Contribution of agronomy to land management issues - A Comparison of five interdisciplinary PhD theses

An introductory literature review highlights the growing attention within the processes taking place at farming region and landscape scale beside the classical spatial scales at cultivated/experimental plot level. This recent evolution in agronomy finds its origin in newly emerging land management issues. Meanwhile, geography and other disciplines are stressing the need for a greater integration of multifunctional agricultural activities into the decision-making processes at the various levels of land management, such as provinces, municipalities or watersheds. This requires also that studies on farmland management include explicitly the different environmental and social contexts influencing farming activities. In this paper we aim to analyse how recent agronomic oriented research are facing and supporting various land management issues. We have compared five interdisciplinary PhD theses examining their definitions and methods of analysis for: the farming system, the local land management issues at stake, the spatial scale selected for the study, the stakeholders' involvement and the interaction with other disciplines. Common issues which emerged from this comparison are delivery of agro-environmental services, sustainable land management and landscape conservation. Multiple spatial levels were considered, which included at least one administrative unit of policy decision/implementation. Consequently, the explicit (re)definition of some agronomic concepts and methods was needed. Regarding the interdisciplinary framework, the theses have stressed the interactions among agronomy, geography and ecology. All theses aimed at delivering tools for decision-making support, mainly in the form of cartography. Nevertheless the participation of local stakeholders was generally included as a final step; herewith the settings of stakeholders' involvement were various. In conclusion, we discuss how the produced knowledge has enhanced the land management issues in local planning tools. On these bases, we stress finally the issues at stake to strengthen the roles and contributions of agronomic oriented education and research to agricultural land management and development. (Résumé d'auteur

The representation of alkalinity and the carbonate pump from CMIP5 to CMIP6 Earth system models and implications for the carbon cycle

Ocean alkalinity is critical to the uptake of atmospheric carbon in surface waters and provides buffering capacity towards the associated acidification. However, unlike dissolved inorganic carbon (DIC), alkalinity is not directly impacted by anthropogenic carbon emissions. Within the context of projections of future ocean carbon uptake and potential ecosystem impacts, especially through Coupled Model Intercomparison Projects (CMIPs), the representation of alkalinity and the main driver of its distribution in the ocean interior, the calcium carbonate cycle, have often been overlooked. Here we track the changes from CMIP5 to CMIP6 with respect to the Earth system model (ESM) representation of alkalinity and the carbonate pump which depletes the surface ocean in alkalinity through biological production of calcium carbonate and releases it at depth through export and dissolution. We report an improvement in the representation of alkalinity in CMIP6 ESMs relative to those in CMIP5, with CMIP6 ESMs simulating lower surface alkalinity concentrations, an increased meridional surface gradient and an enhanced global vertical gradient. This improvement can be explained in part by an increase in calcium carbonate (CaCO3) production for some ESMs, which redistributes alkalinity at the surface and strengthens its vertical gradient in the water column. We were able to constrain a particulate inorganic carbon (PIC) export estimate of 44–55 Tmol yr−1 at 100 m for the ESMs to match the observed vertical gradient of alkalinity. Reviewing the representation of the CaCO3 cycle across CMIP5/6, we find a substantial range of parameterizations. While all biogeochemical models currently represent pelagic calcification, they do so implicitly, and they do not represent benthic calcification. In addition, most models simulate marine calcite but not aragonite. In CMIP6, certain model groups have increased the complexity of simulated CaCO3 production, sinking, dissolution and sedimentation. However, this is insufficient to explain the overall improvement in the alkalinity representation, which is therefore likely a result of marine biogeochemistry model tuning or ad hoc parameterizations. Although modellers aim to balance the global alkalinity budget in ESMs in order to limit drift in ocean carbon uptake under pre-industrial conditions, varying assumptions related to the closure of the budget and/or the alkalinity initialization procedure have the potential to influence projections of future carbon uptake. For instance, in many models, carbonate production, dissolution and burial are independent of the seawater saturation state, and when considered, the range of sensitivities is substantial. As such, the future impact of ocean acidification on the carbonate pump, and in turn ocean carbon uptake, is potentially underestimated in current ESMs and is insufficiently constrained.</p

Face aux limites de la cartographie de la prospective spatiale et territoriale : cas des blocs-diagrammes des systèmes hydrologiques

International audienceFrom a prospective exercise that aimed at assessing the evolution by 2030 of water resources in France (AQUA 2030 French Ministry of Ecology), several territorial prospective scenarios were conducted. The preservation of aquatic environments and water as well as risks associated with it are the subject of public policies, but their joints with dynamic socio-economic and territorial issues can be complex and difficult to understand. From prospective workshops, scenarios aimed firstly to establish qualitative stories of the evolution of natural and human systems related to water in 2030, and secondly to cartographic representations of these systems territorially, to compare the states and allow debate on the issues. Seven spatial hydrological systems with five future states were built, with a need to represent 42 maps. These seven models have been selected according to their ability to illustrate dynamics and evolutions of the main hydrographical systems and water resource in France. As the seven spatial hydrological systems were chosen as 'ideal types', their cartographic representations encountered some limits. The paper presents these limits and a solution to optimize the spatial representation of these systems, with landscape block diagrams. The landscape block diagram can be defined as a 3D graphic representation of a landscape pattern. If maps are all the time connected to geographical coordinates, the blocks diagram can be not. It becomes an abstraction, a model of several real landscape patterns and ecological systems at different scales. To create a landscaped block diagram means having a degree of abstraction for representing the intermediate reality, both visual (concrete) and synthetic (simplification of forms and volumes, symbolic figure not viewable areas trend modeling). It aims to reflect on what can happen (prospective), not what will happen (forecast). At the spatial scale representations of the human's eye and understanding of landscapes, some punctual landscape components are difficult to read, or cannot be represented on a map. The model realized for this study represents a combination of spatial components describing some specific landscapes and hydrological systems themselves linked with the indicators of the five scenarios from AQUA 2030 report. Seven blocks have been designed as a model of typical French landscapes and 'ideal type' hydrographical system: seacoast and continental wetlands, mountainous areas as head of river basin, urbanized seacoast, urbanized riverside, intensive farming areas on plain, extensive farming systems on piedmont. 42 blocks were created at all: for each system a visualization of today following by 5 scenarios illustrating, ecological and socio-economical impacts or stakes thought landscape patterns and spatial components. The paper discusses how landscape blocks diagrams can be used as tool to compose, discuss, recompose the scenarios of the future water management instead of maps. Landscape visualizations translate a technical vision of indicators into a more sensitive vision of the scenarios understandable by everybody. The block diagram tool can serve as an educational mean in the service of a policy development project because it refers to experiences and practices witch create always new forms of the lands, then new ways to manage and their stakes

Restitution d’une démarche de concertation concernant l’identification des services écosystémiques dans le cadre du projet de Réserve Naturelle Régionale de la Haute Vallée de la Loire

Restitution de l'atelier participatif du 27 novembre 2013 à Chadron (43

Restitution d’une démarche de concertation concernant l’identification des services écosystémiques dans le cadre du projet de Réserve Naturelle Régionale de la Haute Vallée de la Loire

Restitution de l'atelier participatif du 27 novembre 2013 à Chadron (43

Contribution of agronomy to land management issues - A comparison of five PhD thesis

An introductory literature review highlights the growing attention within the processes taking place at farming region and landscape scale beside the classical spatial scales at cultivated/experimental plot level. This recent evolution in agronomy finds its origin in newly emerging land management issues. Meanwhile, geography and other disciplines are stressing the need for a greater integration of multifunctional agricultural activities into the decision-making processes at the various levels of land management, such as provinces, municipalities or watersheds. This requires also that studies on farmland management include explicitly the different environmental and social contexts influencing farming activities. In this paper we aim to analyse how recent agronomic oriented research are facing and supporting various land management issues. We have compared five interdisciplinary PhD theses examining their definitions and methods of analysis for: the farming system, the local land management issues at stake, the spatial scale selected for the study, the stakeholders’ involvement and the interaction with other disciplines. Common issues which emerged from this comparison are delivery of agro-environmental services, sustainable land management and landscape conservation. Multiple spatial levels were considered, which included at least one administrative unit of policy decision/implementation. Consequently, the explicit (re)definition of some agronomic concepts and methods was needed. Regarding the interdisciplinary framework, the theses have stressed the interactions among agronomy, geography and ecology. All theses aimed at delivering tools for decision-making support, mainly in the form of cartography. Nevertheless the participation of local stakeholders was generally included as a final step; herewith the settings of stakeholders’ involvement were various. In conclusion, we discuss how the produced knowledge has enhanced the land management issues in local planning tools. On these bases, we stress finally the issues at stake to strengthen the roles and contributions of agronomic oriented education and research to agricultural land management and development

1.5µm Lidar anemometer for True Air Speed, Angle Of Sideslip and Angle Of Attack measurements onboard Piaggio P180 aircraft

International audienceLidar (Light detection and ranging) is a well established measurement method for the prediction of atmospheric motions through velocity measurements. Recent advances in 1.5µm Lidars show that the technology is mature, offers great ease of use and is reliable and compact. A 1.5µm airborne Lidar appears to be a good candidate for airborne in-flight measurement systems: it allows to measure remotely, outside aircraft aerodynamic disturbance, an absolute air speed (no need of calibration) with a great precision and in all aircraft flight domain. In the frame work of the EU AIM2 project, Onera task has consisted in the development and testing of a 1.5µm anemometer sensor for in-flight airspeed measurements. Objective of this work is to demonstrate that the 1.5µm Lidar sensor can increase the quality of the data acquisition procedure for the aircraft flight test certification. This paper presents the 1.5µm anemometer sensor dedicated to in-flight airspeed measurements and describes the flight tests performed successfully onboard the Piaggio P180. Lidar air data have been graphically compared to the air data provided by the aircraft Flight Test Instrumentation (FTI) in the reference frame of the Iidar sensor head. Very good agreement of True Air Speed (TAS), Angle Of Sideslip (AOS) and Angle Of Attack (AOA) was observed