Microbial diversity and population density is positively correlated in New York State freshwater wetlands

Abstract

Increasing anthropogenic activities, particularly those associated with urbanization, have increased ecological strain on near-urban freshwater wetlands. Despite wetlands being ecologically significant environments with key functions like habitat preservation, water quality enhancement, nutrient cycling properties, and regulatory roles in maintaining greenhouse gas budgets, research characterizing the microbial diversity of wetland soils and the impact of urbanization on these communities is not well established. To address this gap, this paper aims to investigate the impact of proximity to population centers on the microbial community and environmental conditions of wetlands. To explore the relationships between human population density and freshwater wetland microbial environments, alpha and beta diversity metrics between urban and rural sites in the state of New York were assessed. Moreover, differential abundance of microbes between sites were quantified, and a correlation analysis between pH, nitrogen content and soil saturation was conducted. We show that richness and evenness are significantly higher in the urban sites compared to the rural sites. In addition, differential analysis revealed an enrichment of taxa such as Spirochaetales and Methanosarcinales at urban and rural sites, respectively. Lastly a positive correlation was observed with soil saturation and pH across genera Aidingimonas, Flavobacterium, and Sphingomonas in Owego, a rural site. These findings are inconsistent with our hypothesis and demonstrate that microbial diversity in urban sites increases compared to rural sites which permits the selection of various taxa. Ultimately, this paper highlights the intricate nature of microbial wetland systems, emphasizing the need for further research into the impact of increased urbanization and population density on native wetland microbial communities and their functionality at an ecological scale.