TY - JOUR
T1 - Subglacial erosion has the potential to sustain microbial processes in Subglacial Lake Whillans, Antarctica
AU - Gill-Olivas, Beatriz
AU - Telling, Jon
AU - Tranter, Martyn
AU - Skidmore, Mark
AU - Christner, Brent
AU - O'Doherty, Simon
AU - Priscu, John
PY - 2021/12/1
Y1 - 2021/12/1
N2 - Subglacial Lake Whillans lies below around 800 m of Antarctic ice and is isolated from fresh sources of photosynthetic organic matter to sustain life. The diverse microbial ecosystems within the lake and underlying sediments are therefore dependent on a combination of relict, overridden, marine-derived organic matter and mineral-derived energy. Here, we conduct experiments to replicate subglacial erosion involving both gentle and high-energy crushing of Subglacial Lake Whillans sediments and the subsequent addition of anoxic water. We find that substantial quantities of reduced species, including hydrogen, methane, acetate and ammonium and oxidised species such as hydrogen peroxide, sulfate and carbon dioxide are released. We propose that the concomitant presence of both hydrogen and hydrogen peroxide, alongside high concentrations of mineral surface radicals, suggests that the splitting of water on freshly abraded mineral surfaces increases the concentrations of redox pairs from rock-water reactions and could provide a mechanism to augment the energy available to microbial ecosystems.
AB - Subglacial Lake Whillans lies below around 800 m of Antarctic ice and is isolated from fresh sources of photosynthetic organic matter to sustain life. The diverse microbial ecosystems within the lake and underlying sediments are therefore dependent on a combination of relict, overridden, marine-derived organic matter and mineral-derived energy. Here, we conduct experiments to replicate subglacial erosion involving both gentle and high-energy crushing of Subglacial Lake Whillans sediments and the subsequent addition of anoxic water. We find that substantial quantities of reduced species, including hydrogen, methane, acetate and ammonium and oxidised species such as hydrogen peroxide, sulfate and carbon dioxide are released. We propose that the concomitant presence of both hydrogen and hydrogen peroxide, alongside high concentrations of mineral surface radicals, suggests that the splitting of water on freshly abraded mineral surfaces increases the concentrations of redox pairs from rock-water reactions and could provide a mechanism to augment the energy available to microbial ecosystems.
U2 - 10.1038/s43247-021-00202-x
DO - 10.1038/s43247-021-00202-x
M3 - Article (Academic Journal)
SN - 2662-4435
VL - 2
SP - 134
JO - Communications Earth & Environment
JF - Communications Earth & Environment
IS - 1
ER -