Benthic Response Index

Benthic communities are widely used in the monitoring of effects of marine pollution as the organisms are mostly sessile and integrate effects of pollutants over time. Most benthic communities comprise a large number of species and because of the varying sensitivities of species it should be possible to identify subtle effects of pollutants reflected in changes in community structure. The benthic response index (BRI) is a multivariate index that measures the abundance-weighted average pollution tolerance of species occurring in a sample, and is comparable to the weighted average approach that is used in gradient analysis. Quantitative application throughout the southern California coastal shelf environment was undertaken that measures the conditions of a benthic communities, with levels of environmental disturbance defined by identified thresholds. The index values, at which key community attributes were lost, were established with four response levels. The use of BRI has been compared to the infaunal trophic index (ITI), an index extensively used in the southern California area. © 2008 Elsevier B.V. All rights reserved.