Abstract
The Salton Sea Basin in California suffers from poor air quality, and an expanding dry lakebed (playa) presents a new potential dust source. In 2017-18, depositing dust was collected approximately monthly at five sites in the Salton Sea Basin and analyzed for total elemental and soluble anion content. These data were analyzed with Positive Matrix Factorization (PMF). The PMF method resolved seven dust sources with distinct compositional markers: Playa (Mg, SO4 2-, Na, Ca, Sr), Colorado Alluvium (U, Ca), Local Alluvium (Al, Fe, Ti), Agricultural Burning (K, PO4 3-), Sea Spray (Na, Cl-, Se), Anthropogenic Trace Metals (Sb, As, Zn, Cd, Pb, Na), and Anthropogenic Copper (Cu). All sources except Local Alluvium are influenced or caused by current or historic anthropogenic activities. PMF attributed 55 to 80% of the measured dust flux to these six sources. The dust fluxes at the site where the playa source was dominant (89 g m-2 yr-1) were less than, but approaching the scale of, those observed at Owens Lake playas in the late 20th century. Playa emissions in the Salton Sea region were most intense during the late spring to early summer and contain high concentrations of evaporite mineral tracers, particularly Mg, Ca, and SO4 2-.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 9378-9388 |
| Number of pages | 11 |
| Journal | Environmental Science and Technology |
| Volume | 53 |
| Issue number | 16 |
| DOIs | |
| State | Published - Aug 20 2019 |
| Externally published | Yes |
Bibliographical note
Funding Information:We would like to thank our funding sources, USDA NIFA- Hatch Accession No. 1015963 (Project No. CA-R-ENS-5072-H) and Accession No. 1005159 (Project No. CA-R-PPA-5093-H), the UCR Office of Research and Economic Development, and the University of California Provost Research Fellowship. A.G. was funded by USDA Fertile Futures, Underrepresented Students Pursuing Agricultural-Related Careers (USPARC), and the Albert Marsh undergraduate research award. T.L. and S.B. acknowledge funding from the Coachella Valley Mountains Conservancy. We would also like to thank the wonderful staff at Boyd Deep Canyon Reserve, Dos Palmas Reserve, Wister Wildlife Area, the University of California Riverside-Palm Desert Campus, and Sonny Bono National Wildlife Refuge for supporting our research and providing access to the sampling sites, David Lyons (Environmental Sciences) for assistance with ion chromatography analysis, Ilkuen Lee for assistance with SEM image collection, and Macon Abernathy for assistance with the XRD pattern collection. The authors gratefully acknowledge the NOAA Air Resources Laboratory (ARL) for the provision of the HYSPLIT transport and dispersion model used in this publication.
Publisher Copyright:
Copyright © 2019 American Chemical Society.
