Dissolved Organic Matter in Serpentinization-Influenced Groundwater: Fingerprints of Deep and Shallow Sources
EMSL Project ID
49107
Abstract
The aim of this study is to provide a detailed description of the composition and the quantity of dissolved organic matter in serpentinite-hosted groundwaters, capitalizing upon a well-studied microbial observatory in the Coast Range Ophiolite near Lower Lake, CA. Serpentinization-influenced groundwaters contain inputs from circulating soil-derived organic matter, in situ production by chemolithoautotrophs, and abiogenically-derived methane and small organic molecules associated with water-rock reactions. We will conduct measurements of natural dissolved organic matter (DOM) in groundwater systems at various depths to develop a profile of organic compounds at the site. In parallel we will analyze soluble metabolites produced by microbial cultures from the site to constrain the identity and source of the groundwater DOM. The proposed work builds upon an extensive database of microbiological, geochemical, and hydrological information from the site, produced, in part through a previous JGI CSP. The new work will mechanistically explore the relationships between microbial activities and groundwater DOM composition, and the impacts of these activities upon carbon cycling and greenhouse gas flux in serpentinite environments. EMSL contains unique analytical capabilities and expertise for characterizing DOM in complex groundwater systems. These resources will prove valuable in the context of challenging serpentinization-influenced ecosystems, impacted by high pH, low biomass, and multiple carbon sources and sinks.
Project Details
Project type
Exploratory Research
Start Date
2015-11-01
End Date
2016-09-30
Status
Closed
Released Data Link
Team
Principal Investigator