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Full-Text Articles in Environmental Sciences
Assessing Ecosystem Health Through Contaminants In The Tijuana River National Estuarine Research Reserve, Nancy Torres
Assessing Ecosystem Health Through Contaminants In The Tijuana River National Estuarine Research Reserve, Nancy Torres
Theses
Although the Tijuana River Estuary (TRE) remains the largest, most-intact coastal wetland in Southern California, it has a history of major changes, much of this related to its location immediately north of the US / Mexico Border. One of the primary challenges is cross-border flows from the rapidly growing city of Tijuana, Baja California, Mexico, and the delivery of wastewater, debris, and sediment to sensitive coastal wetland ecosystems. There is a need to more fully investigate these environmental changes to assess the ecosystem health of the Tijuana River Estuary over time, especially related to pollution impacts. This can inform an …
Coastal Watershed Monitoring And Management: Geomorphology, Geochemistry, And Hydrologic Modeling Of Los Peñasquitos Creek, Ca, Ravleen Khalsa-Basra
Coastal Watershed Monitoring And Management: Geomorphology, Geochemistry, And Hydrologic Modeling Of Los Peñasquitos Creek, Ca, Ravleen Khalsa-Basra
Theses
Rivers in semi-arid climates are directly influenced by local geographic and hydrologic conditions and impacted by modifications to hydrology via urbanization. Changes can influence erosion, morphology, habitat sustainability, and watershed health. In highly urbanized southern California coastal regions, these rare open spaces provide vital ecosystem services. Los Peñasquitos Creek in San Diego County is one such watershed. Using stream surveying and laboratory methods we quantified channel characteristics, grain size distribution, total metal concentration [M], organic carbon (%OC), and phosphate to longitudinally characterize the creek for improved management. Results identified three distinct reaches in the watershed (upper, middle, lower). Downstream, depth …
Artisanal Mining Impacts In Urbanized Semi-Arid Environments: Lessons From Historic Arsenic Mining Near San Diego, California, James A. Wright
Artisanal Mining Impacts In Urbanized Semi-Arid Environments: Lessons From Historic Arsenic Mining Near San Diego, California, James A. Wright
Theses
Anomalously elevated arsenic concentrations occur at an abandoned artisanal mine site in an open space recreational park in urban San Diego County, California. Although mining at the site ceased 100 years ago little to no remediation efforts took place leaving shafts, adits, waste piles and derelict infrastructure accessible by inquisitive hikers and adventurers frequenting Black Mountain Open Space Park. This study evaluates the geochemical mechanisms of As transport downgradient from the mine and examines the contribution of both climate and urbanization on the restriction of As mobility. Sediment As concentrations reach 2,320 mg/kg (483 times background crustal concentrations; n=73) along …