Les territoires d'exploitations agricoles qui pratiquent des systèmes de production différents présentent-ils une biodiversité différente? L'exemple des oiseaux nicheurs

Agri-environmental policies are most often applied at the individual farm level. An improved effectiveness of these policies could result from an it is then necessary to study the ecological patterns by consi dering the level of agricultural organisation. However, many studies are currently lead at the field scale or the landscape scale without considering the whole farm territory. Our study focus on the relationships between bird diversity in farmland and spatial patterns of farming system types regarded as a level of agricultural organisation.We test 2 hypotheses: -The farming systems can discriminate bird diversity. - Landscape areas with extensive farming systems have an higher bird diversity than the ones with intensive farming systems because they include more semi-natural elements