Comparative analysis of the efficacy of multimetric indices based on fish communities in order to assess the ecological quality of coastal waters

• Author(s): Pires, Sofia Nunes Henriques Margarido
• Date: 2008
• Persistent ID: http://hdl.handle.net/10451/1404
• Origin: Repositório da Universidade de Lisboa
• Subject(s): Ictiologia; Gestão ambiental; Gestão de recursos marinhos; Teses de mestrado
• Document Type: Master thesis
• Language: English
• Advisor(s): Cabral, Henrique N.; Costa, Maria José Rosado
• Contributor(s): Repositório da Universidade de Lisboa

Description

Tese de mestrado em Ecologia e Gestão Ambiental, apresentada à Universidade de Lisboa, através da Faculdade de Ciências, 2007

Resumo alargado em português disponível no documento

Due to the increase of the anthropogenic pressures on the marine environment, the assessment of ecological status has become an essential tool to recover and protect it (e.g. European Marine Strategy Directive) emphasising the need for an efficient ecological index applied to this environment. Since none of the fish-based multimetric indices was developed to the marine environment, the present study had two main goals: to evaluate the efficacy of the existing indices and the development of an efficient multimetric index to promote the assessment of the ecological quality of the marine fish communities. Five estuarine indices were adapted to marine waters through the simple replacement of the functional estuarine groups for the marine ones and tested in fifteen zones of the Portuguese coast divided according to their substrate. Analysis of individual metrics suggests lack of representativeness and consideration for the particularities of each substrate's typical fish communities. These results strengthened the need of a new multimetric index development by type of substrate and depth. Recurring to a Drivers-Pressures-Impacts-Responses approach and previous studies, a set of metrics was selected and their redundancy was tested through multiple correlation matrices. Based on these results and ecological meaning of each metric, the Marine Fish Community Index (MFCI) was developed and divided in four typologies. Although, in the future, a good monitoring plan is need in order to solve some metric problems and to validate the reference values, the results of the MFCI application and it robustness test showed that this approach by typology is efficient to assess the ecological status. Therefore, a new index to assess the ecological status was successfully developed and can be applied on the evaluation of the quality of the marine environment