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Using Associations Between Biological Field Data and Ambient Water Chemistry Data to Derive Water Quality Targets
Edward T .Rankin
Center for Applied Bioassessment and Biocriteria
P.O. Box 21541
Columbus, Ohio 43221-0541
One of the many benefits of a strong state monitoring program is the amassing of large data sets with biological attributes paired with environmental stressor data. Such datasets allow powerful retrospective analyses that can be combined with controlled laboratory data to help explain the effects of stressors on environmental impairment and threats that are observed in nature. Ohio has such a dataset that extends back at least 25 years with consistently collected water chemistry data, habitat data, and fish and macroinvertebrate community data. In this presentation I will provide examples of how this data set was used to: 1.) help derive tiered ammonia and dissolved oxygen criteria for Ohio's WQS, 2.) explain patterns and derive targets for the effects of nutrients on aquatic life, 3.) create "caps" on dissolved metals translators based on biological associations with total recoverable metals, and 4.) derive background concentrations for most commonly monitored chemicals in Ohio to aid in interpreting cause/source assessments in watershed intensive surveys. I will also discuss recent work exploring relationships between sulfates, chlorides and macroinvertebrate taxa abundance. Such associations can be used to rank individual taxa sensitivities to water chemistry variables and compared to "general" taxa or species tolerance measures used in community indices.