Long-Term Trends in Intertidal and Subtidal Benthic Communities in Response to Water Quality Improvement Measures
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Long-term monitoring studies are needed to understand changes in ecosystem status when restoration measures are implemented. A long-term data series (1996–2007) of the Tagus estuary (Portugal) intertidal and subtidal benthic communities was collected in a degraded area where mitigation measures were implemented. Multivariate analysis was used to analyze spatial and temporal patterns in benthic community composition and trends in five benthic community metrics (i.e., taxonomic richness, density, biomass, Shannon–Wiener diversity and the AMBI index) were also examined. The results revealed a clear separation between intertidal and subtidal assemblages, although they had 50% of taxa in common, including the most abundant. Significant positive trends were found for all metrics showing that both intertidal and subtidal communities responded to the restoration measures implemented. Nevertheless, biotic indices need some adaptation before being universally applied to intertidal and subtidal habitats.
KeywordsBenthic quality assessment Long-term trends Spatial and temporal patterns Tagus estuary AMBI
This study was supported by the institutions Parque EXPO, S. A. and Lisbon Municipality. This study was also supported by a Post Doc fellowship (SFRH/BPD/29579/2006) granted by FCT. We would like to thank our colleagues V. Amaral, M.J. Correia, M. Cunha, F. Jorge, J.P. Medeiros, M. Pardal, C. Pereira, C. Pestana, A.L. Rego, S. Rodrigues, J. Salgado, and C. Teixeira for assistance in different tasks.
- Bachelet, G., and J.C. Dauvin. 1993. Distribution quantitative de la macrofaune benthique des sables intertidaux du bassin d’Arcachon. Oceanologica Acta 16: 83–97.Google Scholar
- Blanchet, H., N. Lavesque, T. Ruellet, J.C. Dauvin, P.G. Sauriau, N. Desroy, C. Desclaux, M. Leconte, G. Bachelet, and A.L. Janson. 2008. Use of biotic indices in semi-enclosed coastal ecosystems and transitional waters habitats—implications for the implementation of the European Water Framework Directive. Ecological Indicators 8: 360–372.CrossRefGoogle Scholar
- Boesch, D.F. 1977. A new look at the zonation of the benthos along the estuarine gradient. In Ecology of marine benthos, ed. B. Coull, 245–266. Columbia: University of South Carolina Press.Google Scholar
- Clarke, K.R., and N. Gorley. 2001. PRIMER v5: user manual/tutorial. Plymouth: PRIMER-E-Ltd., Plymouth Marine Laboratory.Google Scholar
- Clarke, K.R., and R.M. Warwick. 1994. Changes in marine communities: an approach to statistical analysis and interpretation. Plymouth: Plymouth Marine Laboratory.Google Scholar
- Ferreira, J.G., T. Simas, A. Nobre, M.C. Silva, K. Shifferegger, and J. Lencart-Silva. 2003. Identification of sensitive areas and vulnerable zones in transitional and coastal Portuguese systems. Application of the United States National Estuarine Eutrophication Assessment to the Minho, Lima, Douro, Ria de Aveiro, Mondego, Tagus, Sado, Mira, Ria Formosa and Guadiana systems. INAG and IMAR. http://www.eutro.org/documents/NEEA%20Portugal.pdf.
- Gilbert, R.O. 1987. Statistical methods for environmental pollution monitoring. New York: Wiley.Google Scholar
- Kendall, M.G. 1975. Rank correlation methods, 4th ed. London: Charles Griffin.Google Scholar
- Legendre, L., and P. Legendre. 1976. Écologie numérique. I: Le traitement multiple des données écologiques. Paris: Masson.Google Scholar
- Mann, H.B. 1945. Non-parametric tests against trends. Econometrica 18: 163–171.Google Scholar
- Pereira, C.D., M.J. Gaudêncio, M.T. Guerra, and M.T. Lopes. 1997. Intertidal macrozoobenthos of the Tagus estuary (Portugal): the Expo’98 area. Publicaciones Especiales del Instituto Español de Oceanografía 23: 107–120.Google Scholar
- Warwick, R.M., C.M. Ashman, A.R. Brown, K.R. Clarke, B. Dowell, B. Hart, R.E. Lewis, N. Shillabeer, P.J. Somerfield, and J.F. Tapp. 2002. Inter-annual changes in the biodiversity and community structure of the macrobenthos in Tees Bay and the Tees estuary, UK, associated with local and regional environmental events. Marine Ecology Progress Series 234: 1–13.CrossRefGoogle Scholar