OBJECTIVES

One of the levers for scaling up OA is to promote the circularity of nutrient flows, nitrogen and phosphorus in production systems at different levels of organization, ranging from infra-farm (plot, workshops) to supra-farm (groups of farms, region). However, little is known about how matter and nutrients are exchanged between OA farms and other sources of fertilization in the region, or about the associated energy invested related to these flows.

The intAB project seeks to identify the biophysical drivers of circularity between OA farms in a given region for the purpose of closing biogeochemical and energy flows. Its objectives are two-fold:

• to characterize the fertilization methods used by OA farmers in a given region;
• to develop and evaluate internal and external circularity indicators for OA farms.

RESOURCES

The project is based on the collection of data concerning exchanges of matter, nutrients and energy for ten farms involved in three different types of regional synergy:

1. Farms with compost/straw exchanges.
2. Arable farms without livestock or with monogastric production.
3. Specialized vegetable farms with high organic fertilization requirements.

The results will be contextualised by analyzing responses from a qualitative online survey on fertilization methods, targeting all OA farms within the study region (a part of Finistère).

The project's originality lies in:

• consideration of the energy cost of circularity;
• the system approach, to link the different levels of flow organization (farm and regional scales).

The intAB project calls on know-how in industrial ecology (circularity), process engineering (manure processing, nitrogen flows), agronomy and animal production (environmental assessment), and modeling.

Participants

INRAE units

• OPAALE, Rennes
• SAS, Rennes

Partners

• Réseau GAB-FRAB en Bretagne