A double benefit of biodiversity in agriculture

This paper examines the role played by biodiversity goals in the design of agricultural policies. A bio-economic model is developed with a dynamic and multi-scale perspective. It couples biodiversity dynamics, farming land-uses selected at the micro level and public policies at the macro level based on financial incentives for land-uses. The public decision maker provides optimal incentives with respect to both biodiversity and budgetary constraints. These optimal policies are then analyzed through their private, public and total costs. The model is calibrated and applied to metropolitan France at the Small Agricultural Region (SAR) scale using common birds as biodiversity metrics. Results put forward a decreasing and concave efficiency curve for different biodiversity indicators and economic scores stressing the underlying bio-economic trade-off. The analysis of total and public costs also suggests that accounting for biodiversity can generate a second benefit in terms of public budget. It is argued how a regional redistribution of this public earning to the farmers could promote the acceptability of biodiversity goals in agricultural policies.