Agricultural intensification has degraded ecosystems, and it is now necessary to take greater account of the role of biodiversity in agrosystems and its importance for ecosystem services provision. For the past two decades, cultivators in vineyards have been improving their sustainable management practices, developing a vegetation cover inside inter-rows to limit soil erosion, and an extensive management of plot edges and networks of ditches. These practices support the development of a spontaneous vegetation cover, a source of numerous ecosystem services including for example runoff regulation, water erosion mitigation and organic pollutants retention. 
This is a major challenge, particularly in Mediterranean vineyards, where climate change is likely to increase the frequency of intense rainfall.

Objectives

In order to limit the negative effects of agricultural intensification, it is necessary to rethink the interactions between ditches, inter-rows of perennial crops, headlands and agricultural plots. These elements host a spontaneous vegetation that provides numerous ecosystem services in terms of regulation and supply, and facilitates water circulation in the landscape. WATERSEED will analyse how water structures the distribution patterns of plant communities, the dispersal of seeds by water and the spatial structure of species according to soil moisture gradients.

Resources

This project will include:

1. Characterisation of the plot and interstitial environment, using 3D reconstruction methods (photogrammetry) and a network of humidity sensors.
2. Measuring the composition of the seed bank in the environments mentioned earlier, thanks to spontaneous germination experiments.
3. Measuring seed flows between cultivated and interstitial environments using innovative monitoring methods.

(a) Location of the OMERE observatory, with the layout of the ditch network in blue, the potential plots in purple, and the moisture sensors to be installed in yellow, (b) the plot for the study of seed flows between the plot and the interstitial environment, and in red the position of soil seed bank samples, (c) an enlargement of the downstream zone of the plot showing the alternating grassing of the inter-rows and the location of the devices for capturing run-off water (Gerlach devices, illustrated in (d)).

The ecosystem services associated with plant biodiversity will be estimated using field samples: biomass, fraction of plant cover, chemical composition of the biomass and associated microbial communities, in relation to edaphic conditions. The species identified will be linked to ecosystem functions via databases (e.g. the TRY
database) to determine qualitative traits: nectariferous potential, competition with crops.

INRAE units involved

• Département AQUA
  • G-EAU Joint Research Unit - Water Management, Actors, Territories
• Département AGROECOSYSTEM
  • LISAH Joint Research Unit - Soil-Agrosystem-Hydrosystem interaction lab
  • ABSYS Joint Research Unit – Biodiversified Agrosystems

External partnerships

• Laboratoire CITERES Joint Research Unit - Université de Tours - Cities, Territories, Environment and Societies