Tropical root crops: research strategies for the 1980s : proceedings of the First Triennial Root Crops Symposium of the International Society for Tropical Root Crops-Africa Branch, 8-12 Sept. 1980, Ibadan, Nigeria

Meeting: Root Crops Symposium, 1st, 8-12 Sept. 1980, Ibadan, NGFrench version available in IDRC Digital Library: Plantes racines tropicales: stratégies de recherches pour les années 1980 : compte rendu du Premier symposium triennal sur les plantes racines de la Société internationale pour les plantes racines tropicales - Direction Afrique, 8-12 sept. 1980, Ibadan (Nigéria

Trends in the prevalence of female genital muti-lation and its effect on delivery outcomes in the kassena-nankana district of northern Ghana

Rational: Female genital mutilation (FGM) is prevalent in northern Ghana, as the practice is seen as a passage rite to women adulthood and thus undertaken just before marriage. Objectives: We determined the changes in trend of FGM in deliveries at the Navrongo War Memo-rial hospital, and compared the outcomes and FGM status.Design: Retrospective extraction and analysis of delivery data at the hospital from 1st January 1996 to 31st December 2003. Results: Of the 5071 deliveries, about 29% (1466/5071) were associated with FGM. The high-est prevalence (95% CI) of 61.5% (50.9, 71.2) was in women aged 40 years and above, and the lowest of 14.4% (11.7, 17.0) was in women below 20 years. The all-age prevalence of FGM showed a significant decline (p-value for linear trend < 0.01) from 35.2% in 1996 to 21.1% in 2003. About 6% (89/1466) of mothers with FGM had stillbirths compared with about 3% (123/3605) of mothers without FGM. Again FGM was associated with 8.2% (120/1466) caesarean section rate compared with 6.7% (241/3605) in mothers without FGM. Mean birth weight and frequency of low birth weights were not significantly associated with FGM status. Conclusion: Although there is a high rate of FGM among mothers in the district and is associated with a higher proportion of stillbirths and caesar-ean sections, practice has shown a significant de-cline in the district in recent years due to the pre-vailing campaigns and intervention studies. There is therefore the need to sustain the ongoing inter-vention efforts

Ghana's high forests : trends, scenarios and pathways for future developments

Deforestation and forest degradation in the tropics have been receiving both scientific and political attention in recent decades due to its impacts on the environment and on human livelihoods. In Ghana, the continuous decline of forest resources and the high demand for timber have raised stakeholders concerns about the future timber production prospects in the country. The principal drivers of deforestation and forest degradation in Ghana are agricultural expansion (50%), wood harvesting (35%), population and development pressures (10%), and mining and mineral exploitation (5%). Various measures are being pursued that are targeted at addressing the drivers of deforestation and forest degradation and at increasing the forest resource base. Understanding the key driving forces behind current forest resource development trends will help to gain insights into the possible courses of action to take to improve the developments of the resources, especially where actions that are being taken today will have an impact on the forest resources for many years to come. In this thesis, I used interdisciplinary research methods to provide insights into the current status of the forest resource base in Ghana and into its likely and possible future developments. I addressed 5 research questions: (1) What are the trends and changes associated with the growing stock in the timber production areas? (2) What driving forces account for current trends and future developments of timber resources in Ghana? (3) What different scenarios can be identified and how will these affect future developments of timber resources in the high forest zone? (4) What factors motivate farmers to engage in on-farm tree planting and management? (5) To what extent do the current trends of forest resources drive forest transition in Ghana? National forest inventory data, timber harvesting data and forest plantation establishment data showed that the growing stock in both on- and off-reserve production areas have been declining since 1990. Ghana’s average forest growing stock of 40m3 per ha is much lower than the 195 m3 per ha for the Western and Central Africa sub-region. Timber harvesting records also indicate that, in recent decades, total timber harvests have mostly been substantially higher than the annual allowable cut, resulting in an increasing gap between national timber demand and supply, which drives illegal logging. Current plantation establishment efforts are not sufficient to bridge the gap between demand and supply of timber, partly due to low establishment rates and lack of appropriate management of newly established plantations. Forest governance system and resource demand are the two key driving forces that affect the current trends and future developments of forest resources in the high forest zone of Ghana. Four scenarios were developed: (1) legal forestry scenario with emphasis on improving the resource base to meet high demand; (2) forest degradation, which implies a business-as-usual scenario; (3) forest transition, with emphasis on expanding the resource base in response to environmental concerns; and (4) timber substitution scenario seeking to provide wood substitutes to conserve the resource base. Across two on-farm tree planting schemes, I found that financial benefits, educational campaigns by project teams, knowledge about current environmental issues, ownership of timber for family use and access to land, grants, farming inputs, seedlings, capacity building, and market for agricultural produce are the factors that motivated farmers to engage in on-farm tree planting and management. Currently, there is no strong force toward a forest transition through any of the five generic pathways (economic development; forest scarcity; globalization; state forest policy; and smallholder, tree-based land use intensification). This is because the existing trends of forest resources developments are either too small-scale or too ineffective. In order to accelerate a forest transition in Ghana, policy and management options should target measures that reduce current degradation of natural forests, increase the area and productivity of commercial forest plantations, promote sustainable forest management, and support and encourage forest conservation and integration of trees into farming systems.</p

Some characteristics of yellow pigmented cassava

Meeting: Root Crops Symposium, 1st, 8-12 Sept. 1980, Ibadan, NGIn IDL-271

Plantes racines tropicales: stratégies de recherches pour les années 1980 : compte rendu du Premier symposium triennal sur les plantes racines de la Société internationale pour les plantes racines tropicales - Direction Afrique, 8-12 sept. 1980, Ibadan (Nigéria)

Réunion: Symposium triennal sur les plantes-racines de la Société internationale pour les plantes-racines tropicales - Direction Afrique, 8-12 sept. 1980, Ibadan, NGVersion anglaise dans la bibliothèque: Tropical root crops: research strategies for the 1980s : proceedings of the First Triennial Root Crops Symposium of the International Society for Tropical Root Crops-Africa Branch, 8-12 Sept. 1980, Ibadan, Nigeri

Farmers’ Motivations to Plant and Manage On-Farm Trees in Ghana

Deforestation and forest degradation, especially in the agricultural landscapes, are serious threats to biodiversity conservation and sustainability of the timber industry. Planting trees on farms has been identified as having great potential to increase forest resources from agricultural landscapes. This paper examined farmers’ motivations and behaviour to engage in on-farm tree planting and management in Ghana by combining internal and external factors in a socio-psychological model. Data were collected from 156 smallholder farmers from five communities in two forest districts using a semi-structured questionnaire. Additional farm inventory data were collected from 33 farmers under two on-farm tree planting schemes. On-farm tree planting was perceived as providing income, access to personal timber for furniture, and access to loan facilities. Incentives such as provision of grants, farming inputs, capacity training, and access to markets for agricultural produce are factors that motivate on-farm tree planting in Ghana. The average standing volume of on-farm trees in the study area is 51.9 m3/ha which is almost twice the national average for the off-reserve areas in the semi-deciduous forests to which much of the study sites belong. Many farmers considered high financial costs and limited knowledge of appropriate techniques in managing planted on-farm trees as barriers to the development of tree stock on farms

Tracing forest resource development in Ghana through forest transition pathways

Tropical deforestation is a serious environmental and economic problem that has become a global issuedue to climate change and biodiversity loss. Reducing tropical deforestation is seen as national andinternational priority, given its impacts on carbon emissions, biodiversity and rural livelihoods. Somedeveloping countries have achieved a forest transition: a shift from net deforestation to net reforesta-tion, whereby a few generic pathways have been identified. Such pathways usually depend on the social,economic, ecological and political contexts of a country. A better understanding of trends related to thepathways at the country level is necessary to identify which factors drive forest transition. This paperanalyzes forest resources development trends in Ghana by focusing on forest transition pathways anddiscussing the implications for a forest transition in the country. The analysis indicates that there is cur-rently no strong force toward a forest transition through any of the generic pathways. Existing trends areeither too small-scale or too ineffective. To accelerate a forest transition in Ghana, policy and manage-ment options should target measures that reduce current degradation of closed natural forests, increasethe area and productivity of commercial forest plantations, promote sustainable forest management, andsupport and encourage forest conservation and integration of trees into farming systems

Evolutionary patterns of Toll-like receptor signaling pathway genes in the Suidae

<p>Background: The Toll-like receptor (TLR) signaling pathway constitutes an essential component of the innate immune system. Highly conserved proteins, indicative of their critical roles in host survival, characterize this pathway. Selective constraints could vary depending on the gene's position within the pathway as TLR signaling is a sequential process and that genes downstream of the TLRs may be more selectively constrained to ensure efficient immune responses given the important role of downstream genes in the signaling process. Thus, we investigated whether gene position influenced protein evolution in the TLR signaling pathway of the Suidae. The members of the Suidae examined included the European Sus scrofa (wild boar), Asian Sus scrofa (wild boar), Sus verrucosus, Sus celebensis, Sus scebifrons, Sus barbatus, Babyrousa babyrussa, Potamochoerus larvatus, Potamochoerus porcus and Phacochoerus africanus. Results: A total of 33 TLR signaling pathway genes in the Suidae were retrieved from resequencing data. The evolutionary parameter ω (dn/ds) had an overall mean of 0.1668 across genes, indicating high functional conservation within the TLR signaling pathway. A significant relationship was inferred for the network parameters gene position, number of protein-protein interactions, protein length and the evolutionary parameter dn (nonsynonymous substitutions) such that downstream genes had lower nonsynonymous substitution rates, more interactors and shorter protein length than upstream genes. Gene position was significantly correlated with the number of protein-protein interactions and protein length. Thus, the polarity in the selective constraint along the TLR signaling pathway was due to the number of molecules a protein interacted with and the protein's length. Conclusion: Results indicate that the level of selective constraints on genes within the TLR signaling pathway of the Suidae is dependent on the gene's position and network parameters. In particular, downstream genes evolve more slowly as a result of being highly connected and having shorter protein lengths. These findings highlight the critical role of gene network parameters in gene evolution.</p