Microbial Communities in Chesapeake & Ohio Canal National Historical Park and Their Function as Indicators of Water Quality

Abstract

The objective of this study was to establish meaningful relationships between prokaryotic community profiles and water quality parameters in different water bodies (spring, stream, cave, and mine) in the middle reach of the Chesapeake & Ohio Canal National Historic Park (C&O), Maryland. The microbial profiles in the water samples were determined using metagenomic analysis. The relationships between microbial phylogenetic profiles and water quality parameters were investigated using principal component analysis (PCA) and redundancy analysis (RDA). The most abundant phyla identified in most samples were Proteobacteria (55.4%), Bacteroidetes (12.3%), Actinobacteria (10.6%), Firmicutes (2.4%), Planktomycetes (1.8%), Verrucomicrobia (1.5%), Chloroflexi (1.5%), and Acidobacteria (1.3%), which are major bacterial and archaeal groups typically observed in natural freshwater environments. PCA showed that water chemistry was determined primarily by the geology of the site and the type of water source (i.e., spring, stream, cave, or mine). Most samples located in carbonate formations correlated with high alkalinity, inorganic carbon, and calcium, representing the typical karstic geochemistry. RDA shows that pH, electrical conductivity, temperature and nutrients including nitrate, phosphate, and sulfate, were significant determinants of the microbial ecology.

Keywords:

• Microbial ecology
• karst water
• metagenomics
• microbial diversity
• springs
• caves

Acknowledgments

The following students provided field, laboratory and mapping support: John Tudek, Katie McConahy, Habib Bravo-Ruiz, Jill Riddell, and Kyle Lee. We also would like to thank the staff and interns at the Chesapeake and Ohio Canal National Historical Park.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This project was funded by the National Park Service via Task Agreement Number P11AC60552 with the Great Lakes Northern Forest Cooperative Ecosystem Studies Unit (cooperative agreement H6000082000).