Reducing spatial variation in environmental assessment of marine benthic fauna

Abstract

The Benthic Quality Index, BQI, is widely used for benthic quality assessment. Here, we investigated if spatial variation in the BQI can be reduced by accounting for the environmental factors instead of having different boundaries for different salinity regimes between status classes in the EU Water Framework Directive and Marine Strategy Framework Directive. For this purpose we tested salinity, sediment structure, and depth in a regression model to test their contribution to variations in BQI. The spatial variation in BQI was better explained by depth than by salinity or sediment structure. The proposed assessment method uses the residuals from the regression model between BQI and depth. With this method the variance in BQI between samples was reduced by 50% to 75% in the majority of situations. A method to establish the boundary between good and moderate status and how to derive EQR-values according to the WFD is presented.

Keywords

Benthic quality index; BQI; Depth; Marine Strategy Framework Directive; Salinity; Sediment; Water Framework Directive

Published in

Marine Pollution Bulletin
2016, volume: 104, number: 1-2, pages: 129-138

SLU Authors

• Leonardsson, Kjell

  • Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences
    

Associated SLU-program

Coastal and sea areas

Global goals (SDG)

SDG14 Life below water

UKÄ Subject classification

Ecology
Environmental Sciences related to Agriculture and Land-use

Publication identifier

• DOI: https://doi.org/10.1016/j.marpolbul.2016.01.050

Permanent link to this page (URI)

https://res.slu.se/id/publ/79718