Nitrogen Cycling and Biosignatures in a Hyperarid Mars Analog Environment.

ABSTRACT: The hyperarid Atacama Desert is a unique Mars-analog environment with a large near-surface soil nitrate reservoir due to the lack of rainfall leaching for millennia. We investigated nitrogen (N) cycling and organic matter dynamics in this nitrate-rich terrestrial environment by analyzing the concentrations and isotopic compositions of nitrate, organic C, and organic N, coupled with microbial pathway-enzyme inferences, across a naturally occurring rainfall gradient. Nitrate deposits in sites with an annual precipitation of <10 mm carry atmospheric δ¹⁵N, δ¹⁸O, and Δ¹⁷O signatures, while these values are overprinted by biological cycling in sites with >15 mm annual precipitation. Metagenomic analyses suggest that the Atacama Desert harbors a unique biological

SUBMITTER: Shen J 

PROVIDER: S-EPMC8861911 | biostudies-literature | 2022 Feb

REPOSITORIES: biostudies-literature