Biological benthic tools as indicators of coastal marine ecosystems health

Abstract

Coastal marine ecosystems are increasingly subjected to environmental stress and degradation due to pollution. Several research programmes have addressed this problem and produced relevant data sets for specific areas, often including consistent sets of environmental and biological variables. The value of existing information gathered from these types of data can be largely increased by combining them into a common data set to determine globally applicable relationships. To perform this exercise, the Intergovernmental Oceanographic Commission (IOC) of UNESCO has recently formed the Ad hoc Study Group on Benthic Indicators (http://www.ioc.unesco.org/benthicindicators) with the aim of developing robust indicators of benthic health. In this paper, initial products and ongoing activities of this international initiative are described and discussed. An expansion of initial IOC/UNESCO research on benthic fauna-organic carbon relationships is also presented. As part of this follow-up research, the relationship between total organic carbon concentrations of sediment and abundance, biomass and species diversity of benthic macrofauna was evaluated using data sets from 2 different regions of the world comprising 3 different coastal marine environments. The ability of identifying threshold levels in selected variables that could serve as indicators of related adverse environmental conditions leading to stress in the benthos is envisaged within the frame of a larger joint analysis, carried out by the IOC/UNESCO Study Group on Benthic Indicators, of merged data sets from several coastal regions worldwide.

Keywords:

• Benthic macrofauna
• Total organic carbon
• Biodiversity
• Bioindicators
• Sediments

Acknowledgement

This work was prepared within the frame of the EC project MAMA – Mediterranean network to Assess and upgrade Monitoring and forecasting Activity in the region, a thematic network funded under the EC Programme Environment and Sustainable Development, 5th FP (EVR1-CT-2001-20010). Funds relevant to this work were partially provided by the SIMBIOS project (“Piano di Potenziamento della rete scientifica e tecnologica, Cluster Ambiente Marino”) of the Italian Ministry for Scientific Research (MIUR). The author wishes to extent his thanks to the colleagues of the Ad hoc Study Group on Benthic Indicators formed by the Ocean Science Section of the Intergovernmental Oceanographic Commission (IOC) of UNESCO for common effort in this initiative. I. Karakassis and J. L. Hyland, members of this group, are also gratefully acknowledged for providing fruitful discussion and for critical reading of an early version of this paper, respectively. Two anonymous reviewers also provided constructive criticisms and helpful comments that improved the manuscript.