Description

Wetland habitats have a unique combination of characteristics including high nutrients and shallow, brackish water, that allows them to support a number of sensitive organisms. Many estuarine ecosystems are now suffering due to anthropogenic activities and major economic growth. Heavy metals have a number of impacts on estuarine ecosystems including toxicity when found in high enough concentrations. Due to their impact on local species, heavy metal concentrations can provide valuable insight as to the health of the ecosystem. This study aims to determine the abundance and spatial distribution of heavy metals in the Tijuana River Estuary system. We collected sediment samples in the Tijuana River Estuary in July 2017 using a transect method in the south, east, and western areas of the estuary. Additional transects were collected when possible. We collected and analyzed a total of 69 sediment samples using an X-Ray fluorescence (XRF) machine to determine the abundance of six metals known to influence the health of estuarine environments: nickel, arsenic, lead, mercury, copper, and zinc. The metal concentrations were then spatially analyzed in ArcGIS 10.4. Heavy metal particles tend to attach to fine sediment particles, so it was hypothesized that concentrations would be highest in the floodplain where the finest sediment particles settle. The results of the study supported our hypothesis that concentrations would be highest in the floodplain, and several metals were found at levels that exceed EPA regulatory standards.

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Concentration of Heavy Metals in Tijuana River Estuary Sediment

Wetland habitats have a unique combination of characteristics including high nutrients and shallow, brackish water, that allows them to support a number of sensitive organisms. Many estuarine ecosystems are now suffering due to anthropogenic activities and major economic growth. Heavy metals have a number of impacts on estuarine ecosystems including toxicity when found in high enough concentrations. Due to their impact on local species, heavy metal concentrations can provide valuable insight as to the health of the ecosystem. This study aims to determine the abundance and spatial distribution of heavy metals in the Tijuana River Estuary system. We collected sediment samples in the Tijuana River Estuary in July 2017 using a transect method in the south, east, and western areas of the estuary. Additional transects were collected when possible. We collected and analyzed a total of 69 sediment samples using an X-Ray fluorescence (XRF) machine to determine the abundance of six metals known to influence the health of estuarine environments: nickel, arsenic, lead, mercury, copper, and zinc. The metal concentrations were then spatially analyzed in ArcGIS 10.4. Heavy metal particles tend to attach to fine sediment particles, so it was hypothesized that concentrations would be highest in the floodplain where the finest sediment particles settle. The results of the study supported our hypothesis that concentrations would be highest in the floodplain, and several metals were found at levels that exceed EPA regulatory standards.

 

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