Nutrient and population dynamics in a subglacial reservoir: a simulation case study of the Blood Falls ecosystem with implications for astrobiology

Abstract Subglacial ecosystems have recently become of interest within the astrobiological community, as they represent a potentially habitable location in otherwise uninhabitable environments. We used data from Blood Falls, particularly the periodic discharge from the subglacial reservoir beneath T...

Full description

Bibliographic Details
Published in:International Journal of Astrobiology
Main Authors: Fisher, Thomson Mason, Schulze-Makuch, Dirk
Format: Article in Journal/Newspaper
Language:English
Published: Cambridge University Press (CUP) 2013
Subjects:
Online Access:http://dx.doi.org/10.1017/s147355041300013x
https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S147355041300013X
Description
Summary:Abstract Subglacial ecosystems have recently become of interest within the astrobiological community, as they represent a potentially habitable location in otherwise uninhabitable environments. We used data from Blood Falls, particularly the periodic discharge from the subglacial reservoir beneath Taylor Glacier, Antarctica, to construct an ecosystem model of the putative subglacial microbial community residing there using system dynamics modelling. The model results were, for the most part, within an order of magnitude of the geochemical field data. Productivity was quite low, at 6.4×10 −5 g carbon l −1 yr −1 . Based on the results, we draw the following conjectures for the search for life on Mars: A similar ecosystem would require a continual supply of oxidized iron for energy and generate significant amounts of reduced iron as a waste product, be relatively resilient to temporary disturbances, and, thermodynamically, would require at least 0.003 kJ mol l −1 of energy to survive at that level of productivity. These results may help to better identify the constraints and boundaries of ecosystems in extreme environments, on Earth and other planetary bodies.