all the Ille et Vilaine department, south of the Mont-Saint-Michel Bay (48° 36? N, 1° 32? W) in Brittany (France).
It is composed of three principal areas:
- the area near Pleine-Fougères (since 1993) The bocage area is characterized by a landscape gradient ranging from a dense hedgerow network with small fields by hedges to a less dense hedgerow network.The hedgerows bordering the fields are most often composed of pruned trees, oaks with pruned chestnuts, but also trees.Due to the introduction of environmental protection conditions in the Common Agricultural Policy, most rivers are bordered by grass strips since 2005.
- the marsh area located in the alluvial plain of the Bas-Couesnon (since 2006) The marsh area includes marshes located in Brittany also in Normandy.The low valley of the Couesnon, due to its proximity to the Mont St Michel bay and the presence of numerous wetlands is of great heritage interest and is subject to the application of several perimeters of protection (Natura 2000) or scientific inventories (ZNIEFF, ZICO, ...).The selected area includes a set of five marshes with a wide variety of landscape structures, management histories and agricultural practices of water management.
- the urban are comprising the territory of Rennes Métropole (since 2011) The urban area corresponds to the territory of Rennes city.Rennes city has 20,960 inhabitants in 2012, which makes it the first city in the Brittany region and the eleventh most populous city in France in terms inhabitants. More specifically, an urban observatory has been set up, "the St Martin grasslands" site.This observatory corresponds to the rehabilitation of an old industrial site into an urban park.
In addition to these three main areas, there are two observatory sites:
- the bog of Landemarais. Integrated the ZA in 2016, it belongs to the SNO "Peat Moss" whose purpose is to evaluate the impact of global changes on the carbon sink function of temperate peatlands. It is also a sensitive natural area (SNA) of the Ille-et-Vilaine county (35).
- in the south of the Ille-et-Vilaine department. Constituted in 2012 20 1km² landscapes, selected to represent i) a gradient of organic farming system in the landscape, as opposed to system, ii) a gradient of wooded (woodland, hedgerows) elements independent of the previous one. This observatory site is very complementary to the "agricultural" area (represented by the bocage and marshland entities) because it proposes, for the same landscape context, a fine gradient of heterogeneity in management practices (biological vs. conventional).
The Mont Saint Michel polders constitute, in the northern part of the ZA, occasional study sites.