Serpentinite-hosted ecosystems: Life in extreme environments
By Jennifer Zwicker, Department of Geodynamics and Sedimentology, University of Vienna.
All life on Earth requires energy, most of which comes from the sun and is processed by photosynthesis. However, there is an alternative energy source for life that stems from the Earth's interior. This chemical energy can be fostered by life that depends on chemosynthesis. Chemical energy is generated at mid ocean ridges and at ancient seafloor rocks on land, where they undergo chemical alteration summarized as serpentinization. These reactions produce hydrogen and methane that can be utilized as an energy source for microbial life, making these systems a strong candidate for the origin of life on Earth and, possibly, on other planets. It is widely accepted that methane is produced abiotically in serpentinite-hosted systems. However, recent investigations suggest that this view might have to be reconsidered. This project elucidates the role of microorganisms in carbon cycling in onshore serpentinite-hosted ecosystems in an attempt to demonstrate how methanogeic archaea may contribute to methane emissions from the geosphere to the atmosphere.