Microbial communities in UK aquifers: current understanding and future research needs

Abstract

The presence and activity of microorganisms in aquifers can affect, amongst other things, nutrient cycling, contaminant degradation and water flow. The introduction of a pollutant or other changes in water chemistry can alter the microbial community composition and affect aquifer functioning. To understand the microbial response to anthropogenically induced changes, a better knowledge of baseline microbial communities in uncontaminated aquifers is needed. Here, we review the information on microorganisms in UK aquifers together with examples of research from other countries on this topic, and discuss how these communities might respond to disturbance. Research into microbial communities in UK aquifers has mostly been limited to bacteria and often reveals a community dominated by Proteobacteria. The community composition is influenced by factors such as mineralogy and water chemistry, and the natural baseline community may be altered by aquifer contamination. A UK-wide survey of aquifer microbes, similar to one recently carried out in New Zealand, would provide valuable information about the current state of UK aquifer microbiology. This would lead to a greatly improved understanding of the ecosystem services provided by the microbial communities present in aquifers, allow future monitoring and assessment of the effects of pollution, and assist in groundwater resource management.

Groundwater flooding: Ecosystem structure following an extreme recharge event

“…Ecological assessment of groundwater is a very recent discipline (see reviews by Danielopol et al, 2003;Gregory et al, 2014;Steube et al, 2009).…”

Diversity and predictive metabolic pathways of the prokaryotic microbial community along a groundwater salinity gradient of the Pearl River Delta, China

“…In addition, some types of clones, which correlated with aerobic microbial groups, such as Exiguobacterium , Pseudomonas and Acinetobacter , were revealed in all the groundwater samples with a relatively high yield. In addition, 40 of the top 50 genera were present in all the groundwater samples, which may reflect the ecological coherence of municipal groundwater ecosystems 43 .…”

Linkage Between Dissolved Organic Matter Transformation, Bacterial Carbon Production, and Diversity in a Shallow Oligotrophic Aquifer: Results From Flow-Through Sediment Microcosm Experiments

“…The dominating groups of bacteria found in our aquifer sediments were in accordance of what is known from other groundwater ecosystem studies. A dominance of Proteobacteria was regularly reported (Shi et al, 1999;Detmers et al, 2004;Hendrickx et al, 2005;Boyd et al, 2007;Griebler and Lueders, 2009;Flynn et al, 2012;Gregory et al, 2014;Sirisena et al, 2018). Besides Proteobacteria, Actinobacteria, Firmicutes, Bacteriodetes, and Nitrospirae have frequently been detected at relevant abundances (Hendrickx et al, 2005;Griebler and Lueders, 2009;Zhou et al, 2012;Navarro-Noya et al, 2013;Gregory et al, 2014;Nowak et al, 2017;Bellini et al, 2018;Savio et al, 2018;Smith et al, 2018).…”