rover_tracks_mars

Photo credit: AGU

The best thing that I saw at the AGU 2016 Fall Meeting was the Sagan Lecture by Nathalie Cabrol entitled, “The co-evolution of life and environment and the astrobiological quest.” Like many earth scientists, I often fantasize about applying my current research extreme environments and even to other planets; asking what was the carbon cycle like on a living Mars and how might that organic material have been preserved? But what should we be looking for?

Nathalie’s talk was about asking what type of microbial life inhabited Mars based on past Martian environmental conditions, where on Mars that life might have been active, how long this life was active on the Martian surface, and where might that life have gone when Mars became increasingly uninhabitable (deeper into the subsurface?). The last three questions would point to the places that future missions should go in search of life.

As the role of microbes in carbon cycling in soils including its necromass input of organic matter to soils becomes increasingly important on Earth, this talk inspired me to think more about how environmental/physical stress might affect both necromass production and the physical and chemical stabilization of necromass in the soil.

~Liz Williams