Savannah Tree Research Articles

Utilization Potentials of Endangered Savannah Tree Species in North-West Nigeria

This study evaluated the utilization potentials of some endangered savannah tree species in north-west Nigeria. A multistage sampling procedure was employed. Three Local Government areas were selected, from which 36 villages were selected. A structured questionnaire was administered to 360 respondents and ten respondents were randomly selected in each village. Data obtained were analyzed with descriptive statistics. Descriptive statistics were used to assess the collected data. Most (38%) were in the 30- to 39-year-old age range. The majority sex was 100% male, 75% were married and had a family size of at least one to ten people per home. 69% of the respondents have completed formal schooling. (65%) were primarily farmers and (49%) had inherited land. Sixty-five percent of the farms were smaller than one hectare. (40%) had been farmers for an average of 21–31 years. Most farmers (100%) utilized trees as boundary demarcation, 98% as shade and 93% as medicine and wind control. However, 99% utilized trees for medicine. The predominant tree families include Fabaceae, Combretaceae, Rubiaceae, Euphorbiaceae and Caeselpiniaceae. The most familiar tree species were Azadirachta indica, Adansonia digitata, Parkia biglobosa, Lawsonia inermis, Mangifera indica, Vitellaria paradoxa, Tamarindus indica, Jatropha carcus, Diospyros mespiliformis and Acacia nilotica used to treat and cure various ailments and diseases for optimum benefits.

Assessment of the CO2 sequestration and emission potential of the Kari classified forest, Burkina Faso

ABSTRACT The aim of this study was to assess changes in the CO2 sequestration and emission capacities of the Kari classified forest. To this end, a study of land use dynamics was carried out using Landsat images from 2000, 2010 and 2019. To assess wood potential and CO2 emissions, a forest inventory was carried out by sampling. The data on vegetation dynamics and wood potential show that more than 90% of the vegetation in this forest has remained stable from 2000 to 2019. However, significant degradation of the vegetation has been recorded in shrub savannahs, tree savannahs and gallery forests. The assessment of wood potential indicates that the forest is stable, balanced and in full recovery. The forest constitutes a carbon dioxide reservoir, with approximately 2.35 MtCO2eq sequestered in 2019. The assessment also reveals that the degradation of the vegetation has led to significant CO2 emissions. Between 2000 and 2010, the study area emitted an average of 94,566 tCO2eq, i.e., an average annual emission of 9,456.6 tCO2eq. The results of this study confirm that the conservation actions carried out by the various stakeholders are making an effective contribution to protecting nature and the services it provides.

Brazilian savannah tree as bio-inspiration for hydraulic transient control in a penstock of a small hydropower plant

This study proposes an innovation, which is to use a non-circular and bio-inspired forced conduit (a new penstock with a cross section inspired by a tree trunk), to control the effects of hydraulic transients in Brazilian small hydropower plants (SHPs). The aim is to demonstrate that natural structures, adapted to periodic environmental disturbances, are better at hydraulic transient control than traditional conduits. The proposed methodology includes the following steps: (1) problem identification; (2) potential biological model identification; (3) development of alternatives; (4) implementation and testing; and (5) solution selection. This research was conducted at the São Tadeu I SHP, in the city of Santo Antônio de Leverger/MT, Brazil. The following tree biological models from the Brazilian savannah (Cerrado) were used: Handroanthus capitatus and Strychnos pseudoquina. The proposed innovation improves the conduit of the traditional circular section and the relief valve solution of the criteria studied. The reason for this improvement was the reduction of wave speed in the non-circular section (from 1126 to 583 m s−1).

Environmental forensics evaluation of residual soybean sludge using trees of Brazilian savannah

Truck and train are the primary transport means for soybean shipments to national or international markets from Brazil. Substantial amounts of grain residues are dispersed throughout the transport and may accumulate in various places by the runoff. The objective of this study was to evaluate the contamination and mortality of Brazilian savannah trees due to the accumulation of soybean runoff that comes from a grain storage yard. Xylem samples were collected from 28 dead trees in a forest where residues severely polluted the natural environment. Increment cores at breast height were also taken from 25 living trees for control procedure. All samples were analyzed by X-ray densitometry and microfluorescence (XRF) techniques. No differences were observed in the xylem densitometry profile from bark to pith between dead and living trees, indicating that the stagnation in cell production and tree growth occurred drastically after the accumulation of soybean residual sludge, which was confirmed by temporal analysis of satellite images. Significantly higher S, P, Ca and Fe concentrations were observed close to the bark in dead trees. The roots of dead trees accumulated higher amounts of Al, Si, S, Ca and Mn. Higher K, Ca and Si concentrations and lower Mn concentrations were observed in trees closer to the polluted area, and it indicates the need for soil remediation. However, As, Pb and Cd, markers of fertilizers and pesticides in soybean production, were not detected by the analyses performed. It is likely that the residual soybean sludge and its fermentation process during the rainy season (tree - growing season) have generated toxic concentrations of inorganic constituents, that together with warmer soil conditions caused the death of many trees. This study provides tools for the assessment of the environmental impact of soybean production through a novel protocol for monitoring the physical and chemical patterns of tree growth using rapid microscopic scale X-ray techniques.

Effect of Simulated Drought and Rainfall Fluctuation on Seedling Growth of Two Savannah Trees Species in Sudan: An Experimental Exploration

Climate change scenarios project that several regions, especially in dryland areas of sub-Saharan Africa, will undergo increasing aridity and, subsequently, expanding land degradation. The study aims to investigate the effect of two drying treatments on establishing and growing Hashab (Acacia senegal) and Boabab (Adansonia digitata) in nursery conditions. Through a 2×2 factorial experiment, seedlings grown in a mixture of silt and sand soil (2:3) were treated by irrigation intervals of one or two liters every three days for 14 weeks to simulate rainfall fluctuation patterns. Seedling germination rate, leaf number, stem height, and diameter were measured weekly; taproot length, shoot, and root dry weights were also assessed. The results showed that neither drying treatment significantly affected A. senegal and A. digitata seedling growth parameters. However, an interaction effect was found in the height and diameter for A. senegal and shoot dry weight for A. digitata. The study concluded that A. senegal and A. digitata seem tolerant to drying treatment. Therefore, the two species are recommended for afforestation programs in areas with relatively harsher conditions. Also, exposing the seedlings of these studied species to similar, extended periods of simulated drought (e.g., 6 – 12 months) is recommended for future studies.

Land use and land cover change detection and prediction based on CA-Markov chain in the savannah ecological zone of Ghana

Environmental problems have accompanied the accelerated land use and land cover change (LULCC), yet few local level studies make an attempt to assess the dynamics of LULCC. This work employed GIS and remote sensing to quantify the past and predict future dynamics of LULCC based on the synergy Cellular Automata (CA) - Markov Chain Model (MCM). The results revealed that agricultural land in the Bongo district witnessed the greatest expansion from 10.03% to 27.17% of total area from 1990 to 2019, while wooded savannah area witnessed the greatest decline from a share of 42.26% to 15.51% of total area from 1990 to 2019. In the Kassena-Nankana West (KNW) district, shrub and tree savannah and agricultural land expanded from 32.91% to 54.2% and 9.44% to 18.16% of the total area, respectively, at the expense of wooded savannah area (-32.9% of total area) between 1990 and 2019. Future predictions based on prevailing socio-economic development demonstrate that the observed trend would continue till the 2050 period. In the Bongo district, the settlement area will witness the highest proportion of net increase in total area (5.63 km2) at the expense of wooded savannah (-11.26 km2) between 2019 and 2050. Conversely, in the KNW district, the shrub and tree savannah area will experience the highest proportion of net gain in total area (156.02 km2) at the expense of wooded savannah area (-111.49 km2) between 2019 and 2050. This result is an indication that the synergy CA-MCM have effectively captured the spatiotemporal trend in LULCC in this study.

Spatio-temporal Dynamics of Land use in Lake Ecosystems in the Sudano-Guinean Zone (Adamaoua-Cameroon)

The present study aims to characterize over 31 years between 1990 and 2021 the spatio-temporal mutations experienced by four lake ecosystems in the Sudano-Guinean zone of Cameroon due to strong anthropic activities caused by the increase of the demography. Landsat satellite images from 1990, 2006 and 2021 were exploited using remote sensing and GIS. The unsupervised classification was used to obtain nine land cover and land use classes (agricultural space, forest gallery, tree savannah, shrub savannah, grassy savannah, bare soil, water surface, hydromorphic zone and housing zone). The dynamics are progressive for the agricultural space (24.40 ha at Lake Bini, 24.38 ha at Lake Dang, and 16.72 ha at Lake Mballang). On the other hand, The dynamics of the plant formations is essentially regressive for the shrubby savannahs (16.21 ha at Lake Bini, 30.56 ha at Lake Dang, 118.13 at Lake Mballang and - 9.67 ha at Lake Ngaoundaba). The water surface area decreased in the lake ecosystems of Bini (0.27 ha) and Mballang (0.04). In contrast, there was an increase in the lake ecosystems of Lake Dang (0.40 ha) and Ngaoundaba (0.21 ha). The factors of this degradation are mainly human (agriculture, overgrazing and galloping demography) and result in the fragmentation of natural habitats to the benefit of cultivated areas and purely anthropogenic housing zones. The consequences likely to result from this degradation call on the inhabitants and decision-makers to reduce human activities harmful to the environment and to restore these ecosystems.

NATURAL REGENERATION CAPACITY OF VITELLARIA PARADOXA (SHEA TREE) ON THE HILLS OF BASSAR (NORTH-TOGO)

As the consequence of anthropic pressure along with climatic factors, the vegetation of the hills of Bassar is degrading day after day and a regression of many woody species is observed. Vitellaria paradoxa is a highly valued multi-use species, but it is threatened with extinction in the area. The "bell" and "L" shapes of the diameter class distribution histograms reflect aging and/or disturbed populations. Stand disturbance is illustrated by the low proportion of large diameter class individuals. The "L" shape reveals an advanced state of degradation characterized by a near absence of large diameter trees. The study of the natural regeneration of Vitellaria paradoxa on the hills of Bassar shows that the density of regeneration by seedlings, shoots and suckers depend on the diameter of the individual stem. The larger the diameter increases, the higher the density of seedlings becomes. However, plantlets stemming from seedlings are higher, and weaker from suckers and shoots. The density of Vitellaria paradoxa seedlings is lower in shrub savannahs than in tree savannahs. The analysis of variance showed that whether under the crown or outside the crown, there was a significant difference between individuals from regeneration in all the formations studied. In the inventory plots, the densities of young trees are equally variable under the crown and outside the crown as those of large trees.

Physiological responses to low CO2 over prolonged drought as primers for forest-grassland transitions.

Savannahs dominated by grasses with scattered C3 trees expanded between 24 and 9 million years ago in low latitudes at the expense of forests. Fire, herbivory, drought and the susceptibility of trees to declining atmospheric CO2 concentrations ([CO2]a) are proposed as key drivers of this transition. The role of disturbance is well studied, but physiological arguments are mostly derived from models and palaeorecords, without direct experimental evidence. In replicated comparative experimental trials, we examined the physiological effects of [CO2]a and prolonged drought in a broadleaf forest tree, a savannah tree and a savannah C4 grass. We show that the forest tree was more disadvantaged than either the savannah tree or the C4 grass by the low [CO2]a and increasing aridity. Our experiments provide insights into the role of the intrinsic physiological susceptibility of trees in priming the disturbance-driven transition from forest to savannah in the conditions of the early Miocene.

Impact of Agricultural Practices on Vegetation Structure and Carbon Sequestration in the North Region Cameroon: The Case of the Lagdo District

In order to preserve the For a good and sustainable management of vegetation in the Lagdo subdivision of the Benue division in North region Cameroon with respect to agricultural practices and the effects of climate change, a study on the impact of agricultural practices was conducted in six plant formations and three riparian villages. This study therefore assessed the impact of agricultural practices on vegetation with a focus on the assessment of plant population structure and quantification of sequestered carbon stock. Floristic surveys in six vegetation formations (forest galleries, shrub savannahs, tree savannahs, 2015/2016 crop fields, fallows of two (02) years and more than two (02) years on 50 m x 50 m plots were conducted. Floristic richness analysis identified 50 species across the surveyed sites, which were divided into 40 genera and 23 families. The most represented families in the sites are Caesalpiniaceae, Euphorbiaceae, Combretaceae, Mimosaceae and Rubiaceae, which have 5, 4, 4, 4 and 3 genera respectively. The Shannon diversity index is highest in forest galleries (3.32), in wooded savannahs (3.04); medium in fallows of more than 2 years (2.33), 2-year fallows (2.21) and shrub savannahs (2.20) and lowest in crop fields. Regarding carbon sequestration, forest galleries have carbon stocks of 57.47 tC/ha, followed by shrub savannahs with stocks of 12.66 tC/ha and fallows of more than 2 years with 3.64 tC/ha. The crop fields (0.12 tC/ha) present the lowest values, however lower than those sequestered by shrub savannahs (1.03 tC/ha) and 2-year fallows (0.88 tC/ha). The results of the study on agricultural practices in the Lagdo subdivision therefore confirm the need for sustainable management of natural resources to combat climate change.

Analysis of Phytocomponents in the n-Hexane Extract from the Stem Bark of Parinari polyandra (Benth) using FTIR and GC-MS

Parinari polyandra belongs to the family chrysobalanaceae which is made up of 115 genera and with about 3200 species distributed all over the world. Parinari polyandra also known as Maranthes is a savannah tree with very conspicuous whitish or pinkish flowers in dense and flattened panicles at the end of the branches. Parinari polyandra is about 8m high with a gnarled and twisted bore. Leaves are 6-13cm long by 3-8cm broad; usually round at both ends and sometimes with a very short pointed tip, leathery dark green and glossy on its top. This present study is aimed at investigating the phytochemicals present in n-hexane extract of the stem bark using FTIR and GCMS spectroscopy. The phytochemical analysis reveals the presence of alkaloids, cardiac glycosides, flavonoids, terpenoid, steroids, tannins and saponins. The Fourier transform infrared (FT-IR) result reveals the presence of aldehydes, ketones, alcohols, amines, phenols, alkenes, anhydride, aliphatic and aromatic compounds. The Gas Chromatography- Mass spectrometry (GC-MS) chromatogram indicated that the n-hexane extracts contain 20 compounds as indicated that could be associated with their pharmacological properties. This study justifies the ethno medicinal uses of the plants stem bark for the treatment of various ailment due to the presence of some phytochemical constituents that found uses in pharmacology.

Climate change will disproportionally affect the most genetically diverse lineages of a widespread African tree species

Global climate change is proceeding at an alarming rate with major ecological and genetic consequences for biodiversity, particularly in drylands. The response of species to climate change may differ between intraspecific genetic groups, with major implications for conservation. We used molecular data from 10 nuclear and two chloroplast genomes to identify phylogeographic groups within 746 individuals from 29 populations of Senegalia senegal, a savannah tree species in sub-Saharan Africa. Three phylogroups are identified corresponding to Sudano-Sahelian, Zambezian and Southern African biogeographic regions in West, East and Southern Africa. Genetic diversity was highest in Southern and Zambesian and lowest in the Sudano-Sahelian phylogroups. Using species distribution modeling, we infer highly divergent future distributions of the phylogroups under three climate change scenarios. Climate change will lead to severe reductions of distribution area of the genetically diverse Zambezian (− 41–− 54%) and Southern (− 63–− 82%) phylogroups, but to an increase for the genetically depauperate Sudano-Sahelian (+ 7– + 26%) phylogroups. This study improves our understanding of the impact of climate change on the future distribution of this species. This knowledge is particularly useful for biodiversity management as the conservation of genetic resources needs to be considered in complementary strategies of in-situ conservation and assisted migration.

The role of traditional leadership in local government. A research report submitted to the Faculty of Commerce, Law and Management, University of Witwatersrand. 2. Daneel, M.L. (1996). Environmental reform: A new venture of Zimba

The present work was initiated in order to evaluate the composition, structure and diversity of the flora of the Manda National Park (MNP) to contribute to its sustainable management. The survey area is a square plot of 1m x 1m and a semi plot of 10m x 10m respectively for grassy savannah and shrub savannah and a rectangular plot of 50m x 20m for woodland and tree savannah. The diameter at breast height and total height of all woody individuals were measured. The floristic inventory resulted in a total of 12885 individuals belonging to 102 species, 81 genera and 34 families. The tree savannah (78 species, 59 genera and 26 families) and woodland (65 species, 54 genera and 24 families) are richer in taxonomic groups than the shrub savannah (38 species, 32 genera and 16 families) and the grassy savannah (19 species, 18 genera and 8 families) The average density of the park and its Shannon index are respectively 1956 ind/ha and 2.82 bits. For these plant formations, their density and Shannon index are highest in the tree savannah (3507 ind/ha and 3.11 bits) and lowest in the shrub savannah (1133 ind/ha and 2.03 bits). The Piélou index for each of the plant formations is low (0.19 to 0.25), indicating a poor equi- distribution of individuals between the different species for the plant formations. In the woodland, the diametrical and vertical distributions are bell-shaped and skewed to the right, centered on young individuals. In contrast, in the Tree and Shrub Savannahs the distributions are in the shape of an inverted "J", characteristic of a formation dominated by juvenile individuals. These results lead to the conclusion that the Manda Park has a good species diversity and is under anthropic pressure due to the destruction of its vegetation cover.

Phytodiversity and Vulnerability of Protected Areas in Burkina Faso: Case of Péni Classified Forest

Protected areas contain most of Burkina Faso’s plant biodiversity which confer different benefits for the communities. However, the composition of some of them remains unknown. In a context of overexploitation and climate change, it is important to have a detailed knowledge of the vegetation of forests that have not been studied, such as Péni Classified Forest (PCF) to develop better preservation protocols. The aim of this study is to contribute to the knowledge of the flora of Burkina Faso. Phytosociological surveys were carried out in 213 plots, have identified 475 species distributed in 321 genera and 87 families. We identified during this study 201 woody species representing 38% of the woody flora of Burkina Faso. 64% of this flora is confined to shrub savannahs and 61% to tree savannahs. Among the vegetation units, shrub savannahs and tree savannahs have respectively 56.21% and 44.67% of very rare species. Poaceae (11.90%), Fabaceae-Faboideae (11.27%) and Rubiaceae (6.26%) are the most dominant families. The dominant biological types of the flora are phanerophytes (42.32%) and therophytes (30.32%), and Sudanian species (20.63%) are the best represented. Logging is the most frequent disturbance factor (100%) in the PCF. The PCF is a particular ecosystem with a great diversity but subject to many disturbances. Actions to strengthen its protection are necessary.

Monitoring Forest Recovery in Protected Forests of Northern Côte d’Ivoire Using Landsat Imagery and Intensity Change Analysis

In this paper, the initiatives of reforestation of the national forests of the North of the Côte d’Ivoire were examined using geomatics and the analysis of change of intensity by taking the case of the protected Forest of Badénou (PFB). A spatial analysis based on multi-spectral and multi-temporal Landsat imagery was carried out to assess land cover changes in the (PFB) over the past two decades and determine whether patterns of change in terms of the intensity of gains/losses of each of the land cover classes were active or dormant between the period before (2000-2013) and after (2013-2019) the reforestation initiative. Five main classes were identified: forest (dry deciduous and gallery forests), tree savannah, shrub/grassy savannah (including agricultural lands), bare lands (bare soils and degraded land areas), and water course. All classes were satisfactorily classified, with an excellent producer’s and user’s and overall accuracies and very good Kappa coefficients. The results showed that between 2000 and 2019, the forest cover in the PFB increased from 7778 ha to 5054 ha, a decrease was marked between 2000 and 2013 of approximately 60% compared to its size in 2000, while a slight increase between 2013 and 2019 (4645 ha to 5054 ha) i.e. around 9%) certainly due to the reforestation since 2016. As for the annual intensities of change for each class in both study periods, changes (gain or loss) in forest and tree savanna were relatively dormant after reforestation, while annual bare land gain was relatively active and marked, indicating that degradation of forests remains a threat to the sustainability of the PFB. Forest degradation has occurred mainly in the eastern parts of the PFB, while the central parts have regained more tree cover. These results can help identify conservation and restoration priorities and improve the overall management of the PFB.

The Influence of Periodic Fires on the High Guinean Savannas and the Carbon Stock in Cameroun

The influence of periodic fires in the high Guinean savannas of Cameroon on woody plants and carbon stock is poorly documented. To fill this gap, work was carried out in the high Guinean savannas of Cameroon with the aim of contributing to the assessment of the effects of periodic fires on the woody cover and the carbon stock. The methodology used consists of carrying out semi-structured household surveys and floristic inventories in the Arrondissement of Ngaoundéré III and Ngan’ha, in the Department of Vina. A total of 50 households were interviewed at a rate of 25 per Borough according to a questionnaire prepared beforehand. For the botanical inventories, 02 types of savannah were selected: regularly burnt savannas (shrub savannas, wooded savannas) and those not burned for at least 10 years (shrub savannas, tree savannas). The choice of control savannas was made according to the indications of the peasants. In each of them, the 1km x 20m transects were covered and the diameter at breast height (dbh) of the woody plants was measured using a dbh meter at 1.3 m from the ground for large trees. and at 30 or 50 cm from the ground for shrubs and shrubs. The results show that climate change is palpable in the area. The rains are increasingly rare, the drought has become severe and the agricultural calendar is no longer respected. The specific diversity has become relatively low with 51 species having been inventoried, divided into 46 genera and 23 families. Savannahs that are not burnt produce more biomass than those that are burnt. The perfect illustration is given by the non-burnt tree savannah of Ngaoundere III with an above-ground and root biomass of 102.23 t/ha and 20.70 t/ha respectively. <i>Annona senegalensis</i> (1.27 tC/ha) is the species contributing massively to carbon sequestration in the high savannas of the Vina. Thus, by acting on the availability of plant biomass, fires contribute to the erosion of biodiversity. Adequate measures are urgently needed to limit bushfires.

Comparative suitability of ordinary kriging and Inverse Distance Weighted interpolation for indicating intactness gradients on threatened savannah woodland and forest stands

Mapping spatial variations in tree density and woody species diversity, as indicators of intactness of tropical forests and woodlands, is potentially useful to nature conservation managers. This paper examines the comparative suitability of ordinary kriging and Inverse Distance Weighted (IDW) interpolation for mapping these variables. Two study sites representing the dense tree cover of tropical forest and the scattered tree cover in savannah woodland were used. As an interpolation variable, savannah tree density presents the challenge that tree cover is characteristically patchy. Field sampling at unevenly distributed sampling sites yielded spatial gradients in tree and shrub density and number of woody species per hectare, in relation to human harvesting. Autocorrelation indicated suitability of the data for kriging. Based on least error cross-validation statistics, the exponential semivariogram model was the most suitable for the data. Low neighborhood search radius values were more appropriate for IDW interpolation. The accuracy of the resulting tree density interpolations was judged against Normalized Difference Vegetation Index (NDVI) values from near-concurrent SPOT images. For the woodland, IDW interpolation had higher correlation with the NDVI (r = 0.782, P < 0.05) than ordinary kriging (r = 0.731, P < 0.05). For the forest, ordinary kriging had higher correlation (r = 0.921, P < 0.01) than IDW interplation (r = 0.875, P < 0.01). The results indicated that ordinary kriging is suitable for mapping tree density in dense forests, while IDW interpolation is more appropriate for scattered tree savannah woodland. The ideal interpolation technique can inform environmental management interventions.

The influence of periodic fires on the high Guinean savannas and the carbon stock in Cameroon

The influence of periodic fires in the high Guinean savannas of Cameroon on woody plants and carbon stock is poorly documented. To fill this gap, work was carried out in the high Guinean savannas of Cameroon with the aim of contributing to the assessment of the effects of periodic fires on the woody cover and the carbon stock. The methodology used consists of carrying out semi-structured household surveys and floristic inventories in the Arrondissement of Ngaoundéré III and Ngan’ha, in the Department of Vina. A total of 50 households were interviewed at a rate of 25 per Borough according to a questionnaire prepared beforehand. For the botanical inventories, 02 types of savannah were selected: regularly burnt savannas (shrub savannas, wooded savannas) and those not burned for at least 10 years (shrub savannas, tree savannas). The choice of control savannas was made according to the indications of the peasants. In each of them, the 1km x 20m transects were covered and the diameter at breast height (dbh) of the woody plants was measured using a dbh meter at 1.3 m from the ground for large trees. and at 30 or 50 cm from the ground for shrubs and shrubs. The results show that climate change is palpable in the area. The rains are increasingly rare, the drought has become severe and the agricultural calendar is no longer respected. The specific diversity has become relatively low with 51 species having been inventoried, divided into 46 genera and 23 families. Savannahs that are not burnt produce more biomass than those that are burnt. The perfect illustration is given by the non-burnt tree savannah of Ngaoundere III with an above-ground and root biomass of 102.23 t / ha and 20.70 t / ha respectively. Annona senegalensis (1.27 tC / ha) is the species contributing massively to carbon sequestration in the high savannas of the Vina. Thus, by acting on the availability of plant biomass, fires contribute to the erosion of biodiversity. Adequate measures are urgently needed to limit bushfires.

IMPACT OF GOLD MINING ON FLORA: THE CASE OF THE SISSENGUE GOLD MINE (NORTHERN COTE DIVOIRE)

This study was initiated to contribute to the sustainable management of biodiversity in mining sites in Cote dIvoire. Its objective is to determine the impacts of gold mining activities on the flora of the Sissengue gold mine located in the department of Tengrela in northern Cote dIvoire. The flora inventory was conducted along a 500 m transect combined with the surface survey and roving inventory methods. The surface survey method consisted of delimiting a 25 m x 25 m (400 m2) plot at the end of each transect. In total, nine (09) types of land use were identified in the site, namely annual crops, perennial crops, open forests, forest galleries, tree savannahs, shrub savannahs, burned areas, lakes or water reservoirs, and locality. The floristic inventories carried out in seven (07) types of land occupations allowed the identification of 207 plant species distributed among 155 genera and 61 families. In addition, thirteen (13) species with special ecological status and seven (07) species included in the IUCN red list, four of which are vulnerable. However, the floristic diversity is low in all plant formations with an average of 1.91. The shrubby savannahs record the highest densities with 1705 stems/ha while the forest galleries and open forests record the highest values of basal area, with respectively 37.2 m2/ha and 28.1 m2/ha. These vegetation formations are disturbed by the mines gold mining activities. Efforts to conserve areas dedicated to biodiversity conservation must be a priority for mining sites in Cote dIvoire.

Phytochemical Analysis and Antifungal Activity of Ficus Sycomorus L. (Moraceae) Extracts on some Dermatophytic Fungi

Ficus sycomorus L is a large, semi-deciduous spreading savannah tree that belongs to the family (Moraceae) is used by many tribes in the treatments of skin infections. The aim of this study was to carry out phytochemical analysis and antifungal evaluation of F. sycomorus L. stem and leaf Methanol extract on some dermatophytic fungi. The stem and leaf crude extracts were obtained after drying using maceration and percolation with methanol as the solvent. The extract was subjected to qualitative phytochemical screening as well as GC-MS analysis for the presence of bioactive constituents. The antifungal inhibitory effect of the crude stem and leaf extracts was assessed by agar well diffusion methods. The phytochemical screening revealed that the leaves and stem-bark contained secondary metabolites such as tannins, flavonoids, alkaloids, saponins, reducing sugar and steroid. The GC-MS assay showed that the most prevailing compound in the methanolic stem-bark extract was 2, 9, Diazabicyclo (4, 4, 0) decane-3,10 dione, while in the methanolic leaves extract was acetic acid. The anti-dermatophytic assay of the extracts against Microsporum canis and Tricophyton tonsurans showed that the extracts inhibited the fungi with zones of inhibitions ranging from 6.33±0.47 to 24.33±0.47mm with the leaf extract exhibiting higher inhibition zones than the stem extract (p˂0.01). The study shows that both the stem and leaf methanol extract of Ficus sycomorus L possesses antifungal activity and should be considered as a potential antifungal agent in search of newer agents to address dermatophytic fungal infections