Environmental factors at dissimilar spatial scales influence plant and microbial communities in restored wetlands

Identifying environmental factors that contribute to plant and microbial community variation at different spatial scales can provide critical information for restoration of these communities and the ecosystem services they provide. The objectives of this study were to (i) quantify the relationships among landscape/local environmental factors and plant, bacterial and denitrifier communities, and (ii) assess the spatial relationships between environmental and biological community matrices in 27 restored Illinois wetlands. We hypothesized that plant and microbial community composition are sensitive to different environmental factors operating at local compared to landscape scales. We surveyed plant assemblages, overall bacterial communities, and denitrifying bacteria. Landscape (surrounding land cover, regional climate variables) and local soil factors (soil organic matter, moisture, inorganic nitrogen, pH, redox status) were also assessed. Land use, temperature, and nitrogen availability influenced plant community composition. In contrast, microbial community composition was correlated with local soil factors, especially pH. Our results demonstrated that plant communities in restored wetlands are influenced by both landscape and local factors, whereas microbial communities are more strongly influenced by local soil factors. Choosing restoration sites based on environmental conditions known to support particular plant or microbial communities may enhance recovery of ecosystem services mediated by plants and soil microorganisms.