New published research by scientists at the National Centers for Coastal Science demonstrates an improved approach for calculating and comparing bioeffects levels in different places. Using a single numerical score, rather than the traditional system based on three distinct data sets (benthic community structure, sediment contamination, and sediment toxicity, known as the sediment quality triad) the new system allows an “apples to apples” comparison of contamination that should help managers identify hot spots and target remediation dollars.
The standard method of determining how well a habitat is doing depends on whether or not each of three data sets are at the same scale. If all agree, this test works well, but that often doesn’t happen so you’re left with a squishy interpretation at best. This experimental approach normalizes all the data to the same scale, plots it on triangular axes, calculates the area, and uses that number as a single metric.
The researchers also discovered that the new method can help distinguish the source of environmental degradation in an area, whether due to contaminants, hypoxia, or other stressors.
This method was developed using data from the Chesapeake Bay and has been applied successfully to other locations including Delaware, Galveston, and Biscayne Bays.
Citation: Hartwell, S. Ian, M. J. Hameedi, and A. S. Pait. 2011. Empirical assessment of incorporating sediment quality triad data into a single index to distinguish dominant stressors between sites. Environmental Monitoring and Assessment (2011) 174: 605 -623. doi 10.1007/s10661-010-1482-8