GLP

Ecosystem Diagnostics

Ecosystem Diagnostics

Waterborne is part of a consortium of companies and institutes who are examining the relative impact of stress factors, including chemical mixtures, to river systems by developing and using statistical and eco-epidemiological methodologies.

Prospective risk assessments of chemicals may include the use of bioavailability models, Species Sensitivity Distributions and mixture-effect modeling to estimate the proportion of species potentially affected by chemical mixtures. To test such approaches, it is imperative that datasets be obtained that contain a range of prospective risks from chemicals and other stressors which can be matched to documented biological impacts using a geographic information system.

Since species assemblages can be affected by factors other than chemicals, an eco-epidemiological analysis of chemical risks needs to take into account the myriad of potential factors that may affect biological community status. These factors include instream habitat quality, ecoregion, river size, and water chemistry. Characteristics of biological assemblage (traits) may also be helpful in diagnosing potential causation of impacts.

The presentations listed below (from SETAC-Europe 2010) provide information on the assemblage of perhaps one of the largest datasets collected to date. The dataset covers more than 2000 georeferenced sites from the state of Ohio and includes:

land use (agriculture, forest, urban, presence of livestock)
soil condition (organic carbon, erosivity)
presence of septic systems and wastewater exposure
predicted chemical risks from nonpoint sources and point sources as well as instream metals and ammonia
instream habitat and aquatic community status (fish and macroinvertebrates)

Diverse statistical and modeling methods were applied to the dataset including regression trees, neural-networks, weights of evidence/weighted linear regression, general linear models, and food-web modeling methods. The outcomes of the analyses provide crucial information for deriving effective river basin and chemical management plans.

Presentations from the SETAC Europe 20th Annual Meeting
May 23-27, 2010, Seville, Spain

Ecosystem Diagnostics Poster Corner at SETAC Adobe Acrobat is required to view the presentations listed below. A free version of Acrobat is available from Adobe.