Pore Water as an Indicator of Metal Mobility in San Francisco Bay
Poster Number
11
Format
Poster Presentation
Faculty Mentor Name
Laura Rademacher
Faculty Mentor Department
Earth and Environmental Sciences
Abstract/Artist Statement
The environmental conditions at the sediment - water interface play an important role in metal mobility in urban watersheds. For example, the mobility of iron depends on whether oxygen is present. Conditions in the surface sediment of lakes and streams can influence the oxygen levels of overlying waters, and therefore, pollutant mobility in the lakes. Three reservoir-watershed systems in the San Francisco Bay area were studied to better understand the geochemical relationship between sediment and overlying water. The reservoirs selected were Lake Aliso, Lake Anza, and Don Castro Lake, each having unique influencing variables. Lake Aliso is impacted by acid mine drainage, while Lake Anza is relatively isolated from anthropogenic impact, and Don Castro Lake is located near urban area and development. Sediment and water samples were collected from the lake bottom, inlet, and outlet at each site to examine variables of associated waters to test the relationship between environmental conditions at the sediment-water interface and the potential for metal mobility in surface waters. During March and April 2015, samples were collected from each of the sites. First, in the field, we isolated and removed water that was located in the pore spaces of the first two inches of soil. This process allowed us to solely remove water that was located in the pore of the sediment and reduce the influence of other variables. The second part consisted of lab work that processed the water and compared it to the variables of water in the column and sediment. Examining variables such as: temperature, pH, conductivity, dissolved oxygen, discharge, alkalinity, as well as physical descriptions of the sediment revealed there to be a relationship.
Location
DeRosa University Center, Ballroom
Start Date
25-4-2015 10:00 AM
End Date
25-4-2015 12:00 PM
Pore Water as an Indicator of Metal Mobility in San Francisco Bay
DeRosa University Center, Ballroom
The environmental conditions at the sediment - water interface play an important role in metal mobility in urban watersheds. For example, the mobility of iron depends on whether oxygen is present. Conditions in the surface sediment of lakes and streams can influence the oxygen levels of overlying waters, and therefore, pollutant mobility in the lakes. Three reservoir-watershed systems in the San Francisco Bay area were studied to better understand the geochemical relationship between sediment and overlying water. The reservoirs selected were Lake Aliso, Lake Anza, and Don Castro Lake, each having unique influencing variables. Lake Aliso is impacted by acid mine drainage, while Lake Anza is relatively isolated from anthropogenic impact, and Don Castro Lake is located near urban area and development. Sediment and water samples were collected from the lake bottom, inlet, and outlet at each site to examine variables of associated waters to test the relationship between environmental conditions at the sediment-water interface and the potential for metal mobility in surface waters. During March and April 2015, samples were collected from each of the sites. First, in the field, we isolated and removed water that was located in the pore spaces of the first two inches of soil. This process allowed us to solely remove water that was located in the pore of the sediment and reduce the influence of other variables. The second part consisted of lab work that processed the water and compared it to the variables of water in the column and sediment. Examining variables such as: temperature, pH, conductivity, dissolved oxygen, discharge, alkalinity, as well as physical descriptions of the sediment revealed there to be a relationship.