Diversité agricole et patrimoine dans le moyen Rio Negro (Amazonie brésilienne)

International audienceLocal norms and practices about perception and management of agrobiodiversity are seen as a biologic cum cultural heritage. How can they be articulated with Brazilian recent juridical norms on biodiversity and traditional knowledge? In this paper, we develop a methodological approach for interdisciplinary study of agrobiodiversity in multiple scales (domestic unit, village, region). We offer some results of its application on the mid-Rio Negro region, in a pluriethnic context. The agricultural system is based on slash and burn pratices in a low density area. Three study areas were chosen : two of them are forest villages and one is an urban area (7,000 inhabitants).). Agricultural diversity was studied with 4, 5 and 9 families respectively The results show a broad agrobiodiversity (243 cultivated plants and 73 varieties of manioc for 18 families). Under current conditions, this diversity is maintained in the urban area as well. We stress the different plant collections managed by each woman agriculturalist. Such high diversity is linked to an extremely active and wide circulation of plants between spaces and people in different scales. Resources were socially and geographically mapped, and they showed a flux that extends 500 km up as well as 500 km down river. However, most of these exhanges take place in the village and its vicinity and are associated with kinship. In town, the flux is determined by neighborhood and economic factors rather than by family links. In both cases, plant circulation takes place outside of agricultural development institutions, markets and economic relations. They belong to a larger system of exchange in which phytogenetic resources are not individually owned. Furthermore, agricultural diversity is related to a very rich handicraft culture and to a complex food system. Finally, we argue that legal tools currently being built in Brazil around phytogenetic resources are not conducive to the preservation and valorisation of an agricultural system which produces diversity such as the one we describe the mid-Rio Negro region. As things stand now, registering that system as cultural heritage could provide a better acknowledgement of its worth, give it visibility and ensure its conservation.La question posée est d'identifier comment les normes et pratiques locales de perception et gestion de l'agrobiodiversité s'articulent aux instruments juridiques de conservation et valorisation de la biodiversité et savoirs associés récemment mis en place au Brésil. L'article comprend deux volets, une proposition méthodologique pour une approche interdisciplinaire de l'agrobiodiversité et l'application de cette approche à la région du moyen Rio Negro. Les résultats portent sur l'amplitude de la diversité agricole, le rôle fondamental de la circulation des variétés et espèces cultivées dans le maintien d'une diversité élevée, sa dimension culturelle et régionale. En conclusion, nous mettons en regard la construction patrimoniale de l'agrobiodiversité avec les différents instruments de conservation discutés aujourd'hui au Brésil