Integrated ecological-economic modelling and assessment aproach for coastal ecosystem management

Thesis submitted to the Faculty of Sciences and Technology, New University of Lisbon, for the degree of Doctor of Philosophy in Environmental Sciences

Over the past few decades, policy-makers have defined new instruments to address coastal ecosystem degradation. Emerging coastal management frameworks highlight the use of the best available knowledge about the ecosystem to manage coastal resources and maintain ecosystem’s services. Progress is required, however, in translating data into useful knowledge for environmental problem solving. This thesis aims to contribute to research assessing changes in coastal ecosystems and benefits generated due to management actions (or to the lack thereof). The overall objectives are to assess the ecological and economic impacts of existing management programmes, as well as future response scenarios and to translate the outcomes into useful information for managers. To address these objectives, three different approaches were developed: A multilayered ecosystem model A multilayered ecosystem model was developed to simulate management scenarios that account for the cumulative impacts of multiple uses of coastal zones. This modelling field is still at an early stage of development and is crucial, for instance, to simulate the impacts of aquaculture activities on the ecosystem, accounting for multiple farms and their interactions with other coastal activities. The multilayered ecosystem model is applied in this thesis to test scenarios designed to improve water quality and manage aquaculture. An ecological-economic assessment methodology (ΔDPSIR approach) The Differential Drivers-Pressure-State-Impact-Response (ΔDPSIR) approach further develops the integrated approach by providing an explicit link between ecological and economic information related to the use and management of coastal ecosystems. Furthermore, the ΔDPSIR approach provides a framework to synthesise scientific data into useful information for the evaluation of previously adopted policies and future response scenarios. The ΔDPSIR application is tested using different datasets and scales of analysis, including: (i)assessment of the ecological-economic impacts of the scenarios at the waterbody/watershed level, using the multilayered ecosystem model outputs, and (ii) evaluation of the ecologicaleconomic effects of aquaculture options at the individual aquaculture level, using data from an abalone farm. These are two important scale of analysis for the development of an ecosystem approach to aquaculture.A dynamic ecological-economic model (MARKET model) One of the missing links in ecosystem modelling is with economics. The MARKET model was developed to simulate the feedbacks between the ecological-economic components of aquaculture production. This model was applied to simulate shellfish production in a given ecosystem under different assumptions for price and income growth rates and the maximum available area for cultivation. Further application of the MARKET model at a wider scale might be useful for understanding the ecological and economic limitations on global aquaculture production. This integrated ecological-economic modelling and assessment approach can be further applied to address new coastal management issues, such as coastal vulnerability to natural catastrophes. It can also support implementation of current legislation and policies, such as the EU Integrated Coastal Zone Management recommendation or the development of River Basin Management Plans following the EU Water Framework Directive requirements. On the other hand, the approach can address recurring coastal management needs, such as the assessment of the outcomes of past or on-going coastal management plans worldwide, in order to detect symptoms of the overuse and misuse of coastal ecosystems.

Portuguese Foundation for Science and Technology(FCT) as a Ph.D. scholarship (SFRH/BD/25131/2005.European Union, Sixth Framework Programme FP6-2002-INCO-DEV-1 SPEAR (INCO-CT-2004-510706) project