Leachable trace elements in San Francisco bay sediments: Indicators of sources and estuarine processes |
| |
Authors: | Andrew Eaton |
| |
Institution: | (1) Chesapeake Bay Institute, Johns Hopkins University, 21218 Baltimore, Maryland, USA |
| |
Abstract: | Geographic variations of leachable Fe, Mn, Cu, Zn, Co, and Ni in San Francisco Bay sediments indicate that Fe, Mn, Co, and
Ni are all predominantly supplied to bay sediments from the San Joaquin-Sacramento River system, with little evidence for
direct contributions from municipal and industrial sources. In contrast, both Cu and Zn have significant sources within the
Bay system, probably municipal and industrial discharges.
Precipitation and coagulation of Fe oxides in the low-salinity region of the estuary results in significantly greater concentrations
of that element in the most landward portion of the estuary. Co and Ni appear to be actively coprecipitating with Fe but their
distributions are also influenced by other factors. Mn is not a major geochemical agent in this system. Its pattern is different
from the other elements and it does not account for any of the other elemental variance. The behavior of Cu and Zn is affected
not only by the presence of nonriverine sources but also through surface-active processes and organic complexing, coupled
with the transportation of fine-grained sediment. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|