Saint Laurent de la Prée Research Farm belongs to the French Institute for Agricultural Research (INRA). Since 2009, it has been implementing a mixed crop-livestock farming system based on agroecological principles in the marshes of the French Atlantic coast. The objectives are i) to design and experiment an agroecological system adapted to the local context, ii) to investigate its long-term environmental, economic and social performances and to iii) quantify the ecosystem services.
A ‘step-by-step’ approach is used, combining application of scientific knowledge, learning through try and failure, implementation of factorial trials, investigations on commercial farms for tracking innovations, and on-farm brainstorming sessions (with researchers, technicians and stakeholders).
This system experiment called ‘Transi’marsh’ covers an area of 160 ha. The fields are criss-crossed by a network of freshwater ditches. The farm covers 115 ha of permanent grasslands (wet grasslands) and 45 ha of non-irrigated arable land. The herd consists of 55 suckler cows and replacement heifers and calves. Stocking rate is moderate (0.7 LU/ha of fodder area).
The chosen system management applies a combination of agroecological practices: use of a local breed called Maraîchine native to the wetlands, implementation of landscape features to favour biological regulations, preservation of wild biodiversity, especially birds, by creating vegetation mosaics in grazed grassland, use of diversity of plant species and varieties in crops and temporary grasslands, use legumes in mixed crops that provide N in soil, and soil-covering crops to stop the use of chemical fertilisers and pesticides. In 2019, the farm has been converted to an organic farming system.
Transi’marsh offers multiple opportunities for researchers from a large range of scientific disciplines to participate to an agroecological project and analytical studies integrated in an holistic approach.
