Copyright 2020 - copyright UMR ESPACE-DEV - 2017

Caribcoast : un réseau caribéen pour la prévention et la gestion de crise des risques littoraux en lien avec le changement climatique

Le 2ème comité de pilotage du projet INTERREG CARIB-COAST s’est déroulé du 8 au 10 octobre 2019 à Kingston en Jamaïque. L’avancement des travaux du WP3 (Réseau de suivi de l’érosion côtière et techniques de mitigation) porté par l’ONF de Guadeloupe a été discuté avec les partenaires locaux et internationaux du projet. Dans ce WP, l’IRD (UMR Espace-Dev) est responsable du volet dédié à la cartographie des écosystèmes de mangroves, récifs coralliens et herbiers par des méthodes d’observation de la Terre. Auréa Pottier et Thibault Catry, experts en télédétection au sein d’Espace-Dev, ont présenté des résultats de cartographie des mangroves dans les 6 sites du projet (Guadeloupe, Martinique, Saint Martin, Jamaïque, Trinidad et Tobago, Porto Rico) à partir d’image satellite Sentinel 2 à 10 m de résolution, qui ont permis la mise à jour des connaissances sur la distribution et l’extension de cet écosystème (figure 1).

Dans la suite des travaux, ces cartes seront validées en intégrant les connaissances de terrain des partenaires locaux et les états de santé des écosystèmes seront étudiés via la production d’indicateurs basés sur des images satellite très haute résolution (Pléiades, SPOT 6/7, Planets). Une formation à l’utilisation des images Sentinel 2 pour réaliser ces cartographies a également été organisée pour les partenaires du projet durant ce comité de pilotage.

Le prochain comité de pilotage du projet CARIBCOAST devrait se dérouler en mars 2020 à Porto Rico.

 

caribcoast

Figure 1 : Cartographie de la distribution des mangroves de la Jamaïque (en rouge) réalisée à partir d’une image Sentinel 2 à 10 m de résolution (Novembre 2018, ©ESA), avec un zoom sur la zone de Peake bay.

 

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Save the date ! Les sciences humaines et sociales dans les aires marines protégées

 

Capture decran 2019 11 21 a 11.40.29


3-5 février 2020 - Plouzané

L'Agence française pour la biodiversité1 et le GIS HomMer2 organisent à Plouzané (Pôle numérique Brest Iroise) un séminaire réunissant gestionnaires d'aires marines protégées (AMP) et chercheurs en sciences humaines et sociales (SHS).

Objectifs
: Partager nos questionnements et réfléchir ensemble à une feuille de route scientifique "Mer et SHS" en appui à la gestion des AMP.
Thématiques : Pleine naturalité, rapports hommes-natures, médiation, paysages (sous-)marins, « patrimoine culturel » , pêche et aires protégées ... seront quelques unes des thématiques abordées.

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Symposium de recherche sur santé à la triple frontière entre le Brésil, la Colombie et le Pérou

SAUDETRIFRON NOV2019 PT

 

27-29 novembre - Tabatinga

Le Symposium vise à promouvoir une rencontre scientifique interinstitutionnelle destinée aux chercheurs et aux professionnels de la santé, étudiants de premier cycle et troisième cycle, afin de diffuser les recherches scientifiques en santé réalisées à la frontière et d'encourager la création d'un réseau de chercheurs en santé de la triple frontière. Le chercheur Emmanuel Roux (UMR Espace-Dev) participera à l'événement.

S'incrire sur le site de l'événément
(inscription gratuite)

Atelier sur la séquestration du carbone

Le programme structurant interdisciplinaire et partenarial sur la séquestration continentale du carbone de l’IRD (PSIP-Seq2C) souhaite contribuer à repousser les fronts de sciences et lever les verrous liés à l’objectif Capture decran 2019 11 13 a 11.14.37d’augmentation de la Seq2C afin d’identifier des systèmes séquestrants viables et équitables dans le temps et l’espace, faciliter leur déploiement dans les territoires, encourager la co construction d’actions au Sud à fort impact social et mieux articuler Science, Politiques Publiques (PPs) et Société civile.

Après un premier atelier sur la séquestration du carbone (C) dans les sols, les biomasses végétaleset les eaux continentales à Montpellier en 2018, spécifiques aux enjeux scien-tifiques, un second atelier s’est tenu le 7  octobre 2019 à Dakar, avec un focus sur l’appui aux Politique publiques et aux territoires en matière de Seq2C dans la région sahélienne. Ce dernier s’est déroulé en amont de la Conférence Intensification Durable – CID 2019 avec le soutien du département ECOBIO, de la MP2I, de la représentation IRD au Sénégal et de l’UMR Espace-dev.

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Photo : Prélèvements de racines de niébé pour analyse par deux étudiants thésards, à Diohine, Sénégal. ©IRD

Nos dernières publications

icone documentation publication

Probabilistic cellular automata are extended stochastic systems, widely used for modelling phenomena in many disciplines. The possibility of controlling their behaviour is therefore an important topic. We shall present here an approach to the problem of controlling such systems by acting only on the boundary of a target region. In particular we are interested in optimal control, which is rather demanding in computational terms, so we present also a less demanding suboptimal method. Finally, we present an example of optimal control with avoidance.

Affiliation IRD : UMR 228 (ESPACE-DEV) - Copublication Sud avec : Mexique

The article analyses urban projects and governance of urban planning in a fast growingurban community (Grand Narbonne, Aude, France), focusing on the approach of the local stakeholders, between interest and distrust, about landscape considered as a dimension of the urban project and as a tool for collective thinking about urban planning. Trying to overcome what appears to be a sort of consensus about the importance of the landscape dimension due to the European Landscape Convention and to the evolution of the French legislative framework, the paper tries to highlight the processes of emergence and diffusion of a collective "culture of landscape" applied to urban planning. The part played in these processes by the regional natural park of the "Narbonnaise en Mediterranee" is thoroughly analysed, as well as the limits of its actions. The study also takes into account the strengthening of the intercommunal institutions, which broadens the local system of governance.

Affiliation IRD : UMR 228 (ESPACE-DEV) - Lien Horizon FDI
Descr. géo. Horizon : MEDITERRANEE ; NARBONNAISE PARC

Amazonian floodplains form complex hydrological networks that play relevant roles in global biogeochemical cycles, and bacterial degradation of the organic matter in these systems is key for regional carbon budget. The Amazon undergoes extreme seasonal variations in water level, which produces changes in landscape and diversifies sources of organic inputs into floodplain systems. Although these changes should affect bacterioplankton community composition (BCC), little is known about which factors drive spatial and temporal patterns of bacterioplankton in these Amazonian floodplains. We used high-throughput sequencing (Illumina MiSeq) of the V3-V4 region of the 16S rRNA gene to investigate spatial and temporal patterns of BCC of two size fractions, and their correlation with environmental variables in an Amazon floodplain lake (Lago Grande do Curuai). We found a high degree of novelty in bacterioplankton, as more than half of operational taxonomic units (OTUs) could not be classified at genus level. Spatial habitat heterogeneity and the flood pulse were the main factors shaping free-living (FL) BCC. The gradient of organic matter from transition zone lake -Amazon River was the main driver for particle-attached (PA) BCC. The BCC reflected the complexity of the system, with more variation in space than in time, although both factors were important drivers of the BCC in this Amazon floodplain system.

Affiliation IRD : UMR 228 (ESPACE-DEV) ; (sans mention d'UMR) - Copublication Sud avec : Brésil - Lien Horizon FDI
Descr. géo. Horizon : BRESIL ; AMAZONE ; GRANDE DO CURUAI LAC

Five case studies are presented, all located in highland regions of South Asia and inhabited by ethnic minorities (India, Nepal, China, Laos, Vietnam), in order to analyze the consequences of narratives, actions and transformations of governance via the landscape. How does the landscape become, through tourism, a "way of seeing" territories, how does it foster renewed governance of these territories? After having shown how the use of landscape resources leads to the development of a landscape culture via tourism, we will see that the landscape occupies various places in the processes of territorial governance. A final typology will be based on three criteria : consciousness of the landscape, governance process, and tourism expansion.

Affiliation IRD : UMR 228 (ESPACE-DEV) ; UMR 215 (Prodig) - Copublication Sud avec : Inde - Lien Horizon FDI
Descr. géo. Horizon : NEPAL ; INDE ; CHINE ; LAOS ; VIET NAM

Built on the basis of a literature review on colonial history, contemporary socio-spatial dynamics and an analysis of the electoral results of the last thirty years in New Caledonia, this article shows the long process that has led to self-determination, following a long period of hard colonization and decolonization in trompe-l'oeil. "Rebalancing", which has been in operation for more than three decades, has difficulty reducing differences between communities in a nickel-dominated territory with an economy suffering from Dutch disease. On 4 November 2018, a small and unprecedented electorate was asked the following question: "Do you want New Caledonia to achieve full sovereignty and become independent?". Although broad, the victory of the "No" by 56.7% against 43.3% for the "Yes" is closer than expected and it was the independentists who gave the impression that they had won this referendum. The spatial distribution of the "Yes" and "No" is the copy of the distribution of Kanak and Europeans, revealing the deep divisions of this society.

Affiliation IRD : UMR 228 (ESPACE-DEV)

Reservoirs are closely related to anthropic activities, and quantifying the long-term dynamics of surface water in reservoirs could be useful for decision-makers to improve the actual strategies of reservoir management. This study used the global Moran's I index, modi?ed Normalized Difference Water Index (MNDWI) and a total of 596 Landsat images during 1985-2018 for tracking the annual dynamics of water extent in the process of water shrinkage and expansion in Guanting Reservoir, China. Landscape metrics related to the area, elongation, fragmentation, and edge complexity of surface water in reservoir landscape were computed for tracking the annual dynamics of surface water patterns. Statistical comparison between the results of global Moran's I index and landscape metrics indicates that except for the complexity of water and non-water edge, global Moran's I index can successfully estimate the dynamics of the area, elongation and fragmentation of surface water in the reservoir. This study proposed a continuous approach of long-term monitoring of surface water patterns using spatial autocorrelation that might be used in the areas where the surface water extraction is difficult and water dynamics are complex.

Affiliation IRD : UMR 228 (ESPACE-DEV) - Copublication Sud avec : Brésil ; Chine - Lien Horizon FDI
Descr. géo. Horizon : CHINE ; PEKIN ; GUANTING

Achieving food security goals in West Africa will depend on the capacity of the agricultural sector to feed the rapidly growing population and to moderate the adverse impacts of climate change. Indeed, a number of studies anticipate a reduction of the crop yield of the main staple food crops in the region in the coming decades due to global warming. Here, we found that crop production might have already been affected by climate change, with significant yield losses estimated in the historical past. We used a large ensemble of historical climate simulations derived from an atmospheric general circulation model and two process-based crop models, SARRA-H and CYGMA, to evaluate the effects of historical climate change on crop production in West Africa. We generated two ensembles of 100 historical simulations of yields of sorghum and millet corresponding to two climate conditions for each crop model. One ensemble is based on a realistic simulation of the actual climate, while the other is based on a climate simulation that does not account for human influences on climate systems (that is, the non-warming counterfactual climate condition). We found that the last simulated decade, 2000-2009, is approximately 1 degrees C warmer in West Africa in the ensemble accounting for human influences on climate, with more frequent heat and rainfall extremes. These altered climate conditions have led to regional average yield reductions of 10-20% for millet and 5-15% for sorghum in the two crop models. We found that the average annual production losses across West Africa in 2000-2009 associated with historical climate change, relative to a non-warming counterfactual condition (that is, pre-industrial climate), accounted for 2.33-4.02 billion USD for millet and 0.73-2.17 billion USD for sorghum. The estimates of production losses presented here can be a basis for the loss and damage associated with climate change to date and useful in estimating the costs of the adaptation of crop production systems in the region.

Affiliation IRD : UMR 228 (ESPACE-DEV) - Lien Horizon FDI 
Descr. géo. Horizon : AFRIQUE DE L'OUEST

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