Essai de cartographie des massifs potentiellement sensibles aux incendies estivaux à l'horizon 2040 -

International audienceL'étude présentée a été réalisée conjointement par l'ONF, l'IFN et Météo-France, sur commande de la mission interministérielle sur l'extension des zones sensibles aux feux de forêts, qui a rendu son rapport en juillet 2007. Il s'est agit de modéliser la sensibilité de la végétation aux feux estivaux, sur l'ensemble du territoire français, en se basant sur un certain nombre d'hypothèses, par analogie avec ce que les experts connaissent des feux de l'arrière-pays méditerranéen. Les différents paramètres (végétation, réserve en eau des sols, météo) pris en compte, les hypothèses sur leur évolution et la façon de les combiner sont exposés, puis les cartes résultantes sont présentées pour la période de référence (1989-2008), ainsi que pour les modélisations aux horizons 2040 et 2060. Pour terminer, les conclusions de la mission sont évoquées dans leurs grandes lignes en renvoyant au rapport pour plus de détails

Possibles consequences of climate changes on forage production in France. II. Some examples of livestock systems.

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Use of agricultural statistics to verify the interannual variability in land surface models: a case study over France with ISBA-A-gs

In order to verify the interannual variability of the above-ground biomass of herbaceous vegetation simulated by the ISBA-A-gs land surface model, within the SUR-FEX modelling platform, French agricultural statistics for C3 crops and grasslands were compared with the simulations for the 1994-2008 period. While excellent correlations are obtained for grasslands, representing the interannual variability of crops is more difficult. It is shown that, the Maximum Available soil Water Capacity (MaxAWC) has a large influence on the correlation between the model and the agricultural statistics. In particular, high values of MaxAWC tend to reduce the impact of the climate interannual variability on the simulated biomass. Also, high values of MaxAWC allow the simulation of a negative trend in biomass production, in relation to a marked warming trend, of about 0.12Kyr(-1) on average, affecting the daily maximum air temperature during the growing period (April-June). This trend is particularly acute in Northern France. The estimates of MaxAWC for C3 crops and grasslands, currently used in SURFEX, are about 129 mm and do not vary much. Therefore, more accurate grid-cell values of this parameter are needed

Conséquences possibles des changements climatiques sur la production fourragère en France: I. Estimation par modélisation et analyse critique

National audienceClimate changes carries a risk but also an advantage for forage production, it influences both forage production levels and forage calendar. The results of a single climate model (Arpege) applied to different scenarios of global economic growth, have helped develop the STIC crop model (ACTA-CC project). This model, combined with a thorough knowledge of present and possible practices, provides useful information. For instance, it can help determine possible changes affecting forage grass, maize and alfalfa crops in the main French forage production regions over determined periods of time in the future (21st century). Methods and results are discussed. A second study will apply these scenarios to different types of animal production.Les changements climatiques, maintenant certains, agissent non seulement sur les niveaux des productions de ressources fourragères, mais aussi sur leurs calendriers. Les résultats de modèles de climat de Météo-France (Arpege), sous divers scénarios d’évolution économique mondiale, ont permis d’alimenter le modèle de culture STICS, dans le cadre d’une étude nommée ACTA-CC. L’utilisation de STICS, combinée à une bonne connaissance des pratiques présentes et possibles, montre les évolutions possibles des productions de graminées fourragères, maïs et luzerne à différentes échéances temporelles du XXI e siècle dans les principales régions fourragères françaises. Méthodes et résultats sont discutés. Un second article appliquera ces évolutions à différents ateliers de production animale

Conséquences possibles des changements climatiques sur la production fourragère en France. II. Exemples de quelques systèmes d’élevage

National audienceClimate change, now an acknowledged fact, affects both forage production levels and forage calendar. Simulated production of grass, alfalfa and maize, obtained using a cultivation model, were merged with the modelled representations of the requirements for 13 types of livestock farming systems. Medium and long-term problems affecting livestock feed resources are presented (scenario A2). Reliance on feed stocks and other types of stocks will be increased, and maize will play a more important role. Decreased summer rainfall will make it very difficult to sustain grassland farming systems. On-site expert knowledge of current and possible practices will help provide technical solutions, and determine the issues for which research and experimentation should be carried further.Les simulations de productions d’herbe, de luzerne et de maïs, obtenues en sortie d’un modèle de culture (cf. le premier article) sont combinées aux représentations modélisées des besoins de 13 types de systèmes d’élevage. Les questions d’alimentation des troupeaux qui se poseront à moyen et long terme (scénario A2) sont présentées : le besoin de stocks et sans doute la place du maïs devraient s’accroître ; les systèmes herbagers seront sans doute très difficiles à maintenir en raison de la réduction des précipitations estivales. La connaissance par des experts de terrain des pratiques présentes et possibles permet d’envisager des solutions techniques et de dégager les questions de recherche et d’expérimentation à privilégier

Describing the possible climate changes in France and some examples of their effects on main crops used in livestock systems

The effects of climate change on forage and crop production are an important question for the farmers and more largely for the food security in the world. Estimating the effect of climate change on agricultural production needs the use of two types of tools: a model to estimate changes in national or local climates and an other model using climatic data to estimate the effects on vegetation. In this paper, we will mainly present the effects of climate change on climatic features, the variability of criteria influencing crop production in various regions of France and some possible effects on crops

Modeling climate change effects on the potential production of French plains forests at the sub-regional level

International audienceWe modeled the effects of climate change and two forest management scenarios on wood production and forest carbon balance in French forests using process-based models of forest growth.We combined data from the national forest inventory and soil network survey, which were aggregated over a 50 × 50-km grid, i.e., the spatial resolution of the climate scenario data. We predicted and analyzed the climate impact on potential forest production over the period 1960–2100. All models predicted a slight increase in potential forest yield until 2030– 2050, followed by a plateau or a decline around 2070–2100, with overall, a greater increase in yield in northern France than in the south. Gross and net primary productivities were more negatively affected by soil water and atmospheric water vapor saturation deficits in western France because of a more pronounced shift in seasonal rainfall from summer to winter. The rotation-averaged values of carbon flux and production for different forest management options were estimated during four years (1980, 2015, 2045 and 2080). Predictions were made using a two-dimensional matrix covering the range of local soil and climate conditions. The changes in ecosystem fluxes and forest production were explained by the counterbalancing effect of rising CO2 concentration and increasing water deficit. The effect of climate change decreased with rotation length from short rotations with high production rates and low standing biomasses to long rotations with low productivities and greater standing biomasses. Climate effects on productivity, both negative and positive, were greatest on high fertility sites. Forest productivity in northern France was enhanced by climate change, increasingly from west to east, whereas in the southwestern Atlantic region, productivity was reduced by climate change to an increasing degree from west to east

Modelling the regional impacts of climate change on wood production and carbon storage in the plains French forests : results from the CARBOFOR project

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Modelling as a forest management decision tool in response to climate change regional impacts of climate change on wood production and carbon storage in temperate forests

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Agroclimatic conditions in Europe under climate change

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