Socio-economic diagnosis of a small region using an economic modeling tool (Olympe): An approach from household to landscape scales to assist decision making processes for development projects supporting conservation agriculture in Madagascar

Two agricultural development projects based on conservation agriculture and agriculture/livestock integration are currently being implemented in Madagascar that takes into account both a "watershed approach" and a "farming system approach" for dissemination of adapted technologies: BV-lac in the area of Lake Alaotra and BVPI-SEHP in Vakinankaratra (Central highlands) and South-East. A farming systems reference monitoring network (FSRMN) has been set up since 2007 with two objectives: i) to help the project in decision making processes for choosing appropriate technologies that will be developed according to a farmer's typology using prospective analysis, ii) to monitor the project's economical impact in the short and medium term. A farming system modelling approach using a software developed by INRA-CIRAD-IAMM ("Olympe", JM Attonaty, INRA), has been developed with project operators in order to cope with the local context and its diversity to promote the best adapted technologies for farmers' conditions including Direct Seeding mulch-based cropping systems conservation tillage (DMC or Conservation Agriculture) and livestock integration. Meantime a new land titling method through "land certification" has been developed since 2003 to secure land tenure. The approach is based on partnership (smallholder, farmers' organizations, project operators and local administration), farming system analysis, and modelling for a Decision Support Systems (DSS) project orientation. This paper presents the methodology, the tools, and some results from the BV-lac project in the lake Alaotra region. FSRMN and farming system modelling (FSM) linked with innovation process assessment tools lead to identification of local innovation processes, adoption and/or adaptation of DMC systems by farmers in order to understand farmers' strategies and to adapt technologies to the farmers' situations and constraints. Adoption of conservation agriculture (CA) represents both a real change of paradigm for local farmers and a real challenge for agriculture and natural resources sustainability. The model provides economic results displaying the real income improvement and impact on farming practices, labour and organizational changes (credit ¿). FSRMN and FSM have been so far well adopted as tools at project levels to cope with the best combination between farmers' needs and the projects' proposals for DMC techniques. At the regional level, CA adoption and livestock integration at farm level, linked with reforestation and regreening on slopes at watershed level provide positive externalities in terms of erosion protection, soil fertility restoration, production consistency and long term based sustainable patterns of production. (Résumé d'auteur