Microbial activity monitoring by the Integrated Arctic Earth Observing System (MamSIOS)

Microorganisms, though already integral elements, are likely to play an increasingly important role in the Earth’s climate system (Falkowski et al., 2008) and are known to affect polar
biogeochemical cycles (Larose et al., 2013a). In particular, they play important roles in the
generation and decomposition of climate active gases. However, current climate models do
not take into account the response of microbial activity and their influence in biochemical
cycles (Incorporating microbial processes into climate models, ASM report). To improve the
predictive ability of climate models, it is important to understand the mechanisms by which
microorganisms regulate terrestrial greenhouse gas flux and to determine whether changes
in microbial processes will lead to net positive or negative feedbacks on greenhouse gas
emissions (Singh et al., 2010). This contribution has been particularly overlooked for the
polar regions (Figure 1), where the environment has traditionally been considered too harsh
for significant microbial activity to occur. It has long been considered that any life, if present
at all, was either dormant or functioning sub-optimally, as living organisms have to be well
adapted or highly resistant to extreme cold and desiccation, low nutrient availability and
seasonally variable UV radiation levels in order to survive (Harding et al., 2011; Cameron
et al., 2012; Goordial et al., 2013; Larose et al., 2013a). However, it is now clear that
microbial presence is ubiquitous across the polar regions, and recent research into the
polar aerobiome points toward a potentially dynamic polar microbial community and with
it, the possibility of significant microbial activity within the snowpack (Redeker et al., 2017),
even in the most remote locations (Pearce et al., 2009). Research into the aerobiome has
also demonstrated that microorganisms in aerial fallout may remain both viable and active
(Sattler et al., 2001; Harding et al., 2011). Furthermore, the presence of microbes in remote,
low nutrient, low water, very cold environments such as polar glacial surfaces is now well
established for a number of key sites (Hodson et al., 2008; Larose et al., 2010).