The BACCHUS biodiversity and viticulture exeprimental site focuses on the dynamics of biodiversity in wine-growing landscapes and more generally proposes to evaluate the agronomic and environmental performance of wine-growing systems under real production conditions.
An experimental device designed on the scale of viticultural landscapes
Beyond wine-making practices at the plot level, we are interested in the effects of the structure of wine-growing landscapes on the dynamics of biodiversity and the ecosystem services it supports. Indeed, the structure of the wine landscape strongly influences population dynamics or the behaviour of a wide range of species. For example, so-called "semi-natural" habitats (HSNs) such as woods, grasslands and hedges are known to support a wide variety of vertebrates and invertebrates that also provide important services, such as natural pest control. So how can wine-growing landscapes be organised to reconcile agricultural production with the preservation of biodiversity?
To answer this question in a robust way, an experimental system designed on a landscape scale is implemented on the BACCHUS exeprimental site by sampling annually vineyard plots located along two uncorrelated landscape gradients: a gradient of proportion of semi-natural habitats and a gradient of proportion of organic agriculture (within a radius of 1 km around each plot).
A gradient in the proportion of semi-natural habitats
Semi-natural habitats play an important role in maintaining arthropod biodiversity in landscapes, often hosting at least one stage of their life cycle. These environments, which are less disturbed than agricultural areas, offer resources necessary for the survival of a large number of species, provided that they are present in sufficiently significant proportions for the species in question.
The gradient of landscape heterogeneity implemented in the experimental system thus makes it possible to observe the performance of viticultural systems in landscape contexts more or less dense in HSN: can a vineyard plot surrounded by meadows and forests better regulate the vine's leafroller pressures than a plot surrounded by vines?
A gradient in the proportion of organic viticulture
Agricultural practices are a particularly structuring factor for auxiliary communities and natural regulation, particularly fertilization, pest control, tillage practices, cultivated varieties, etc. It has thus been shown that organic farming systems host on average 1.3 times more species at the parcel scale.
This landscape gradient makes it possible to answer the question of the consequences of the deployment of organic farming on a territory scale on the performance of wine-growing systems. Do they host more biodiversity? Are they more affected by vine diseases due to a reduced use of pesticides?