Impacts of the French bio-fuel policy on the French arable crop sub-sector

The paper provides an analysis of the impacts of the biofuel policy on the French arable crop sub-sector. The model used is a biofuel supply model composed of an agricultural module and an industrial biofuel processing module. The agricultural supply model is an aggregation of 1094 farm models, based on data from the French Farm Accountancy Data Network (FADN). Different biofuel chains are included in the model: ethanol from wheat and sugar beet, biodiesel (Vegetable Oil Methyl Ester) from rapeseed and sunflower. Scenarios are built upon the recent policy of an increased demand of biofuels for the next years, under the assumption of fulfilling the targets with domestic production only. Results show that the incorporation target of 7% of biofuels in transport fuels would have small impacts on the wheat and sugar beet cultivated areas but would lead to a considerable increase in the rapeseed area. In the main producing regions, the rapeseed area would reach approximatively a third of the total farmed area. This would not be without consequences on the environment, due to the increase in pesticide use that this change in cropping patterns would most certainly induce. It would not be possible to reach a 10% incorporation target without imports. Furthermore, we analyse the impacts of reaching these production levels on the rapeseed opportunity costs, and show that reaching high level of incorporation (above 7%) will need a very high increase in rapeseed prices paid to farmers. We calculate the impacts of this opportunity cost increase on the competitiveness of biofuels with respect to fossil oil, for different levels of oil prices. We test the sensitivity of the results against the wheat price, and show that this latter will have a significant impact on the biodiesel competitiveness.biofuel, agriculture, France, Agricultural and Food Policy, Crop Production/Industries,

Spatially explicit farming system modelling for an efficient agri-environmental policy design

A mathematical programming model is developed and associated to a spatial pattern index (Ripley L-function) to analyse the optimal reserve design and implementation for the Little Bustard conservation in Plaine de Niort. The model structure corresponds to three spatial levels, fields, farm and landscape. Simple in terms of area representation it is detailed in term of farm behaviour and spatially explicit. The model is applied in a normative and in a positive way. The major findings of the normative approach relate to the trade-offs between the reserve pattern and its cost. It was found that the environmentally optimal reserve, which is randomly dispersed across the zone, is the most costly one. Within the positive approach, it is illustrated that the various reserve patterns generated within the normative approach can be obtained through relatively simple uniform contract structures. The most effective contract structure is a degressive set of two payments enabling all the farms to enrol at least a small share of their land.Biodiversity, spatial optimization, mathematical programming, agri-environmental policies, Tetrax tetrax, Agricultural and Food Policy, Environmental Economics and Policy, Research Methods/ Statistical Methods, Resource /Energy Economics and Policy,

Spatially explicit farming system modelling for an efficient agri-environmental policy design

A mathematical programming model is developed and associated to a spatial pattern index (Ripley L function) to analyse the optimal reserve design and implementation for the Little Bustard conservation in Plaine de Niort. The model structure corresponds to three spatial levels, fields, farm and landscape. Simple in terms of area representation, it is detailed in terms of farm behaviour and spatially explicit. The model is applied in a normative and in a positive way. The major findings of the normative approach relate to the trade-offs between the reserve pattern and its cost. It was found that the environmentally optimal reserve, which is randomly dispersed across the zone, is the most costly one. Within the positive approach, it is illustrated that the various reserve patterns generated within the normative approach can be obtained through relatively simple uniform contract structures. The most effective contract structure is a degressive set of two payments enabling the farms to enroll at least a small share of their land.Biodiversity, spatial optimization, mathematical programming, Environmental Economics and Policy, Farm Management,

Impacts du développement des biocarburants sur la production française de grandes cultures

The paper provides an analysis of the impacts of the bio fuel policy on the French arable crop subsector. The model used is a bio fuel supply model composed of an agricultural module and an industrial bio fuel processingule. Our results show that the incorporation target of 7% of bio fuels in transport fuels would lead to a considerable increase in the rapeseed area. In the main producing regions, the rapeseed area would reach approximately a third of the total farmed area. It would not be possible to reach a 10% incorporation target without imports. Furthermore, we analyse the impacts of reaching these production levels on the rapeseed opportunity costs, and show that reaching the incorporation targets will need an increase in rapeseed prices paid to farmers. We calculate the impacts of this opportunity cost increase on the competitiveness of bio fuels with respect to fossil oil, for different levels of oil prices.Agriculture , Bio-fuels , Energy policy , French arable crops

La révision à mi-parcours de la PAC (juin 2003) et les exploitations céréalières des régions intermédiaires

A l'aide d'un modèle régional d'offre optimisant le revenu agricole des exploitations sous un ensemble de contraintes et simulant parallèlement les évolutions des structures agricoles sur la période 2002-2012, les impacts du compromis de Luxembourg sur les revenus et sur les structures agricoles, sur les assolements et sur la déprise (non culture) ont été analysés, dans les régions céréalières intermédiaires. Les simulations montrent un léger risque de déprise, 8% des exploitations, si les prix des céréales diminuent nettement, 81€ à l'horizon 2012. Un recouplage de 25% des aides fait disparaître la déprise dans ce scénario de prix qui suppose une baisse du prix d'intervention. Suite au compromis de Luxembourg, le maintien du prix d'intervention devrait normalement empêcher une baisse aussi importante des prix et freiner donc naturellement la déprise. Alors que les ultimes propositions "Fischler" (scénario 1) auraient entraîné des baisses importantes de revenu agricole par hectare et par exploitation, le compromis de Luxembourg (scénario 2) devrait permettre un maintien du revenu par exploitation en euros constants (taux d'inflation 1,4%), sachant que 12% des exploitations disparaissent à l'horizon 2012, selon le modèle. Le découplage fait peu évoluer l'équilibre entre les céréales et les oléagineux, ce qui n'est pas surprenant puisque les aides couplées par culture sont identiques depuis l'application de l'Agenda 2000.

The future of global sugar markets: Policies, reforms, and impact

"Sugar is one of the most highly protected agricultural commodities worldwide. This protection depresses trade opportunities and the prices received by exporters without preferential market access. For this reason, dialogues about sugar policy are often polarized and short sound bites caustic. Yet today's sugar markets are being driven by a complex array of dynamic and emerging supply, demand, and policy forces that need to be understood. A number of these forces have the potential to reshape the global market scene. Recent sugar policy reforms in the European Union (EU) have received little attention in North America but may turn the EU into a net importer, with substantial compensation paid to its farmers and displaced processing facilities. High oil prices and the related ethanol boom place Brazil at the fulcrum of new market developments. In the United States, corn sweetener and sugar markets are being integrated with Mexican markets under the North American Free Trade Agreement (NAFTA), raising the question of whether the EU reforms provide a template for new policies. And among developing countries in Africa and elsewhere there are low-cost producers that would benefit from more open trade but others who would be disadvantaged by the loss of preferential markets. This discussion paper presents the proceedings of a one-day conference that served as a forum for the discussion of these and other critical issues affecting global sugar markets, policies, and reform options. The conference was attended by 60 representatives of governments, research institutions, producers and processors from the sugar sector, and other groups interested in sugar markets and policies. The four papers were presented by internationally recognized experts from the EU, Brazil, the United States, and South Africa. Discussion openers and general discussion at the conference added further policy insights, and the papers were edited and revised after the conference to reflect the dialogue that had occurred." from authors' abstractsugar, Ethanol, NAFTA, WTO, Trade policy,

Les producteurs de céréales en France (essai de caractérisation à partir des données de l'enquête 1983 sur la structure des exploitations agricoles)

Diffusion du document : INRA Station d'Economie et Sociologie rurales 65 rue de Saint-Brieuc 35042 Rennes Cedex (FRA)L'étude proposée ici des producteurs de céréales en France s'inscrit dans un ensemble dé travaux menés depuis longtemps sur les systèmes de grande culture à la Station d’Économie et de Sociologie Rurales de Grignon.Ce document apporte des précisions sur les différentes catégories de producteurs, en situe l'importance, en examine différentes caractéristiques tant physiques qu'économiques

Les enjeux du développement des biocarburants dans l’Union européenne

En mars 2007, le Conseil européen a annoncé qu’à l’horizon 2020, une proportion minimale de 10 % de biocarburants devrait être incorporée dans les carburants utilisés pour le transport routier. Les pouvoirs publics communautaires mettent en avant trois facteurs principaux pour justifier une telle ambition : la réduction des émissions de gaz à effet de serre (GES), la diversification des approvisionnements énergétiques et le soutien des revenus agricoles. Alors qu’on s’interroge sur les conditions dans lesquelles les 5,75 % d’incorporation fixés par le cadre législatif actuel pourraient être atteints en 2010, ce nouvel élan donné à la politique communautaire des biocarburants suscite plusieurs interrogations.

A graph-based approach identifies dynamic H-bond communication networks in spike protein S of SARS-CoV-2

We apply graph-based approaches to identify H-bond clusters in protein complexes. Three conformations of spike protein S have distinct H-bond clusters at key sites. Hydrogen-bond clusters could govern structural plasticity of spike protein S. Protein S binds to ACE2 receptor via H-bond clusters extending deep across interface.Corona virus spike protein S is a large homo-trimeric protein anchored in the membrane of the virion particle. Protein S binds to angiotensin-converting-enzyme 2, ACE2, of the host cell, followed by proteolysis of the spike protein, drastic protein conformational change with exposure of the fusion peptide of the virus, and entry of the virion into the host cell. The structural elements that govern conformational plasticity of the spike protein are largely unknown. Here, we present a methodology that relies upon graph and centrality analyses, augmented by bioinformatics, to identify and characterize large H-bond clusters in protein structures. We apply this methodology to protein S ectodomain and find that, in the closed conformation, the three protomers of protein S bring the same contribution to an extensive central network of H-bonds, and contribute symmetrically to a relatively large H-bond cluster at the receptor binding domain, and to a cluster near a protease cleavage site. Markedly different H-bonding at these three clusters in open and pre-fusion conformations suggest dynamic H-bond clusters could facilitate structural plasticity and selection of a protein S protomer for binding to the host receptor, and proteolytic cleavage. From analyses of spike protein sequences we identify patches of histidine and carboxylate groups that could be involved in transient proton binding.PSI COVID19 Emergency Science FundSpanish Ministry of Science, Innovation and Universities RTI2018-098983-B-I00Excellence Initiative of the German Federal and State Governments via the Freie Universitat BerlinGerman Research Foundation (DFG) SFB 107