81 research outputs found
Pre-Impoundment Fish Stock Assessment of the Black Volta: A Contribution to Fisheries Management of Bui Reservoir in Ghana
A length-based fish stock assessment of the Black Volta River in Ghana was undertaken prior to its damming at Bui in 2011. The approach involved estimation of the population parameters and exploitation rates of dominant fish stocks using TropFish R. The targeted species were: Alestes baremoze, Hydrocynus forskalii, Hemisynodontis membranaceus and Labeo coubie. The estimated asymptotic length (L∞) ranged from 30.8 – 48.2 cm standard length (SL) with derived longevity of 11 – 27 years for the assessed species. The estimated growth coefficient (K) value ranged from 0.10 – 0.25 yr-1 which suggested slow growth rates. The estimated length at first capture (Lc50) was lower than the length at first maturity (Lm50) for all the assessed fish species which suggests the presence of recruitment overfishing within the fish stocks. The total mortality rate (Z) was relatively high ranging between 0.51 and 1.34 yr-1 suggesting that the stocks were over-exploited during the pre-impoundment period. The exploitation rate (E) for the assessed fish species were lower than the maximum exploitation rate (Emax) which indicates that the species are far from collapse. These estimates are baseline scientific information for designing a Fisheries Management Plan for the Bui reservoir. Meanwhile, alternative livelihood and employment opportunities such as cage fish culture are to be explored to reduce the fishing pressure on the reservoir
Phylogenetic and microscopic studies in the genus Lactifluus (Basidiomycota, Russulales) in West Africa, including the description of four new species
Despite the crucial ecological role of lactarioid taxa (Lactifluus, Lactarius) as common ectomycorrhiza formers in tropical African seasonal forests, their current diversity is not yet adequately assessed. During the last few years, numerous lactarioid specimens have been sampled in various ecosystems from Togo (West Africa). We generated 48 ITS sequences and aligned them against lactarioid taxa from other tropical African ecozones (Guineo-Congolean evergreen forests, Zambezian miombo). A Maximum Likelihood phylogenetic tree was inferred from a dataset of 109 sequences. The phylogenetic placement of the specimens, combined with morpho-anatomical data, supported the description of four new species from Togo within the monophyletic genus Lactifluus: within subgen. Lactifluus (L. flavellus), subgen. Russulopsis (L. longibasidius and L. pectinatus), and subgen. Edules (L. melleus). This demonstrates that the current species richness of the genus is considerably higher than hitherto estimated for African species and, in addition, a need to redefine the subgenera and sections within it
POVERTY AND SUSTAINABLE SOCIO-ECONOMIC DEVELOPMENT IN AFRICA: THE NIGERIA EXPERIENCE
The paper argues that poverty has remained a major obstacle to sustainable development and democracy in the global South. With the return to civil rule in 1999 in Nigeria, hopes were high that the return to democracy will stem the decline of the economy and provide the citizenry with the social dividends of democracy. More than a decade after the economy is still on it’s kneels with more than half of the population living on less than one dollar per day. With the use of dependency theory the paper posited that unless the people are empowered to make choices and participate in making decisions that affects their lives sustainable socio-economic development will remain elusive in Africa in general and Nigeria in particular
The genus Lactarius s. str. (Basidiomycota, Russulales) in Togo (West Africa) : phylogeny and a new species described
Lactarius s. str. represents a monophyletic group of about 40 species in tropical Africa, although the delimitation of the genus from Lactifluus is still in progress. Recent molecular phylogenetic and taxonomic revisions have led to numerous changes in names of tropical species formerly referred to Lactarius. To better circumscribe the genus Lactarius in Togo, we combined morphological data with sequence analyses and phylogeny inference of rDNA ITS sequences. Morphological and molecular data were generated from specimens sampled in various native woodlands and riverside forests; Lactarioid- and Russula sequences from public GenBank NCBI, and UNITE are included for phylogenetic analysis. The Maximum likelihood phylogeny tree inferred from aligned sequences supports the phylogenetic position of the studied samples from Togo within the subgenera Piperites, and Plinthogali. Lactarius s. str. includes about 13 species described from West Africa, of which eight were not previously known from Togo, including one new species: Lactarius subbaliophaeus identifiable by the presence of winged basidiospores, a pallisadic pileipellis with a uprapellis composed of cylindrical cells, inconspicuous pleurocystidia, and fusiform or tortuous, often tapering apex marginal cells. It can also be recognised by a transparent white latex that turns pinkish and then blackish, and a bluish reaction of the flesh context with FeSO4. These features mentioned do not match any of the morpho-anatomically most similar species, notably L. baliophaeus and L. griseogalus
Strengthening forest landscape restoration through understanding land use dynamics: case study of Tchamba Prefecture (Togo)
Land use and land cover (LULC) change remains a major concern in many countries. To examine how land is used for increased actions on forest landscape restoration (FLR) issues, this study analyses LULC changes from 1991 to 2022 and predict future patterns for the years 2050 in Tchamba Prefecture, Togo, using remote sensing and the Cellular Automata-Markov modelling technique. Results show that dense forests and gallery forests (18.85%), open forest/woodland (20.17%), and tree and shrub savannah (50.04%) were the predominant classes of the landscape in 1991. However, by 2022, most tree and shrub savannah had been converted to mosaic crop/fallow land (52.27%), open forest/woodland (19.32%), and plantation (7.09%). Thus, between 1991 and 2022, forest area decreased from 89.87% to 48.96%; a 45.52% reduction in coverage. Predictions are that open forest/woodland, tree and shrub savannah will decline, while mosaic crop/fallow land will increase (51.66%). However, slight increases were recorded in plantation (9.43%) and a slight balance in dense forests/gallery forests (16.17%). Consequently, forest area will slightly change between 2022 (48.96%) and 2050 (47.41%). These changes in LULC are associated to socio-economic pressures and political instability in the 1990s. So, the return to stability, the promotion of community forests as a key restoration model, and the valorisation of agroforestry species allows for the stabilisation of dense forests/gallery forests areas and an increase in plantation. Thus, it is therefore for all stakeholders involved in restoration processes to consider this information when planning FLR activities
Public Goods, Signaling, and Norms of Conscientious Leadership
I study a sequential-move public goods game based on the notion that leadership comes with an obligation; conscientious leadership. Provision by the leader of an amount of the public good below a minimum imposes a psychological cost on the follower which increases his unit cost of contribution. The leader has private information about his type and his cost of contributing to the public good. The model combines a follower’s concern for fairness and informational signaling about conscientious leadership. I find that, under certain conditions, the follower’s equilibrium contribution is an increasing or non-monotonic function of the leader’s equilibrium contribution. The non-monotonicity result is consistent with evidence in a recent field experiment (Jack and Recalde, J. Public Econ, 2015) but cannot be obtained in previous theoretical models of voluntary public goods games that were based on only signaling information (i.e., about the quality of the public good or the return to contributions to the public good). Surprisingly, I find that, for this result to hold, the follower’s distaste for non-conscientious leadership must be sufficiently low. I also find that the leader may not act conscientiously if he does not have an informational advantage to exploit
Determinants of overweight with concurrent stunting among Ghanaian children
Abstract Background Malnutrition (undernutrition and overnutrition) is a major public health problem in Ghana –affecting growth and development of individuals and the nation. Stunting and overweight are of particular interest, as recent national surveys show a rising trend of overnutrition and stubbornly high burden of stunting among Ghanaian children. There are currently no data on the simultaneous occurrence of overweight and stunting within individuals in Ghana. This paper presents the burden, the individual-level, and contextual determinants of overweight with concurrent stunting among Ghanaian children. Methods This study analyzed data set of the fourth round of the Ghana Multiple Indicator Cluster Survey (MICS4). Bivariate analyses were used to describe selected characteristics of survey respondents and their children. Hierarchical modelling approach facilitated identification of significant distal, intermediate and proximal factors/determinants of concurrent stunting and overweight. Both crude and adjusted prevalence ratios via a multivariable Poison regression model with their corresponding 95% Confidence Intervals (CI) are reported. Variables with p ≤ 0.25 at the bivariate level were included in the multivariable analysis. An alpha value of 5% was used to indicate significance. Results Of 7550 cases (children) analyzed, the prevalence of stunting was 27.5%; underweight was 17.3%; and wasting was 7.7%. The prevalence of overweight and concurrent overweight and stunting were respectively 2.4% and 1.2%. Children who belonged to the fourth wealth quintile, were more likely to be overweight and concurrently stunted as against children belonging to the poorest quintile (aPR = 1.010; 95% CI, 1.003–1.017). Compared to religious (Christians/Muslim/Traditionalist) household heads, children whose household heads did not belong to any religion had 2 times the rates of the Overweight with concurrent stunting (PR = 2.024; 95% CI, 1.016–4.034). Children with mothers aged 20–34 and 35–49 had an increased though insignificant prevalence ratio of association (aPR = 1.001; 95% CI, 0.994–1.005) and (aPR = 1.001; 95% CI, 0.998–1.012) respectively. Conclusion This analysis determined the prevalence of concurrent stunting and overweight among Ghanaian children to be 1.2%. Four contextual variables (breastfeeding status, religion, geographic region, and wealth index quintile) were associated with overweight with concurrent stunting. We conclude that, only contextual factors are predictive of DBM among children under five living in Ghana
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