9 research outputs found
Agroforesterie et services écosystémiques en zone tropicale
Respectueux de lâenvironnement et garantissant une sĂ©curitĂ© alimentaire soutenue par la diversification des productions et des revenus quâils procurent, les systĂšmes agroforestiers apparaissent comme un modĂšle prometteur dâagriculture durable dans les pays du Sud les plus vulnĂ©rables aux changements globaux. Cependant, ces systĂšmes agroforestiers ne peuvent ĂȘtre optimisĂ©s quâĂ condition de mieux comprendre et de mieux maĂźtriser les facteurs de leurs productions. Lâouvrage prĂ©sente un ensemble de connaissances rĂ©centes sur les mĂ©canismes biophysiques et socio-Ă©conomiques qui sous-tendent le fonctionnement et la dynamique des systĂšmes agroforestiers. Il concerne, dâune part les systĂšmes agroforestiers Ă base de cultures pĂ©rennes, telles que cacaoyers et cafĂ©iers, de rĂ©gions tropicales humides en AmĂ©rique du Sud, en Afrique de lâEst et du Centre, dâautre part les parcs arborĂ©s et arbustifs Ă base de cultures vivriĂšres, principalement de cĂ©rĂ©ales, de la rĂ©gion semi-aride subsaharienne dâAfrique de lâOuest. Il synthĂ©tise les derniĂšres avancĂ©es acquises grĂące Ă plusieurs projets associant le Cirad, lâIRD et leurs partenaires du Sud qui ont Ă©tĂ© conduits entre 2012 et 2016 dans ces rĂ©gions. Lâensemble de ces projets sâarticulent autour des dynamiques des systĂšmes agroforestiers et des compromis entre les services de production et les autres services socio-Ă©cosystĂ©miques que ces systĂšmes fournissent
Consommation en eau dâune espĂšce agroforestiĂšre en zone soudanienne
International audienc
Is agroforestry species as efficient as forest species in recycling local rainfall in sudanian belt?
International audienc
Model, satellite and ground-based estimates of evapotranspiration. A comparison in sub-humid tropical West Africa (Benin) within the framework of the ALMIP2 project
International audienc
AMMA-CATCH, a critical zone observatory in West Africa monitoring a megion in transition
International audienceWest Africa is a region in fast transition from climate, demography, and land use perspectives. In this context, the African Monsoon Multidisciplinary Analysis (AMMA)-Couplage de l'Atmosphere Tropicale et du Cycle eco-Hydrologique (CATCH) long-term regional observatory was developed to monitor the impacts of global change on the critical zone of West Africa and to better understand its current and future dynamics. The observatory is organized into three thematic axes, which drive the observation and instrumentation strategy: (i) analyze the long-term evolution of eco-hydrosystems from a regional perspective; (ii) better understand critical zone processes and their variability; and (iii) meet socioeconomic and development needs. To achieve these goals, the observatory has gathered data since 1990 from four densely instrumented mesoscale sites (similar to 10(4) km(2) each), located at different latitudes (Benin, Niger, Mali, and Senegal) so as to sample the sharp eco-climatic gradient that is characteristic of the region. Simultaneous monitoring of the vegetation cover and of various components of the water balance at these four sites has provided new insights into the seemingly paradoxical eco-hydrological changes observed in the Sahel during the last decades: groundwater recharge and/ or runoff intensification despite rainfall deficit and subsequent re-greening with still increasing runoff. Hydrological processes and the role of certain key landscape features are highlighted, as well as the importance of an appropriate description of soil and subsoil characteristics. Applications of these scientific results for sustainable development issues are proposed. Finally, detecting and attributing eco-hydrological changes and identifying possible regime shifts in the hydrologic cycle are the next challenges that need to be faced
AMMA-CATCH, a critical zone observatory in West Africa monitoring a region in transition
West Africa is a region in fast transition from climate, demography, and land use perspectives. In this context, the African Monsoon Multidisciplinary Analysis (AMMA)-Couplage de l'Atmosphere Tropicale et du Cycle eco-Hydrologique (CATCH) long-term regional observatory was developed to monitor the impacts of global change on the critical zone of West Africa and to better understand its current and future dynamics. The observatory is organized into three thematic axes, which drive the observation and instrumentation strategy: (i) analyze the long-term evolution of eco-hydrosystems from a regional perspective; (ii) better understand critical zone processes and their variability; and (iii) meet socioeconomic and development needs. To achieve these goals, the observatory has gathered data since 1990 from four densely instrumented mesoscale sites (similar to 10(4) km(2) each), located at different latitudes (Benin, Niger, Mali, and Senegal) so as to sample the sharp eco-climatic gradient that is characteristic of the region. Simultaneous monitoring of the vegetation cover and of various components of the water balance at these four sites has provided new insights into the seemingly paradoxical eco-hydrological changes observed in the Sahel during the last decades: groundwater recharge and/ or runoff intensification despite rainfall deficit and subsequent re-greening with still increasing runoff. Hydrological processes and the role of certain key landscape features are highlighted, as well as the importance of an appropriate description of soil and subsoil characteristics. Applications of these scientific results for sustainable development issues are proposed. Finally, detecting and attributing eco-hydrological changes and identifying possible regime shifts in the hydrologic cycle are the next challenges that need to be faced