http://197.159.135.214/jspui/handle/123456789/958 2026-04-23T15:10:59Z 2026-04-23T15:10:59Z Sanogo, Kapoury http://197.159.135.214/jspui/handle/123456789/990 2025-08-29T11:04:11Z 2016-10-08T00:00:00Z

Valitdating methods for estimating carbon sequestration and potential of Vitellaria paradoxa c.f. Gaertn. in delivering ecosystem services from parkland systems in southern Mali, West African Sanogo, Kapoury Vitellaria paradoxa is an indigenous tree species endemic to the African savannas. This species plays an important role in farmer’s mitigation and adaptation to climate change through its ecosystem services. Unfortunately, the species is declining in the Sahel including southern Mali because of its sensitiveness to recurrent drought due to climate change. Understanding the underlining processes of such decline and their consequences on the livelihoods of the rural farmers requires the development of appropriate methods and approaches. Therefore our study aimed at validating methods for estimating carbon sequestration and evaluating the potential of V. paradoxa in delivering ecosystem services for the well-being of the population in southern Mali. But before we attempted to elucidate farmers’ perception of climate change and their coping measures. Our findings revealed a range of coping measures used by farmers to adapt to climate change effects including the use of improved drought-tolerant crop varieties, diversification of crops, off-farm activities and seasonal migration. The contribution of V. paradoxa in annual gross income of rural households ranged from 4% in Koutiala (northern site) to 8% in Yanfolila (southern site). This seems to indicate an increase of the importance of this species in relation to increase rainfall and increase density of V. paradoxa going from the north to the south of Mali. Methods testing revealed that agent based could be used for V. paradoxa yield dynamics assessment in one hand and in another hand that fractal branch analysis (FBA) could be used for the above and belowground biomass and carbon estimation of this species. The aboveground carbon stock in Koutiala (2.16±0.44 Mg C ha-1) by shea trees was not significantly different from that of Yanfolila (3.21±0.60 Mg C ha-1). Similar trend was observed for the belowground carbon stocks between sites. This study indicated the risk of overestimating the biomass using generic model as all values of b were below 2.67. Furthermore, it clearly indicated that dendrochronology can be applied to study the impact of climate change on the growth of V. paradoxa. A Thesis submitted to the West African Science Service Centre on Climate Change and Adapted Land Use and the Université Félix Houphouët-Boigny, Côte d’Ivoire, in partial fulfillment of the requirements for the degree of Master of Science Degree in Climate Change and Biodiversity

2016-10-08T00:00:00Z Boakye, Emmnauel Amoah http://197.159.135.214/jspui/handle/123456789/989 2025-08-29T10:52:51Z 2016-09-29T00:00:00Z

Effect of CLimatic Variation and Agricutltural Landuse on Woody Plant Diversity and Growth of Riparian Forests in the Volta Basin of Ghana Boakye, Emmnauel Amoah Conservation measures such as creation of buffer zones are used to protect riparian forests (RF) under the Freshwater Buffer Zone Policy of Ghana. Nevertheless, scientific information on the impact of climate change and agricultural landuse management on the buffer zone is scarce. This study used Afram (HS, Humid savanna) and Tankwidi (DS, Dry savanna) riparian catchments within the Volta basin of Ghana as research sites to assess the effect of climatic variation and agricultural landuse on woody plant diversity and growth of RF. The research integrated field inventorying, remote sensing, stable carbon isotope and dendrochronological techniques for the RF assessments. Analysis of time series Landsat images showed that forests area in the Afram and Tankwidi riparian catchments have been lost at a deforestation rate of 1-4% per annum from 1986 to 2014. The effect of the spatial deforestation was confirmed by significant reduction in the richness and diversity and degrading structural characteristics of woody plants in RF from protected areas to farmlands in both catchments. These degrading conditions put the farmland riparian landscape at a greater risk of harm through climatic disturbances such as fires and flooding. When sample riparian trees (Afzelia africana [evergreen] and Anogeissus leiocarpus [deciduous]) were tested, the results as it was revealed through the analysis of growth ring width and carbon-13 isotope showed that a similar climatic forcing caused by the movement of the intercontinental convergence zone is driving the growth of riparian trees in both the HS and DS. The study further showed that A. leiocarpus has higher growth rate and resilient to water stress than A. africana. A significant correlation of the trees with the equatorial Pacific Ocean Sea Surface Temperatures revealed that the riparian forests are impacted during El Niño years which are normally responsible for drought in the West African sub-region. Because of the negative effects of agricultural landuse intensification and climate change, the study recommends the enforcement of the Freshwater buffer zone policy of Ghana in order to rescue farmland riparian buffer from further degradation. Furthermore, there is the need to reforest degraded riparian areas on farmlands. Such reforestation activities should consider A. leiocarpus owing to its high fitness and growth rate in order to speed up the recovery of the riparian forest cover. A Thesis submitted to the West African Science Service Centre on Climate Change and Adapted Land Use and the Université Félix Houphouët-Boigny, Côte d’Ivoire, in partial fulfillment of the requirements for the degree of Master of Science Degree in Climate Change and Biodiversity

2016-09-29T00:00:00Z Ceesay, Adam http://197.159.135.214/jspui/handle/123456789/988 2025-08-29T10:47:34Z 2016-10-07T00:00:00Z

Mangrove degradation and its effects on estuarine fisheries: case study of Tanbi Wetland National Park, The Gambia Ceesay, Adam Climate-induced ecosystem changes were studied in Tanbi Wetland National Park (TWNP) in conjunction with the major land use types i.e. agriculture, settlement, tourism, oyster processing, completely fragmented and partially fragmented zones. To study hydrological changes in TWNP in The Gambia, in-situ analyses of physico-chemical parameters and nutrient build-up were conducted during the peak discharge period of the River Gambia in 2013 and repeated during the peak dry season in 2014. Mangrove vegetation dynamics was assessed by remote sensing, using Landsat images of decadal time series covering 1973 – 2012. To assess seasonal changes in the fish assemblage in relation to the hydrological changes, fish were sampled at all the land use types using a seine net during the rainy and dry seasons. A questionnaire-based assessment of local knowledge on climate-induced ecosystem changes was also conducted. Average salinity in TWNP was 24.5 and 35.8 ppt for the rainy and dry seasons respectively. Mangrove vegetation cover declined by 6% while grassland increased by 56.4% from 1973-2012. 43 fish species from 25 families were recorded from 2013-2014. Fish species richness declined by 16% and abundance by 35% as the seasons changed from rainy to dry. Fish bio-ecological categories were dominated by estuarine species of marine origin (Em) (47%) throughout the year, 2014. Multidimensional Scaling (MDS) of the environmental variables indicated salinity as the main water variable influencing fish species richness in TWNP. Local awareness about the climate change concept was high (70%). However, local adaptation practices to climate-induced ecosystem changes were low (50%). Based on the low percentage loss in vegetation cover, this research concludes that except at the completely fragmented zone, the impacts of human activities on mangrove vegetation in TWNP are negligible. It also demonstrates that the decline in the fish assemblage is due to local extinctions caused by seasonal hyper-salinity. A Thesis submitted to the West African Science Service Centre on Climate Change and Adapted Land Use and the Université Félix Houphouët-Boigny, Côte d’Ivoire, in partial fulfillment of the requirements for the degree of Master of Science Degree in Climate Change and Biodiversity

2016-10-07T00:00:00Z Vanié, Linda Louyounan Paricia épouse Léabo http://197.159.135.214/jspui/handle/123456789/987 2025-08-29T10:32:34Z 2016-12-17T00:00:00Z

Ectomycorrhizal Fungi of Comoé Naitonal Park, a Biosphere Reserve in notheast Côte d’Ivoire: Diversity, Fruiting Phenology and Production in Relation to climate variability Vanié, Linda Louyounan Paricia épouse Léabo The key role of ectomycorrhizal (EcM) fungi in ecosystems functioning has been demonstrated worldwide. However, their diversity, spatial distribution, fruiting phenology and production as influenced by climatic parameters variability remain poorly understood in tropical African forests. Weekly surveys were conducted from April to early October 2014 at the Comoé National Park (CNP), Côte d’Ivoire (West Africa) in nine permanent plots established in Isoberlinia doka (IW), Uapaca togoensis (UW) and Mixed (MW) woodlands. Morpho-molecular technics were used to identify collected specimens and to reconstruct their phylogeny. Non metric multidimensional scaling (NMDS) of EcM fungi fruit bodies abundance was run with forest trees´ aggregation fitted within plots using the package VEGAN. Hierarchical clustering based on dissimilarity and indicator species analysis were run to characterize communities. Final, correlation between edible species production and climatic parameters recorded per plot were performed with functions PRCOMP and COR set at Spearman method. All analyses were computed with the statistical program R. A total of 123 EcM fungi species belonging to 23 genera and nine families collected at CNP. High Simpson index of diversity (1-D) but weak evenness were respectively 0.97 and 0.54 for IW, 0.97 and 0.61 for MW, 0.96 and 0.52 for UW. Yet, weekly-based species accumulation curves did not reach an asymptote. Stem density of Uapaca togoensis Pax and Isoberlinia doka Craib & Stapf were the most important tree parameters in EcM fungi distribution (respectively r2 = 0.92 / p-value = 0.002 and r2 = 0.83 / p-value = 0.018). Two sites groups and four species estimated good indicators were thus highlighted. 27 species were identified as edible based on literature. They started fruiting in mid-May, 02 weeks after the first important rain. Productions varied with frequency and intensity of rainfalls. The total fresh biomass production varied from 34.72 kg/ha in UW to 25.25 kg/ha in MW, whilst IW yielded 24.11 kg/ha. Productions of ten edible species were significantly correlated to all climate parameters recorded per habitat: negatively for air and soil temperature and positively for relative humidity, soil moisture and rainfall intensity. However, production of Gyroporus castaneus was negatively correlated with both soil moisture and rainfall intensity recorded in UW. A Thesis submitted to the West African Science Service Centre on Climate Change and Adapted Land Use and the Université Félix Houphouët-Boigny, Côte d’Ivoire, in partial fulfillment of the requirements for the degree of Master of Science Degree in Climate Change and Biodiversity

2016-12-17T00:00:00Z