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James River CHLa Study Data Analysis Workgroup. Question: Are our current CHLa criteria protective of aquatic life? To answer this question, we will use multiple lines of evidence including literature review and bioassay results from the present study.
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James River CHLa Study Data Analysis Workgroup • Question: Are our current CHLa criteria protective of aquatic life? • To answer this question, we will use multiple lines of evidence including literature review and bioassay results from the present study. • This presentation is a summary of lit review findings and bioassay results.
What’s included in this summary? • Studies showing effects from exposure to 5 algal species of concern in the lower James • Some of Kim’s bioassay results • Inclusion was limited to • bioassays using live cell cultures (i.e. did not include lysate or toxin assays) or bloom samples • Results with > 20% effect on test organism • Results were significantly different from control • Lab results (did not include ambient findings of fish kills)
Mortality from exposure to < 10K cells/ml C. polykrikoides • Many variables within the studies: • Algal strain • Test organism and age of organism • Type of study (bloom, mono-culture, lysate, toxin) • Stage of culture • Proportion of bloom that is algal species of interest
Other algal species of concern in lower JR: Alexandrium monilatum, Karlodinium veneficum,Scrippsiella trochoidea, Prorocentrum minimum
Other algal species of concern in lower JR: Alexandrium monilatum, Karlodinium veneficum,Scrippsiella trochoidea, Prorocentrum minimum blue = Karlodinium, red = Alexandrium, Green = Scrippsiella, purple = Prorocentrum
Mortality effects blue = Karlodinium, red = Alexandrium, Green = Scrippsiella, purple = Prorocentrum
Mortality effects from exposure to < 70K cells/ml blue = Karlodinium, red = Alexandrium, Green = Scrippsiella, purple = Prorocentrum Karlodinium and Alexandrium not as abundant in JR as Cochlodinium but do have toxic effects Kim doing additional work this summer with both species as well as with blooms
Microcystis aeruginosa 100% mortality in 96 h • James River cell concentrations: • < 10K fixed station monitoring in last 3 years • VIMS has observed concentrations up to 2.2M at ConMon sites in 2013
Microcystis aeruginosa Red = mortality; blue = decreased growth; green = decreased fecundity