Dataverse World Agroforestry (ICRAF)
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Replication data for: Integration of legume trees in maize-based cropping systems improves rain use efficiency and yield stability under rain-fed agriculture
No full textWater availability is a major constraint to crop production in sub-Saharan Africa (SSA) where agriculture is predominantly rain-fed. This study aimed to investigate the effect of the nitrogen-fixing legume tree Leucaena (Leucaena leucocephala) and ino
rganic fertilizer on rain use efficiency (RUE), a robust measure of productivity and land degradation, in three long-term (11–12 years) experiments conducted in Zambia and Nigeria. On the two Zambian sites, sole maize (Zea mays) grown continuously (for 11–12 years) with the recommended fertilizer achieved the highest RUE (3.9–4.6 kg ha−1 mm−1) followed by maize intercropped with Leucaena (2.5–3.4 kg ha−1 mm−1). This translated to 192–383% increase in RUE over the control (maize grown without nutrient inputs), which is the de facto resource-poor farmers’ practice. RUE was more stable in fully fertilized sole maize on the first Zambian site and not statistically different from the maize–Leucaena associations on the second site. On the Nigerian site, RUE was higher in maize planted between Leucaena hedgerows supplemented with 50% of the recommended fertilizer (3.9 kg ha−1 mm−1), maize grown between Leucaena hedgerows without fertilizer (3.0 kg ha−1 mm−1) and sole maize receiving the recommended fertilizer (2.8 kg ha−1 mm−1), which translated to increases in RUE of 202%, 139% and 85%, respectively, over the control. RUE was more stable in the maize grown between Leucaena hedgerows than in the fully fertilized maize. On all sites RUE was least stable in the control. Yield stability in the maize–Leucaena association was not significantly different from the fully fertilized maize on the Zambian sites. On the Nigerian site, maize yields were more stable in maize grown in Leucaena hedgerows than in fully fertilized sole maize. Supplementation of maize grown in Leucaena hedgerows with 50% of the recommended fertilizers resulted in greater yield stability. It is concluded that intercropping cereals with legume trees and supplementation with inorganic fertilizer can increase rain use efficiency and yield stability in rain-fed agriculture in SSA
Agroforestry system and trees survival assessment: case study in K20 and SIKA in the Madina Oula lanscape
No full textAgroforestry system and trees survival assessment: case study in K20 and SIKA in the Madina Oula lanscap
Approche alternative de gestion des ressources naturelles dans le paysage de Madina Oula en Guinée
No full textIl existe une forte pression sur les ressources naturelles dans les paysages tropicaux due aux approches d’intervention peu appropriées et qui sont exacerbées par une pauvreté sans cesse croissante dans les communautés rurales. Se référant aux approches de développement et de gestion participative des ressources, la présente étude vise la mise la conception et l’évaluation d’une nouvelle approche alternative qui permettrait à la fois d’améliorer les conditions de vie des populations des pays ayant beaucoup de ressources naturelles par les innovations agroforestières et préserver durablement la biodiversité dans les paysages. La méthode d’enquête basée sur les grilles d’observation et questionnaires semi-structurés a été utilisée en plus de l’exploitation de la base de données générée par les phases du projet LAMIL en Guinée. Au terme de cette étude, une nouvelle approche alternative dénommée Approche Vision et Initiative Paysanne « AVIP » est développée et testée à Madina Oula. L’analyse sensorielle a mis en évidence l’influence de chaque étape opérationnelle de l’AVIP sur les composantes choisies. L’approche est prouvée robuste même s’il ya besoin de continuer les tests
à large échelle surtout dans les hauts plateaux boisés d’Afrique
Effet du trempage et de la technique de cuisson sur le concassage des graines du Njansang (Rhicinodendron heudelotii)
No full textLâévaluation des procédés traditionnels de décorticage du njansang avait révélés que les techniques traditionnelles dâextraction des amandes demandent beaucoup de temps et une main dâÅuvre importante. Ainsi
, dans le souci de réduire les dépenses énergétiques (réduire la pénibilité) et le temps de concassage, bref alléger la tâche de décorticage, lâICRAF et la GFTI ont conçu la concasseuse de njansang. Le prototype conçu en 2007 avait été introduit dans le village Epkwassong pour expérimentation en milieu réel. Avec toutes ces années dâessai, des questions se posaient encore sur la perception des producteurs par rapport à la machine et la qualité de ces produits, le niveau dâutilisation de la machine, le mode de gestion mis en place pour la gérer, sa performance au concassage, sa rentabilité, les difficultés rencontrées dans son utilisation et ses effets. Cette étude portait à cet effet sur lâanalyse de ces questions et sâest déroulée dans le village pilote dâexpérimentation du prototype Epkwassong. Pour effectuer cette évaluation, trois types de questionnaires ont été structurés : un adressé au concepteur de la machine, un autre aux machinistes et un trois au producteur de njansang (utilisateur et non utilisateur de la machine). Un guide dâentretien a été attribué aux responsables du groupe gestionnaire de la machine et deux fiches de collecte des données ont servis à faire les essais de concassage manuel et mécanisé. Il découle de ce travail que selon les producteurs le recours au concassage mécanisé réduit la pénibilité du travail ainsi que le temps de concassage ; mais la qualité du produit est moins bonne que celle du concassage manuel. Ces perception ont a été confirmées par les résultats des essais de concassage manuel et mécanisé. Le système de gestion mis en place est ce pendant inéquitable et non viable. Le niveau dâutilisation de 25% des producteurs et le nombre dâutilisation à 86,4 % au plus 2 fois restent encore faible. Le recours au concassage mécanisé réduit également les coûts de concassage mais à des niveaux de production annuelle de noix élevés traité à la machine. Il en est de même pour les indicateurs de la rentabilité. Plus la production est grande plus réduit peuvent être les frais de concassage et la VAN >0 à des taux dâactualisation de plus en plus grand. Cette étude recommande aux gestionnaires de la machine de mettre en place un système de gestion viable et équitable par lâadoption des prix de concassage uniforme et lâélaboration dâun système de comptabilité de la concasseuse ; aux producteurs dâaccroitre lâutilisation de la machine (prototype amélioré). A lâICRAF cette étude recommande dâaméliorer la performance de concassage de la concasseuse, de faire un suivi-évaluation régulier de son utilisation, le recyclage des machinistes, de conduire dâautres essais de concassage mécanisé avec des noix très mature de longue date afin de déterminer de nouvelles performances. A lâétat dâencourager les producteurs à la plantation des arbres de njansang par les programmes de reboisement
Replication data for: Agricultural and trees products programme, baseline impact assessment survey.
No full textThis study was done to determine the baseline impact assessment survey of agricultural trees, products programme in North and West region of Cameroon. 44 households were sampled using questionnaire whereby some household characteristics were recorded. There was also a section on agricultural trees product to evaluate which type of tree are commonly exploited by farmers through vegetative propagation
Contribution to the Promotion of qualitative and quantitative production of agro forestry trees plants by the private nurseries.
No full textThe study was carried out with the overall objective to promote a qualitative and quantitative production of agro forestry trees plants by the private nurseries. The species targeted were: Dacryodes edulis, Persea americana, Mangifera indica, Prunus africana, Cola nitida, Irvingia gabonensis and Ricinodendron heudelotii. Twenty nurseries were selected in the humid forest zone and in the Western highlands (West and Northwest) of Cameroon. The perceptions of seventeen customers were evaluated regarding the quality of plants produced in these nurseries. Biophysical pa
rameters (height, diameter, number of leaves and branches, plant health ...) were measured for 315 and 205 plants selected randomly from nurseries and farmer fields respectively
Tree species screening trials in Western Kenya
No full textThe Western Kenya Integrated Ecosystem Management Project (WKIEMP) was initiated with support from the World Bank through a grant from the Global Environment Facility (GEF). The project, which became effective in July 2005, sought to improve the productivity and sustainability of land use systems in selected watersheds in the Yala and Nyando river basins through adoption of an integrated ecosystem management approach (Boye,2008; Verchot 2008). Land in lower Yala and lower Nyando areas had over the years become severely degraded because it was not appropriate for low-input subsistence agriculture and also due to lack of conservation and mitigation measures. The WKIEMPâÂÂs tree species screening trials activity therefore sought to support on- and off-farm conservation strategies and to build the capacity of local communities and other institutions in identifying and managing ecosystem issues as well as in the implementation of conservation and/or mitigation measures. Generally, the target populations often expressed preferences for exotic species like Eucalyptus spp., Casuarina equisetifolia and Grevillea robusta. While these species are highly productive, it was not clear whether these species are the best choices for degraded sites. Secondly, there was a lack of knowledge by farmers about the potential productivity of indigenous species. Farmers often remarked that indigenous tree species are not as productive as fast-growing exotics. Yet they also readily admitted that they did not have experience with these species in a plantation setting and that their observations were based on volunteer trees in the landscape that were not properly protected and cultivated. Many technical manuals suggest that indigenous species are better adapted to the local environment and should have better survival and growth rates in a region, particularly on marginal lands (Mulizane et al. 2005, Carpenter et al. 2004, Olukoye et al. 2003). Additionally, we recognized the risks associated with introduction of exotic species into new landscapes, although the preferred exotic species have shown no tendencies to be invasive. Finally, while farmers tended to believe that exotic species grow better, we have observed that there is a lot of variation in indigenous species germplasm. We believed that with proper selection the potential exists that these species could perform as well or better than exotic species on degraded sites. All of these âÂÂbeliefsâ needed to be substantiated through demonstration. Thus, ICRAF organized a series of species screening trials within the framework of the WKIEM Project. The trials were also to serve as demonstration plots to sensitize farmers to the potential of indigenous trees. The main objective of the tree species screening trials was to assess the performance of appropriate indigenous tree species relative to farmer-preferred exotic species on degraded lands. The hypotheses were: H1: Indigenous trees will have higher survival rates during the first year of planting than exotic species on degraded soils. H2: Indigenous trees will grow faster on degraded soils than exotic species. Additionally, we sought to explore the potential to develop a predictive model for
tree performance on degraded lands through a widespread network of trials that cover a large geographic area and that span a wide variation in climate, soils and other biophysical conditions
Analyse de la chaîne de valeur des produits agroforestiers: cas du Gnetum africanum dans le Bas-congo et à Kinshasa en RDCA
No full textLe Gnetum sp, communément appelé Fumbwa en RDC est l’un des légumes feuilles des forêts humides d’Afrique Centrale très apprécié. Les enquêtes réalisées en 2010 auprès de 199 acteurs dont 64 producteurs, 72 commerçants et 63 consommateurs dans le Bas-Congo et à Kinshasa ont montré que la vente de Fumbwa par les producteurs (au niveau des villages) génère 96,5 % de rentabilité en période d’abondance de la ressource et 102,5 % en période de rareté
Replication data for: Effective propagation of Diospyros crassiflora (Hiern) using twig cuttings
No full textThe African ebony (Diospyros crassiflora) is a well-sought commercial timber tree. As a result of intense harvesting pressure it ranks high on the IUCN' 1994 CITES list as endangered. Insufficient availability of seeds has limited the current efforts to propagate D. crassiflora from seedlings. Therefore, vegetative propagation through leafy stem cutting could be an alternative. The purpose of this study was to assess the effect of four rooting media, length of cuttings and auxin (seradix-2) application on the rooting ability of stem cuttings set up in a non-mist propagator. The rooting process was monitored over 14 weeks. Root development started after 9 weeks. At 14 weeks, the Seradix-2 and rooting medium significantly improved the rooting ability. Decomposed sawdust was the best substrate. The combination of the three factors didn’t significantly influence rooting of cuttings. Stem cuttings of 5 cm length survive better in non-mist propagator. The results of the study suggest that D. crassiflora is amenable to vegetative propagation by leafy stem cutting
Local communities claims on resource rights, case studies of the Littoral, Southwest and Eastern regions in Cameroon
No full textThe Forestry and Wildlife Law of 1994 has many shortcomings that render it inadequate to respond to the socio-economic and cultural needs of the local populations, environmental resilience and carbon sequestration, and therefore needs revision. It is against this background that this study has been designed to attain the following objectives. To come out with documented claims and proposals from local communities on their resource rights for the purpose of the ongoing process of reviewing the 1994 Forestry and Wildlife Law in Cameroon. More specifically, the study was expected: 1.To review existing literature on the 1994 Forestry and Wildlife Law. Emphasis here will be on texts relating to land tenure, access
rights, and cost and benefit sharing vis-à-vis local communities and the provisions of the 1994 Forestry and Wildlife Law. The review will also extend to case studies of scenario where such claims have and have not been considered. Such a comparison will provide a focus for decision-making. 2.To carry out a participatory mapping of the claims and proposals of local communities from their perception of the provisions of the 1994 Forestry and Wildlife Law after review in working groups. In this case, attention will be on the weaknesses of the law such as abuses of the law, lacuna, incomprehensive and conflictual provisions of the law that infringe on their resource and access rights, and cost and benefit sharing. 3.To spatially map out areas of horizontal and vertical conflicts using a GPS for the update of existing maps. Emphasis here will be on areas of conflicts due to interest of stakeholders and those resulting from the absence of a harmonious legal framework for government services such as forestry, environment, mining, public works, rural development and agriculture. 4.To synthesize the claims of the local population