Microbial Activity and Diversity Vary with Plant Diversity and Biomass in Wetland Ecosystems

Wetland ecosystems have low plant diversity, dominated only by one or two types of vegetation. Species with high biomass can easily invade wetlands and the effect of plant invasion on ecosystem process rates has drawn considerable attention within the field of microbial ecology. However, the effects of high biomass plants on microbes, which play a central role in wetland biogeochemistry, are notably understudied. This study investigates the relationship between plant species and their enzyme activities with microbial diversity in wetland ecosystems. Samples were collected from both natural and constructed wetlands to test whether high and low biomass species of submerged aquatic plants would have significant effects on microbial activity and diversity. This study found that plant species with high biomass increased activities of hydrolase activities such as beta-glucosidase and N-acetyl-glucosaminidase. Microbial diversity was higher in rhizosphere with two high biomass plant species present compared to one plant species, due to niche competition, as indicated by a higher Shannon-Weaver index value.