Valuing the services of coastal ecosystems: a meta-analysis of contingent valuation studies

Abstract

Coastal ecosystems provide many and diverse functions, creating significant environmental values that should be taken into consideration during coastal management decisions. The most widely used method in coastal ecosystem valuation is contingent valuation, a method that can deal with the assessment of direct and indirect ecosystem uses and also of non-use motivations in natural resource economics. In this framework, the main aim of the present paper is to statistically examine the variation of coastal ecosystem values, as derived from 20 contingent valuation case studies. More precisely, this variation is explained by means of a meta-analysis application (meta-regression analysis), where the dependent variable is the willingness to pay for coastal ecosystems protection (or restoration), whereas the set of explanatory variables comprise three main categories of primary studies’ characteristics: (a) the environmental characteristics of the reference sites, (b) the site characteristics and (c) the methodological characteristics of the contingent valuation studies. The results of this paper show that all three categories comprise significant factors that explain the heterogeneity in coastal ecosystem values. Moreover, it has been found that specific site characteristics, such as the size of the reference coastal areas and the major environmental threats within these areas, are the most significant determinants of the variation in the willingness to pay. Finally, according to the outcome of a benefit transfer exercise performed on the results of the meta-regression analysis, the accrued set of estimators can be further applied in order to form a generalized benefit transfer function for the assessment of other coastal ecosystems.