-taxon congruence (p < 0.01). Environmental analyses indicated some shared associations but different overall response patterns between communities. Thus, the development of coal-mining subsidence wetlands involved asynchronous and context-dependent community reorganization rather than uniform cross-taxon convergence. These findings support stage-sensitive, multi-taxon monitoring to improve biodiversity assessment and provide a case-based reference for the science-based conservation, ecological restoration, and sustainable management of similar post-industrial wetland systems.