Résumé
The aims of this paper are to delineate some important topics in landscape economics, and also to put landscape policy in the perspective of the sustainable development. The research issue is about the relationships between the development paths and landscape changes, paved with examples of consensus, controversies, and conflicts. Landscape is a polysemic term, many approaches and definitions exist for it, and as a consequence, economists should adopt or elaborate their own landscape definition or concept (the most suitable to their general methodology, and related to their most familiar concepts). Landscape appears to be a local public good. That definition correspond to the property rights market failure arising from the co-visibility. Co-visibility makes it difficult in general to identify precisely the link between each owner action and the agregate landscape outcome. As a consequence, landscape ownership appears to be scattered into a multiplicity of actors of various nature (individual, communal, statal…). How to exploit that analogy with non point source pollution is a challenge for landscape economics research. Each actor has his own objective and management criteria, either for agricultural, forestry, industrial or residential activities. Moreover, there are multiple public policies aimed at sustaining each activity. Inevitably, public policies failures arise, and so the need for coordination actions aimed at landscape maintenance and preservation. Because the local public good nature of the landscape, it’s worth to look at the models of public good joint production. How to agregate actions from different land owners into a resulting landscape, or how to coordinate actions scattered among multiple landowners in order to get a specific desired outcome is a real challenge ? In some case, the responsability of changes is concentrated in the hand of few decision makers, in some others, the responsability is more diffuse, and the non point production function of the landscape could be approximated by an additive function. The issue of the agregation of actions is closely related to the one of preferences heterogeneity and agregation. Because a specific landscape project could be appreciated as beneficial or detrimental by different people, it’s necessary to separate the stage of evaluation, the stage of decision making and the stage of implementation. Issues of coordination of actions arising at the implementation stage should take for granted the landscape objectives and the social value of the project. Eventually, the design of Institutional arrangements to manage landscape should take onto account his nature of common pool resource. The paper is organized so as to take stock from the contributions of the research community in Landscape economics, and also to signal some missing links and promising paths. Naturally, our paper does not exhaust all the topics, we will concentrate on three topics : preferences definition and evaluation, joint production, and governance.