Abstract Title

Session S-03A: Changes in Salish Sea Water Quality

Keywords

Marine Water Quality

Location

Room 615-616-617

Start Date

30-4-2014 3:30 PM

End Date

30-4-2014 5:00 PM

Description

Benthic foraminifera, shelled protists, are valuable tools for monitoring environmental conditions of the sediment surface in nearshore marine and estuarine to marsh settings. This study analyzed 64 sediment samples from Bellingham Bay (June 1997, 2006 and 2010) and 18 samples from Boundary Bay, Birch Bay and Neptune Beach (June 2006 and 2010), provided by the Washington State Department of Ecology. Thirty five taxa were identified, dominated by three calcareous and one agglutinate species. In Bellingham Bay, benthic foraminiferal diversity and density deteriorated strikingly between 1996 and 2006, most notably in the middle of the bay. Many of these bay-center sites yielded no foraminifera at all, and the situation did not improve in 2010. The samples from Boundary Bay to Neptune Beach generally demonstrated higher diversity; however decreases in both diversity and density are also recorded from 1996 to 2006. Correlations with six metal contaminants and with total polycyclic aromatic hydrocarbons showed a negative trend but R2 values are low. This corroborates the findings from benthic invertebrate faunas from the same sites by Weakland et al. (2013). Bottom water dissolved oxygen levels and pH data from the central part of Bellingham Bay indicate hypoxia and high levels of acidification. We infer that either combinations of organic pollutants or eutrophication have impacted the benthic biota.

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Apr 30th, 3:30 PM Apr 30th, 5:00 PM

Rapid deterioration of sediment surface ecosystems in Bellingham Bay as indicated by benthic foraminifera

Room 615-616-617

Benthic foraminifera, shelled protists, are valuable tools for monitoring environmental conditions of the sediment surface in nearshore marine and estuarine to marsh settings. This study analyzed 64 sediment samples from Bellingham Bay (June 1997, 2006 and 2010) and 18 samples from Boundary Bay, Birch Bay and Neptune Beach (June 2006 and 2010), provided by the Washington State Department of Ecology. Thirty five taxa were identified, dominated by three calcareous and one agglutinate species. In Bellingham Bay, benthic foraminiferal diversity and density deteriorated strikingly between 1996 and 2006, most notably in the middle of the bay. Many of these bay-center sites yielded no foraminifera at all, and the situation did not improve in 2010. The samples from Boundary Bay to Neptune Beach generally demonstrated higher diversity; however decreases in both diversity and density are also recorded from 1996 to 2006. Correlations with six metal contaminants and with total polycyclic aromatic hydrocarbons showed a negative trend but R2 values are low. This corroborates the findings from benthic invertebrate faunas from the same sites by Weakland et al. (2013). Bottom water dissolved oxygen levels and pH data from the central part of Bellingham Bay indicate hypoxia and high levels of acidification. We infer that either combinations of organic pollutants or eutrophication have impacted the benthic biota.