Historical Fluxes of Toxic Trace Elements in the Salton Sea Basin
Abstract
The Salton Sea is a large terminal saline lake in southern California. It is sustained primarily by agricultural runoff and wastewater discharge. The lake is a net sink for toxic elements and compounds because water loss from it is mainly via evaporation. In addition to increasing salinity, rapid recession of the shoreline of the lake is exposing large areas of contaminant-rich bed. This exposure is a major concern because toxicants, including metals and pesticides, could be mobilized via wind entrainment (dust generation) from the exposed lake bed. However, the cycling and bio-accessibility of these contaminants along with their associated implications for human and environmental health are not well understood. This project uses geochemical data from the analyses of sediment cores and salt crust to model the historical fluxes, bio-accessibility, and depositional environments of toxic trace elements. The depositional environments and flux of trace elements in the lake have changed substantially due to anthropogenic forcing, including flooding and desiccation. For example, the bottom of the northern lobe of the lake has turned increasingly anoxic, while the oxygen level at the bottom of the southern lobe varies seasonally. Conditions at the lake are expected to further deteriorate due to decreasing inflow and associated exposure of the lake bed. Therefore, a full understanding of the cycling and bio-accessibility of contaminants in the lake can be valuable in assessing and mitigating threats to human and environmental health at the Salton Sea basin.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFMGH42A..06O
- Keywords:
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- 0230 Impacts of climate change: human health;
- GEOHEALTH;
- 0232 Impacts of climate change: ecosystem health;
- GEOHEALTH;
- 0240 Public health;
- GEOHEALTH;
- 1615 Biogeochemical cycles;
- processes;
- and modeling;
- GLOBAL CHANGE