New Mexico Geological Society Annual Spring Meeting — Abstracts

Uranium (U) contamination commonly results from munitions testing, historical conflicts, industrial processes, and mining. Depleted uranium (DU), a form of U, is less radioactively harmful than natural U but still has mutagenic and toxic properties. While human health concerns related to DU toxicity are well established, effects of DU contamination on microbial communities essential for nutrient cycling are not, thus hindering potential remediation strategies for affected environments. Soil samples were obtained from the EMRTC legacy munitions testing site to determine the impact of DU on arid ecosystems. Five sample sites, including a control, were designated based on predicted DU concentrations and further measured with ICP-MS. The pH and electrical conductivity of the samples were measured while gravimetric analysis was conducted to determine the loss on ignition of organic carbon. Decomposition rates were observed with litter bag incubations, soil water retention was calculated, gas flux measurements for CO2, CH4, N2O were recorded, and soil NO3-/NH4+/PO43- were quantified using spectrophotometric analysis. These parameters give an overall glimpse into the microbial metabolic activity in DU landscapes. Preliminary results indicate a negative correlation between DU concentrations and levels of general soil nitrate, water, and organic carbon. Our poster will report gas flux data from the duration of the lab experiment and a complete statistical analysis of all data collected. Our conclusions provide valuable insights for plant-microbial-based DU remediation strategies with applications for uranium-contaminated areas in New Mexico.