3 avril 2017
The impacts of climate change on French agricultural productivity
27 février 2017
Land use analysis and ecosystem services
Land use and land use change are among the major human pressures on the environment, especially on ecosystem services. This paper investigates the consequences of land use and land use change on biodiversity conservation and carbon sequestration. It gives insights about the trade-offs between private landowner economic goal and environmental objectives through a theoretical and an econometric models. We implement a theoretical approach where a representative landowner compares the land use rents to choose the optimal land use. Carbon sequestration and biodiversity are introduced through suitable indicators. We highlight trade-offs between economic (profit maximization) and environmental objectives (carbon sequestration and biodiversity conservation) by implementing different public policy scenarios (through taxes and subsidies). We test the previous insights with an econometric application. A land use share model is estimated for major land uses in France. Land use is explained by economic variables (land rents) and on biophysical variables (climate, soil characteristics). Several ecosystem services are taking into account and are function of land use share.
Pollution-adjusted productivity changes in French suckler cow farms: The use of a generalized multiplicatively complete Färe-Primont index
This article extends the multiplicatively complete Färe-Primont productivity index to a generalized version that considers pollution. The proposed total factor productivity (TFP) writes as the ratio of an aggregated good outputs to an aggregated bad outputs and non-polluting inputs in such a way that the materials balance principle is not distorted. A decomposition of the new pollution-adjusted total factor productivity (PTFP) is proposed using the by-production approach. In general, the by-production implies considering a global technology that lies at the intersection of two sub-technologies: one for the production of good outputs and the other for the generation of pollution. Using different assumptions, the PTFP is decomposed into pollution-adjusted technical and efficiency changes. The latter driver is further broken down into technical, scale, mix or residual efficiency changes components. A real advantage of the Färe-Primont index is the verification of the transitivity property which allows multi-temporal and multi-lateral comparisons. It is thereby useful for most panel databases at hand. The generalized Färe-Primont PTFP is illustrated in this article with a sample of French suckler cow farms surveyed over the period 1990 to 2013. The bad outputs considered are the greenhouses gases emissions namely methane (CH4), carbon dioxide (CO2) and nitrous oxide (N2O). The results reveal a decrease in pollution-adjusted TFP by 5.57% over the period, due to technological regress of 2.23%, and to technical efficiency decrease for almost 3.34%. This suggests that farmers did not have the right incentives to implement actions that would reduce such emissions during the period studied.
9 janvier 2017
Ressources renouvelables et aversion à l'inégalité : quelles conséquences pour le futur ?
Stellio Del Campo
This paper addresses intragenerational and intergenerational issues about a renewable natural resource exploitation. In particular, we analyze how different equity views, represented through a change in the intragenerational inequality aversion, influence the possible development paths for future generations. We suppose an agent has access to a renewable resource and works to exploit it, while another agent does not have access to it. A social planner implements a transfer mechanism from the former to the latter. We show that if the worker is originally better-off than the receiver, inequality aversion has a negative effect on the resource stock with a lump-sum transfer, but potentially a positive effect with a proportional tax. Reciprocally, the higher the stock the higher the possibilities for future consumptions. These links strongly suggest to deal jointly with the two equity dimensions in order to design consistent environmental policies.
12 décembre 2016
Les interrelations entre services écosystémiques et le rôle des politiques agroenvironnementales