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Scheiter S.,Biodiversitat und Klima Forschungszentrum BiK F | Savadogo P.,Institute Of Lenvironnement Et Of Recherches Agricoles | Savadogo P.,International Center for Research in Agroforestry
Ecological Modelling

The welfare of people in the tropics and sub-tropics strongly depends on goods and services that savanna ecosystems supply, such as food and livestock production, fuel wood, and climate regulation. Flows of these services are strongly influenced by climate, land use and their interactions. Savannas cover c. 20% of the Earth's land surface and changes in the structure and dynamics of savanna vegetation may strongly influence local people's living conditions, as well as the climate system and global biogeochemical cycles. In this study, we use a dynamic vegetation model, the aDGVM, to explore interactive effects of climate and land use on the vegetation structure and distribution of West African savannas under current and anticipated future environmental conditions. We parameterized the model for West African savannas and extended it by including sub-models to simulate fire management, grazing, and wood cutting. The model projects that under future climate without human land use impacts, large savanna areas would shift toward more wood dominated vegetation due to CO2 fertilization effects, increased water use efficiency and decreased fire activity. However, land use activities could maintain desired vegetation states that ensure fluxes of important ecosystem services, even under anticipated future conditions. Ecosystem management can mitigate climate change impacts on vegetation and delay or avoid undesired vegetation shifts. The results highlight the effects of land use on the future distribution and dynamics of savannas. The identification of management strategies is essential to maintain important ecosystem services under future conditions in savannas worldwide. © 2016 Elsevier B.V. Source

Bayala J.,World Agroforestry Center | Sanou J.,Institute Of Lenvironnement Et Of Recherches Agricoles | Teklehaimanot Z.,Bangor University | Kalinganire A.,World Agroforestry Center | Ouedraogo S.J.,Institute du Sahel INSAH
Current Opinion in Environmental Sustainability

In the Sahelian zone of West Africa, crops grown under a discontinuous cover of scattered trees dominate many landscapes and constitute the so-called parklands. These systems reflect the ecological knowledge of the farmers of such risk prone environments. Agroforestry parklands are playing an important role, through trees and shrubs providing soil cover that reduces erosion and buffers the impacts of climate change. They also provide green fodder that complements crop residues for livestock feeds, and fruits and leaves for human consumption and for income generation. The interactions between various components of the system influence the ecosystem service functions of trees of parklands (provisioning, regulating and supporting services) in several ways. These ecosystem functions have been at the center of the local ecological knowledge guiding the management options of the farmers and have also attracted the attention of scientists. Findings revealed new challenges that call for production options ensuring increased and diversified productivity of the systems while preserving the environment. Research on such challenges must adopt an inclusive approach based on local knowledge supported by science-based analyses of the socio-ecological systems in the face of high population pressure and climate change. © 2013 Elsevier B.V. Source

Agency: Cordis | Branch: FP7 | Program: CP-FP-SICA | Phase: ENV.2010.3.1.1-4 | Award Amount: 2.62M | Year: 2011

WAHARA will take a transdisciplinary approach to develop innovative, locally adapted water harvesting solutions with wider relevance for rainfed Africa. Water harvesting technologies play a key role in bringing about an urgently needed increase in agricultural productivity, and to improve food and water security in rural areas. Water harvesting technologies enhance water buffering capacity, contributing to the resilience of African drylands to climate variability and climate change, as well as to socio-economic changes such as population growth and urbanisation. To ensure the continental relevance of project results, research will concentrate on four geographically dispersed study sites in Tunisia, Burkina Faso, Ethiopia and Zambia, covering diverse socio-economic conditions and a range from arid to sub-humid climates. The project emphasizes: i) participatory technology design, i.e. selecting and adapting technologies that have synergies with existing farming systems and that are preferred by local stakeholders, yet tap from a global repertoire of innovative options; ii) sustainable impact, i.e. technologies that combine multiple uses of water, green and blue water management, and integrated water and nutrient management. Using models, water harvesting systems will be designed for maximum impact without compromising downstream water-users, contributing to sustainable regional development; iii) integration and adaptability, i.e. paying attention to the generic lessons to be learned from local experiences, and developing guidelines on how technologies can be adapted to different conditions; and iv) learning and action, i.e. a strategy will be developed to enable learning and action from successes achieved locally: a. within a region, to upscale from water harvesting technologies to water harvesting systems, and b. across regions, promoting knowledge exchange at continental scale.

Institute Of Lenvironnement Et Of Recherches Agricoles and CIRAD - Agricultural Research for Development | Date: 2011-05-26

The invention provides a composition for the inoculation in a plant of agrobacteria transfected by expression vectors, in order to produce in said plant a protein of interest or a derivative of said protein, by deletion or by mutation, characterised in that it comprises

Saiz G.,University of St. Andrews | Saiz G.,James Cook University | Bird M.I.,James Cook University | Domingues T.,University of Edinburgh | And 10 more authors.
Global Change Biology

We examine the influence of climate, soil properties and vegetation characteristics on soil organic carbon (SOC) along a transect of West African ecosystems sampled across a precipitation gradient on contrasting soil types stretching from Ghana (15°N) to Mali (7°N). Our findings derive from a total of 1108 soil cores sampled over 14 permanent plots. The observed pattern in SOC stocks reflects the very different climatic conditions and contrasting soil properties existing along the latitudinal transect. The combined effects of these factors strongly influence vegetation structure. SOC stocks in the first 2 m of soil ranged from 20 Mg C ha -1 for a Sahelian savanna in Mali to over 120 Mg C ha -1 for a transitional forest in Ghana. The degree of interdependence between soil bulk density (SBD) and soil properties is highlighted by the strong negative relationships observed between SBD and SOC (r 2> 0.84). A simple predictive function capable of encompassing the effect of climate, soil properties and vegetation type on SOC stocks showed that available water and sand content taken together could explain 0.84 and 0.86 of the total variability in SOC stocks observed to 0.3 and 1.0 m depth respectively. Used in combination with a suitable climatic parameter, sand content is a good predictor of SOC stored in highly weathered dry tropical ecosystems with arguably less confounding effects than provided by clay content. There was an increased contribution of resistant SOC to the total SOC pool for lower rainfall soils, this likely being the result of more frequent fire events in the grassier savannas of the more arid regions. This work provides new insights into the mechanisms determining the distribution of carbon storage in tropical soils and should contribute significantly to the development of robust predictive models of biogeochemical cycling and vegetation dynamics in tropical regions. © 2012 Blackwell Publishing Ltd. Source

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