The Water Framework Directive (WFD) requires the ecology of River Basin Catchments to be assessed to determine where action is needed to improve the water environment. Benthic invertebrates are one of five biological quality elements to be assessed under the WFD. They are an important component of marine ecological systems and are effective indicators of certain types of disturbance or ‘pressure’. They complement the other WFD biological quality elements for transitional and coastal surface waters; angiosperms (flowering plants), fish, macroalgae and phytoplankton.
This report describes the development of the method for assessing the ecological status of the macrobenthic invertebrates of sediment habitats in coastal and transitional (estuarine) water bodies for the first River Basin Management Plans (RBMPs) under the WFD for the United Kingdom (UK) and the Republic of Ireland (ROI).
The method is named the Infaunal Quality Index (IQI).