Farm riparian land use and management: driving factors and tensions between technical and ecological functions.

Because of their specific role in the fate of natural resources of landscapes, riparian lands are considered as landscape management units. Yet, they are part of many farms: In what way does this influence their land use and sustainability? In this article, farm riparian land was defined as the set of riparian fields of a given farm. Our aim was to evaluate farm riparian lands as farm management units and the balance between technical and ecological functions associated with farm riparian land-use types. Technical functions designated the role of land use in elaborating farm production and maintaining farm territory. Ecological functions corresponded to farm riparian land-use intensity and ratio of permanent vegetation. The analysis was carried on 102 farms from 5 study sites representative of dairy agriculture and landscapes in a region straddling Brittany and Normandy (France). Farm riparian land-use types were identified using statistical clustering. Technical and ecological functions associated with land-use types were expressed in the light of agronomy and landscape ecology expertise. Descriptors of farm holdings and farm riparian land were tested as explanatory factors of farm riparian land-use types. The use of farm riparian lands was diverse but well defined; they proved to be farm management units. Compatibilities or antagonisms between technical and ecological functions were underscored according to farm riparian land-use type. We argued that decision support could gain in combining perspectives on riparian lands as landscape management units and farm management units.