-The role of landscape valuation and extended cost-benefit analysis in landscape conservation decision-making is first addressed. It is stressed that substantial research on how to value alternative conservation schemes is required, in order to cope with emerging policy needs. An analytical frame for the valuation of alternative landscape conservation schemes is then discussed. This frame enables the analyst to sequentially disaggregate values for whole landscape changes over attributes. This is an essential operation if the optimal bundle of landscape attributes is to be selected by cost-benefit analysis. The concept of substitution between landscape attributes plays an essential role within the whole analytical frame. The circumstances that lead to anticipate substitution between landscape attributes are explored. A brief review of the alternative empirical strategies for landscape valuation is then carried out, to check whether they permit sequential desegregation of landscape value over attributes. Next, an empirical application to the valuation of landscape attribute changes in the Pennine Dales Environmentally Sensitive Area is presented. The empirical results confirm the idea of the prevalence of substitution in valuation in most practical contexts. To illustrate the potential of the proposed approach, a sequential cost-benefit analysis of attribute changes along consistent paths of aggregation is then carried out -which eventually leads to the selection of optimal bundles of landscape attributes. Some problems and limitations of the approach are also discussed. Among them, the question of non-uniqueness, or path dependency of the optimum is given particular consideration.
Resumo -VALORAÇÃO DE MUDANÇAS PAISAGÍSTICAS MULTI-ATRIBUTOS: UMA ANÁLISECUSTO-BENEFÍCIO PARA A SELECÇÃO DE PAISAGENS ÓPTIMAS. Abordam-se primeiramente os papéis da valoração económica da paisagem e da análise custo-benefício no quadro da concepção e avaliação de programas de conservação da paisagem, colo-Professor Auxiliar, Departamento de Economia Agrária e Sociologia Rural, Instituto Superior de Agronomia.Uma versão anterior deste artigo foi apresentada na 7.ª Conferência Anual da EAERE (European Association of Environmental and Resource Economists), realizada em Lisboa (1996). O autor agradece ao Professor Ken Willis (Universidade de Newcastle) e ao Professor Fernando Oliveira Baptista (Universidade Técnica de Lisboa) o seu apoio e comentários a uma versão preliminar deste artigo. Todas as opiniões e erros são, naturalmente, da responssabilidade exclusiva do autor. A investigação que esteve na origem do artigo foi financiada pela JNICT (bolsa PRAXIS XXI/BD/4519/94) e o inquérito referido no texto foi financiado pelo Environmental