THE LIMITS OF ECONOMIC VALUATION OF BIODIVERSITY

Facing the accelerated decline of biological diversity and the limits of the available resources to check it, it is necessary to determine which means should be engaged in its protection. To do so, an effective method would be to evaluate the benefits provided by biodiversity to estimate rationally the justifiable costs of its protection. The economic evaluation, methodologically quantitative, would be then a precious tool. In this text, we present various methods of economic evaluation of biodiversity as well as some of their methodological limits. Next, we show that in spite of its practical advantages, economic evaluation fails to represent all the values at stake in the protection of biodiversity. We then describe three types of values that are incommensurable with economical profits: the value of legacy, which refers to the obligations of transmission of the natural heritage originally handed down to us; the value of existence, which refers to the moral consideration of interests other than those of the human beings; the value of transformation, which refers to the capacity to examine and to criticize our preferences in order to include them in a rational and coherent vision of the world. To conclude, we plead in favour of the elaboration of participative and pluralistic methods of dialogue and evaluation allowing us to register the diversity and heterogeneity of the values of biodiversity.