Baobab (Adansonia digitata)

Conservation and sustainable use of genetic resources of priority food tree species in sub-Saharan AfricaConservation et utilisation durable des ressources génétiques des espèces ligneuses alimentaires prioritaires de l'Afrique subsaharienneLa publicación de esta hoja divulgativa ha sido financiada con la acción complementaria nº AC-2008-00050-00-00, titulada "Publicación de hojas divulgativas: Uso y gestión sostenible y conservación de especies forestales para la alimentación (ELA) en Africa Subsahariana" solicitada por el Centro de Investigación y Tecnología Agroalimentaria de Aragón (CITA), investigador responsable: Eduardo Notivo

Local knowledge on the uses, habitat, and change in abundance of multipurpose mimusops species in Benin

Multipurpose NTFP species typically experience higher harvest demand because of their multiple uses, which, when combined with unsustainable land use practices, may threaten population viability. We assessed local knowledge on the uses, habitat, and population status of Mimusops andongensis and Mimusops kummel, both multipurpose NTFP species in Benin, to promote their valorization and conservation and thus sustain local knowledge on their uses for domestication issues. One hundred households were randomly selected for structured interviews for M. andongensis and 500 for M. kummel. The relationship between age, sex, and ethnic groups and the species uses was assessed using comparison and correspondence analyses. Nearly all organs of the species were used. Both species were mainly exploited for medicinal purposes but also in construction and as firewood. We found similarities in some uses of the species organs, although the species occur in different ecological zones and are used by different ethnic groups. This result should be considered for the valorization of the species. Most informants reported that populations of M. andongensis were decreasing, although some felt that they were increasing, whereas less than one-third said that M. kummel was decreasing. There were strong relationships between gender, age, and ethnic affiliation of the users and the exploited organs of both species. Potential uses exist based on both the past and current uses of the species and in comparison to other countries where they are exploited. Local ethnoecological knowledge and practices will help to valorize and conserve the species. However, further research on the species’ seed germination and propagation ability are also necessary

Physico-chemical properties of crude oil of Khaya senegalensis (Desr.) A. Juss according to bioclimatic zones in Chad

The mature seeds of Khaya senegalensis are from 2 to 2.5 cm long and weigh 289 g per 1000 seeds. These seeds contain about 67% oil by weight. This oil, which is fairly rich in oleic acid (66%), is used in West Africa for cooking, for cosmetics, as an insecticide and in traditional medicine. Prospecting to enhance the development of this oil in Chad, the present study aims to determine the physico-chemical properties of this oil according to bioclimatic zones. The density, acidity, peroxide value, moisture content and percentage of impurities were the parameters studied. The results showed that the crude oil of the seeds of K. senegalensis has the qualities close to those of other edible oils. The study also revealed that climate has influenced the physico-chemical parameters of this oil. Further and more research investigations are necessary to guide decisions on the valorisation and large-scale production of this oil. Keywords: Khaya senegalensis, seed crude oil, physico-chemical parameters, valorisation, bioclimatic zone, Cha

Impact of Climate Change on Priority Plant Species Conservation in The Forests Under ONAB (the National Wood Office of Benin) Management

The sustainable conservation of forest resources in a context of climate change and population growth would be compromised in their current form of exploitation by rural communities. The objective of this study is to assess the impact of climate change on the dynamics of habitats favorable to species of conservation priority in the forests under ONAB management as these species are heavily used by the populations living along the shores of these forests. The study will consist of: Khaya senegalensis, Afzelia africana, Khaya grandifoliola, Pterocarpus erinaceus, Anogeissus leiocarpa, Milicia excelsa, Albizia zygia, Vitex doniana, Antidesma laciniatum and Bombax costatum. Techniques based on the principle of maximum entropy (Maxent) combined with GIS were used to project the favorable habitats of these ten species under current and future climatic conditions (Horizon 2050). Species occurrence data were collected and combined with bioclimatic data derived from the Worldclim database and the edaphic (soil) variable. Two climate models were used for future projections (CNRM-CM5, HadGEM-ES models) under the IPCC A2 scenario, and the partial ROC approach was used for the evaluation of the predictions of ecological niche models. Variables such as cec2 (cation exchange capacity, horizon 5-15cm), bio17 (precipitation of the driest quarter), bio12 (annual precipitation), bio3 (isothermality), bio6 (minimum temperature of the coldest month) and bio7 (annual thermal amplitude) were found to be the most relevant respectively for the distribution of Khaya grandifoliola, Albizia zygia, Anogeissus leiocarpa, Antidesma laciniatum, Afzelia africana and Khaya senegalensis. Under current conditions, only 7% of the Beninese territory would be very favorable to the conservation of Khaya senegalensis and the CNRM-CM5 model predicts an increase of 27.5% and 13.2% respectively of these very favorable and moderately favorable areas by 2050 through conversion of unfavorable areas (7.4%). On the other hand, this model predicts an opposite trend at the level of Afzelia africana where it predicts a decrease of 8.1% and 1.8% respectively of the very favorable and moderately favorable areas and an increase of 5.1% of the unfavorable areas. Ecological niche modeling has basically revealed the conversion of some currently unfavorable habitats into very favorable habitats for conservation (this is the case of Khaya grandifoliola, Khaya senegalensis and Vitex doniana) and the extension of some habitats unfavorable to conservation (Anogeissus leiocarpa, Bombax costatum, and Pterocarpus erinaceus) by 2050. This study provides scientific support for planning and is a decision support tool for the conservation of these species at the socio-economic level

Climate-Smart Agriculture In Benin: Need Assessment Report

Agriculture in Africa must undergo a major transformation in the coming decades in order to meet the interrelated challenges of achieving food security, reducing poverty, and addressing climate change without depleting the natural resource base. Although agriculture is an important part of Africa's economy, employing more than 60% of the population and contributing between 25% and 34% of GDP, productivity is low and food insecurity is high. Currently, about 48% of Africa's population, or approximately 450 million people, live in extreme poverty on less than US$1.25 per day; 63% of the continent's poor live in rural areas and depend on agriculture for their livelihoods (World Bank, 2015). At the same time, the continent is experiencing rapid population growth and urbanization. Half of the projected 2.4 billion increase in the world's population between 2013 and 2050 will occur in sub-Saharan Africa (SSA), and 56 percent of Africa's population is expected to live in urban areas by 2025 (UNODAES, 2013 and 2014). Meeting future food demand will require a large increase in supply. With these challenges, agricultural practices on the African continent cannot continue as usual. African agriculture must therefore transform itself to improve food and nutrition security for an expanding population and to provide a basis for economic growth and poverty. reduction

Local knowledge, pattern and diversity of use of <it>Sclerocarya birrea</it>

Abstract Background Growing interest is on food tree species in general, and particularly indigenous fruit tree species in developing countries since they are inherent to most tropical landscapes and serve the dual function of local livelihood support and biodiversity conservation. It is therefore relevant to assess the level of integration of these species in local cultures and the factors affecting them. This study aims at assessing knowledge and uses of Sclerocarya birrea subsp. birrea and factors affecting the use values within and between communities. Methods This study combines quantitative and qualitative ethnobotanical approaches to investigate uses and factors affecting the use value of S. birrea subsp. birrea. Nine group discussions as well as 161 individual interviews were held in the dry and typical Sudanian zones. Seven different ethnic groups were involved and the survey focused on local uses and perception of factors affecting the dynamics of S. birrea. Results The species has a multitude of uses; all organs are used for more than 20 different purposes. The study highlights how gender, local availability, ethnicity and community location interact to influence the utilization value of the species. People living in drier areas with high occurrence of the S. birrea use it more than those living in wetter areas with low occurrence. While domestic and subsistence uses do not appear to threaten the species, carving, clearing and drought stand out as the major causes of its decline. Conclusions Many factors and their interactions influence the use pattern of the species within and between communities. When compared to the level of exploitation of S. birrea subsp. caffra in southern Africa, the subspecies birrea is at this point relatively underutilized. A high commercial potential exists due to its simple propagation ability and makes it an interesting agroforestry resource.</p

Seasonal variation of environment and conspecific density-dependence effects on early seedling growth of a tropical tree in semi-arid savannahs

Different mechanisms have been proposed to explain species coexistence and maintainance of local species diversity in tree communities. Among the proposed mechanisms, negative density dependence theory (NDD) predicts that seedling growth rate declines at high conspecific densities. However, local environmental conditions and seasonality may also modulate the strength of NDD. We used data from dry and wet seasons in West African semi-arid savannas to explore the importance of NDD and environmental heterogeneity in predicting seedling growth of Afzelia africana Sm, a threatened species with high economic and cutural values. First, we analysed variation of seedling growth in dry and wet seasons, and between vegetation types (tree and shrub savannas). Next, we assessed the effects of environmental heterogeneity (soil type, slope and elevation) and biotic factors (conspecific/heterospecific seedling and adult densities, leaf fungal infection, herbivory) on seedling growth in dry and wet seasons, while controlling for initial seedling size. We predicted that seedling growth would be higher in the wet than in the dry season, and in shrub savannas than in tree savannas due to variation in stand density and intensity of competitive biotic interactions. We also hypothesized that slope and negative density dependence would influence seedling growth and that, the density-dependent effects would vary with environmental heterogeneity and seasonality. Results showed two distinct patterns of seedling growth primarily driven by seasonality: a higher growth rate in the wet season due to water availability and a smaller growth rate during the dry season, possibly because seedlings develop adaptation to drought and fire at the expense of their growth. Growth rate was also higher on flat and gentle slope. Density-dependent effects on seedling growth were only observed with conspecific adults. Seasonality modulated the strength of the density-dependent effect, which was significantly negative in the wet season and nonsignificant in the dry season. This study suggests that A. africana early seedling growth is modulated by interacting effects of seasonality, terrain slope and adult conspecific density. Campaigns for reforestation with A. africana in the semi-arid areas will require increased attention on the seedlings during the long periods of drought