Abstract and subjects
Microbial processes are critical to groundwater quality and overall ecosystem functioning as microorganisms are essential to biogeochemical cycling and biodegradation of contaminants. This book chapter describes the key microbiological processes found in both natural and contaminated groundwater ecosystems, microorganisms that have been identified as controlling these processes, and how human activities have influenced groundwater microbial communities. We further highlight some future research directions including the effects of climate change on groundwater microbial communities, the spatial and temporal dynamics of microbial communities, and how bioaugmentation of groundwater communities could improve groundwater quality. Additionally, we describe some recent technological advances that assess in situ microbial activity, which we expect will greatly advance research into the effect of environmental fluctuations and human activities on low biomass groundwater microbial communities.