MEPS 494:1-27 (2013)  -  DOI:

Framework for understanding marine ecosystem health

P. Tett1,*, R. J. Gowen2, S. J. Painting3, M. Elliott4, R. Forster3, D. K. Mills3, E. Bresnan5, E. Capuzzo3, T. F. Fernandes6, J. Foden3, R. J. Geider7, L. C. Gilpin8, M. Huxham8, A. L. McQuatters-Gollop9, S. J. Malcolm3, S. Saux-Picart10, T. Platt10, M.-F. Racault10, S. Sathyendranath10, J. van der Molen3, M. Wilkinson6

1Scottish Association for Marine Science, Scottish Marine Institute, Oban, Argyll PA37 1QA, UK
2Agri-Food and Biosciences Institute, Newforge Lane, Belfast BT9 5PX, UK
3Centre for Environment, Fisheries and Aquaculture Science, Pakefield Road, Lowestoft, Suffolk NR33 0HT, UK
4Institute of Estuarine and Coastal Studies, University of Hull, Hull HU6 7RX, UK
5Marine Scotland Science, Marine Laboratory, PO Box 101, 375 Victoria Road, Aberdeen AB11 9DB, UK
6School of Life Sciences, Heriot-Watt University, Riccarton, Edinburgh EH14 4AS, UK
7School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, UK
8School of Life, Sport & Social Science, Edinburgh Napier University, Edinburgh EH11 4BN, UK
9Sir Alister Hardy Foundation for Ocean Sciences, The Laboratory, Citadel Hill, Plymouth PL1 2PB, UK
10Plymouth Marine Laboratory, Prospect Place, The Hoe, Plymouth PL1 3DH, UK

ABSTRACT: Although the terms ‘health’ and ‘healthy’ are often applied to marine ecosystems and communicate information about holistic condition (e.g. as required by the Ecosystem Approach), their meaning is unclear. Ecosystems have been understood in various ways, from non-interacting populations of species to complex integrated systems. Health has been seen as a metaphor, an indicator that aggregates over system components, or a non-localized emergent system property. After a review, we define good ecosystem health as: ‘the condition of a system that is self-maintaining, vigorous, resilient to externally imposed pressures, and able to sustain services to humans. It contains healthy organisms and populations, and adequate functional diversity and functional response diversity. All expected trophic levels are present and well interconnected, and there is good spatial connectivity amongst subsystems.’ We equate this condition with good ecological or environmental status, e.g. as referred to by recent EU Directives. Resilience is central to health, but difficult to measure directly. Ecosystems under anthropogenic pressure are at risk of losing resilience, and thus of suffering regime shifts and loss of services. For monitoring whole ecosystems, we propose an approach based on ‘trajectories in ecosystem state space’, illustrated with time-series from the northwestern North Sea. Change is visualized as Euclidian distance from an arbitrary reference state. Variability about a trend in distance is used as a proxy for inverse resilience. We identify the need for institutional support for long time-series to underpin this approach, and for research to establish state space co-ordinates for systems in good health.

KEY WORDS: Ecosystem approach · Functional and response biodiversity · Resilience · State space · Regime shift · EU Marine strategy Framework Directive

Full text in pdf format 
Supplementary material
Information about this Feature Article
Cite this article as: Tett P, Gowen RJ, Painting SJ, Elliott M and others (2013) Framework for understanding marine ecosystem health. Mar Ecol Prog Ser 494:1-27.

Export citation
Mail this link - Contents Mailing Lists - RSS
- -