Biodiversity puzzle

Environments to protect

In France, as in the rest of the world, the biodiversity is now in danger.
The phenomenon of fragmentation of natural environments, a consequence of human activities in the territories, has been identified for around ten years as one of the primary causes of species disappearance.
This awareness leads to reconsidering the management of natural environments from the perspective of ecological networks. No longer focusing on the protection of sites or species taken individually, it is now a question of developing an approach to management global of these environments.

And on the Grand Site?

Starting from the exceptional environments of the limestone grasslands , it is possible to characterize the ecological continuum of the Grand Site as follows:

• 5 reservoirs of biodiversity cover 120 ah and correspond to the site Natura 2000 “Calcicolous lawns of the Mâconnais”: Mont Sard, Roche de Vergisson, Rock of Solutre, Mont de Pouilly and Mont de Leynes. Within these entities, lawn habitats are in a generally satisfactory state of conservation. However, in certain areas, such as slopes with steep slopes surrounding rocks, these environments are intertwined with shrub thickets, favoring their fragmentation.
• 35 relay sites cover 44 ha. Scattered throughout the territory, these sites are characterized by very fragmentary lawn habitats, mosaic, with shrubby thickets.

Biodiversity reservoirs and relay sites thus only occupy 2% of the surface area of ​​the territory. This figure reflects the fragility of this ecological network whose main compartments are fragmented and isolated within a very impermeable landscape matrix (vine).
Only one connection area functional was identified in the Solutré valley, east of Grange du Bois. Dominated by bocage meadows, associated with a few fragments of lawns, this sector ensures a ecological continuity between Mont de Pouilly and Roche de Solutré.

Different potential connection areas, the functionality of which remains to be confirmed, have been highlighted. In the western part of the territory, these zones are made up of:

• the bocage meadows of the Arlois valley creating a probable connection between Mont de Leynes and Mont de Pouilly;
• bocage meadows and forest edges to the east and north of the Torvon massif forming a probable connection between the Roche de Solutré, the Roche de Vergisson and Mont Sard.

Risks to contain

In the eastern part of the territory, between Les Roches and the Petite Grosne valley, the connecting zones are organized in a more complex way around various relay sites, a few hedged meadows, and forest edges. This area, largely dominated by vineyards, presents numerous breaks in the grassland continuum. This phenomenon is particularly noticeable around Mont de Pouilly, with the absence of relay sites and the omnipresence of vineyards. In this area, the lack of natural or semi-natural vegetation cover , such as grass strips or relict grasslands bordering vineyards, renders the environments impermeable to the dispersal and movement of species associated with grassland habitats.

The functionality of the calcareous grassland network is therefore severely impaired in the Monts du Mâconnais region, particularly within the perimeter of the Solutré Pouilly Vergisson Grand Site de France. Beyond these biodiversity reservoirs , areas of high ecological importance require special attention to limit discontinuities and breaks in the ecosystem: the Solutré valley (Grange du Bois), the Arlois valley, the foothills of the Torvon Massif, and the relay sites around the Roche de Solutré and the Roche de Vergisson.