MP3 Chronic and Sublethal Sediment Toxicity
254 Portland Ballroom
1:20 PM - 4:40 PM, Monday
() Macrobenthic responses to natural and contaminant related variables in Mugu Lagoon, a tidal wetland in Southern California.
Anghera, M1, Ambrose, R1, 2, 1 Department of Environmental Health Sciences2 Envrionmental Sciences and Engineering, University of California Los Angeles
ABSTRACT- We examined the effects of pollutants on the benthic infaunal communities in a coastal wetland that has received contaminants from military and agricultural activities. Sediment contaminant, sediment toxicity, and bethic community structure were assessed in two salt marsh tidal creeks and a mudflat. We used a synoptic approach to link benthic community abundance patterns to natural environmental variables (sediment size, organic content, porewater ammonia, pH, and dissolved oxygen) and contaminant related variables (metal and organic pollutants and amphipod toxicity). Infaunal and environmental factors were examined using non-metric multidimensional scaling (MDS) and Principle Component Analysis (PCA) to distinguish benthic responses to natural and contaminant related factors. In tidal creeks the benthic community responded to contaminants while in the mudflat contaminant related impacts could not be found. The lack of relationships between macrobenthic community patterns and environmental variables may be due to unmeasured contaminants or an insensitive benthos.
Key words: amphipod toxicity, Sediment Quality Triad, contaminant related impacts, wetlands