About 20% of French emissions of greenhouse gases (GHG) originate from the agricultural sector. Ten technical measures, split into 26 sub-measures, were proposed to reduce GHG emissions from French ...agriculture over the period 2010-2030. Their abatement potential and cost for the farmer werecompared. The proposed measures were linked to nitrogen management, management practices whichincrease carbon storage in soils and biomass, livestock diets and energy production and consumptionon farms. The overall abatement potential can be broken down into three parts. One third of thecumulated abatement potential corresponds to sub-measures with a negative technical cost. These submeasuresare based on an improved efficiency of inputs like N fertilizers, animal feed and energy. Thesecond part corresponds to sub-measures with a moderate cost (<€25 per metric ton of CO2e avoided).These sub-measures require specific investments or modifying the cropping system slightly more, butadditional costs or lower incomes are partially compensated for by a reduction in other costs oradditional marketable products. The third part corresponds to sub-measures with a high cost (>€25 permetric ton of CO2e avoided). These sub-measures require investment with no direct financial return, thepurchase of specific inputs, dedicated labour time or involve greater production losses.
Environ 20% des émissions françaises de gaz à effet de serre (GES) proviennent du secteur agricole.Dix actions portant sur des pratiques agricoles, décomposées en 26 sous-actions, ont été identifiéespour réduire les émissions de l'agriculture en France métropolitaine à l'horizon 2030. Leur potentield'atténuation et leur coût pour l'agriculteur ont été chiffrés et comparés. Ces actions portent sur lagestion de l'azote, les pratiques permettant d'accroitre le stockage de carbone dans les sols et labiomasse, l'alimentation animale et la production et la consommation d'énergie sur l'exploitation. Untiers du potentiel global d'atténuation est à coût négatif, c’est-à-dire avec un gain pour l’agriculteur. Ils'agit d'actions portant sur l'optimisation des intrants (engrais azotés, aliments animaux, énergie). Undeuxième tiers est à coût modéré (<25€ par tonne de CO2e évité). Ces actions nécessitent desinvestissements ou modifient les systèmes de culture, mais les coûts sont partiellement compensés pardes baisses de charge ou produits supplémentaires. Le troisième tiers est à coût plus élevé (>25€ partonne de CO2e évité). Il s'agit d'actions nécessitant des investissements ou achats d'intrants spécifiquessans retour financier, du temps de travail dédié ou entrainant des pertes de production plusimportantes.
This paper addresses the question of summer cover crop adoption by farmers in presence of a risk of yield loss due to take-all disease and climate variability. To analyse the public incentives needed ...to encourage farmers to adopt summer cover crops as a means of reducing N leaching, we combine outputs from an economic, an epidemiological and an agronomic model. The economic model is a simple model of choice under uncertainty. The farmer is assumed to choose among a range of summer fallow managements
and input uses on the basis of the expected utility criterion (HARA assumption) in presence of both climate and take all risks. The epidemiological model proposed by Ennaïfar et al. 1 is used to determine the impact of take all on yields and N-uptake. The crop-soil model (STICS) is used to compute yield developments and N-leaching under various management options and climatic conditions. These models are calibrated to match the conditions prevailing in Grignon, located in the main wheat-growing area in France. Eight management systems are examined: 4 summer fallow managements: ’wheat volunteers’ (WV), ’bare soil’ (BS), ’early mustard’ (EM), ’late mustard’ (LM), and 2 input intensities. We show that the optimal systems are BS (WV) when the take-all risk is (not) taken into account by agents. We then compute the minimum payment to each system such that it emerges in the optimum. We thus derive the required amounts of transfer needed to trigger catch crop adoption. The results of the Monte Carlo sensitivity analysis show that the ranking of management systems is robust over a wide range of input parameters.
The X-ray Integral Field Unit (X-IFU) for Athena Ravera, Laurent; Barret, Didier; Duband, Lionel ...
NASA Center for AeroSpace Information (CASI). Conference Proceedings,
07/2014
Conference Proceeding
Athena is designed to implement the Hot and Energetic Universe science theme selected by the European Space Agency for the second large mission of its Cosmic Vision program. The Athena science ...payload consists of a large aperture high angular resolution X-ray optics (2 m2 at 1 keV) and twelve meters away, two interchangeable focal plane instruments: the X-ray Integral Field Unit (X-IFU) and the Wide Field Imager. The X-IFU is a cryogenic X-ray spectrometer, based on a large array of Transition Edge Sensors (TES), oering 2.5 eV spectral resolution, with approximately 5" pixels, over a field of view of 5' in diameter. In this paper, we present the X-IFU detector and readout electronics principles, some elements of the current design for the focal plane assembly and the cooling chain. We describe the current performance estimates, in terms of spectral resolution, effective area, particle background rejection and count rate capability. Finally, we emphasize on the technology developments necessary to meet the demanding requirements of the X-IFU, both for the sensor, readout electronics and cooling chain.
(abridged) A complete census of planetary systems around a volume-limited sample of solar-type stars (FGK dwarfs) in the Solar neighborhood with uniform sensitivity down to Earth-mass planets within ...their Habitable Zones out to several AUs would be a major milestone in extrasolar planets astrophysics. This fundamental goal can be achieved with a mission concept such as NEAT - the Nearby Earth Astrometric Telescope. NEAT is designed to carry out space-borne extremely-high-precision astrometric measurements sufficient to detect dynamical effects due to orbiting planets of mass even lower than Earth's around the nearest stars. Such a survey mission would provide the actual planetary masses and the full orbital geometry for all the components of the detected planetary systems down to the Earth-mass limit. The NEAT performance limits can be achieved by carrying out differential astrometry between the targets and a set of suitable reference stars in the field. The NEAT instrument design consists of an off-axis parabola single-mirror telescope, a detector with a large field of view made of small movable CCDs located around a fixed central CCD, and an interferometric calibration system originating from metrology fibers located at the primary mirror. The proposed mission architecture relies on the use of two satellites operating at L2 for 5 years, flying in formation and offering a capability of more than 20,000 reconfigurations (alternative option uses deployable boom). The NEAT primary science program will encompass an astrometric survey of our 200 closest F-, G- and K-type stellar neighbors, with an average of 50 visits. The remaining time might be allocated to improve the characterization of the architecture of selected planetary systems around nearby targets of specific interest (low-mass stars, young stars, etc.) discovered by Gaia, ground-based high-precision radial-velocity surveys.
This paper addresses the question of summer cover crop adoption by farmers in presence of a risk of yield loss due to take-all disease and climate variability. To analyse the public incentives needed ...to encourage farmers to adopt summer cover crops as a means of reducing N leaching, we combine outputs from an economic, an epidemiological and an agronomic model. The economic model is a simple model of choice under uncertainty. The farmer is assumed to choose among a range of summer fallow managements and input uses on the basis of the expected utility criterion (HARA assumption) in presence of both climate and take all risks. The epidemiological model proposed by Ennaïfar et al. (2007) is used to determine the impact of take all on yields and N-uptake. The crop-soil model (STICS) is used to compute yield developments and N-leaching under various management options and climatic conditions. These models are calibrated to match the conditions prevailing in Grignon, located in the main wheatgrowing area in France. Eight management systems are examined: 4 summer fallow managements: 'wheat volunteers' (WV), 'bare soil' (BS), 'early mustard' (EM), 'late mustard' (LM), and 2 input intensities. We show that the optimal systems are BS (WV) when the take-all risk is (not) taken into account by agents. We then compute the minimum payment to each system such that it emerges in the optimum. We thus derive the required amounts of transfer needed to trigger catch crop adoption. The results of the Monte Carlo sensitivity analysis show that the ranking of management systems is robust over a wide range of input parameters.
This paper addresses the question of summer cover crop adoption by farmers in presence of a risk of yield loss due to take-all disease and climate variability. To analyse the public incentives needed ...to encourage farmers to adopt summer cover crops as a means of reducing N leaching, we combine outputs from an economic, an epidemiological and an agronomic model. The economic model is a simple model of choice under uncertainty. The farmer is assumed to choose among a range of summer fallow managements and input uses on the basis of the expected utility criterion (HARA assumption) in presence of both climate and take all risks. The epidemiological model proposed by Ennaïfar et al. 1 is used to determine the impact of take all on yields and N-uptake. The crop-soil model (STICS) is used to compute yield developments and N-leaching under various management options and climatic conditions. These models are calibrated to match the conditions prevailing in Grignon, located in the main wheat-growing area in France. Eight management systems are examined: 4 summer fallow managements: 'wheat volunteers' (WV), 'bare soil' (BS), 'early mustard' (EM), 'late mustard' (LM), and 2 input intensities. We show that the optimal systems are BS (WV) when the take-all risk is (not) taken into account by agents. We then compute the minimum payment to each system such that it emerges in the optimum. We thus derive the required amounts of transfer needed to trigger catch crop adoption. The results of the Monte Carlo sensitivity analysis show that the ranking of management systems is robust over a wide range of input parameters.
This paper addresses the question of summer cover crop adoption by farmers in presence of a risk of yield loss due to take-all disease and climate variability. To analyse the public incentives needed ...to encourage farmers to adopt summer cover crops as a means of reducing N leaching, we combine outputs from an economic, an epidemiological and an agronomic model. The economic model is a simple model of choice under uncertainty. The farmer is assumed to choose among a range of summer fallow managements and input uses on the basis of the expected utility criterion (HARA assumption) in presence of both climate and take all risks. The epidemiological model proposed by Ennaïfar et al. 1 is used to determine the impact of take all on yields and N-uptake. The crop-soil model (STICS) is used to compute yield developments and N-leaching under various management options and climatic conditions. These models are calibrated to match the conditions prevailing in Grignon, located in the main wheat-growing area in France. Eight management systems are examined: 4 summer fallow managements: ’wheat volunteers’ (WV), ’bare soil’ (BS), ’early mustard’ (EM), ’late mustard’ (LM), and 2 input intensities. We show that the optimal systems are BS (WV) when the take-all risk is (not) taken into account by agents. We then compute the minimum payment to each system such that it emerges in the optimum. We thus derive the required amounts of transfer needed to trigger catch crop adoption. The results of the Monte Carlo sensitivity analysis show that the ranking of management systems is robust over a wide range of input parameters.
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