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Influence of Topography on the Distribution and Structure of Woody Plants in the Senegalese Sahel (Sandy Ferlo)

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American Journal of Plant Sciences 2024年第1期15卷 14-28页

作者： Moustapha Bassimbe Sagna Aïssatou Ndong Thiam Khoudia Niang oumar sarr Aly Diallo Sekouna Diatta Daouda Ngom Aliou Guissé Department of Plant Biology Faculty of Science and Technology Cheikh Anta Diop University Dakar Senegal IRL 3189 “Environment Health Society” Tessekere Human Environment Observatory (Senegal) Dakar Senegal Department of Agronomy and Plant Production El Hadji Ibrahima Niasse University Kaolack Senegal Department of Agroforestry Assane Seck University Ziguinchor Senegal

This study describes the floristic composition and structure of a woody stand in the Senegalese Sahel, paying particular attention to the edaphic factors of its floristic composition. A stratified inventory considering the different relief units was adopted. Woody vegetation was surveyed using a dendrometric approach. The results obtained show that the flora is dominated by a few species adapted to drought, such as Balanites aegyptiaca (L.) Del., Calotropis procera Ait. and Boscia senegalensis (Pers.). The distribution of this flora and the structure of the ligneous plants are linked to the topography. In the lowlands, the flora is more diversified and the ligneous plants reach their optimum level of development compared with the higher relief areas. In the lowlands, there are a few woody species which, in the past, were indicative of better climatic conditions. These are Anogeissus leiocarpus (DC.), Commiphora africana (A. Rich.), Feretia apodanthera Del., Loeseneriella africana (A. Smith), Mitragyna inermis (Willd.) and Sclerocarya birrea (A. Rich). It is important that their reintroduction into reforestation projects takes account of their edaphic preference.

关键词： Woody Plants Distribution Topography Ferlo Senegal

Diversity and Structure of the Woody Stand in a Sudano-Sahelian Transition Zone in Senegal

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Influence of Topography on the Distribution and Structure of Woody Plants in the Senegalese Sahel (Sandy Ferlo)

Open Journal of Ecology（生态学期刊） 2024年第1期

作者： oumar sarr Moustapha B. Sagna Amy Bakhoum Sékouna Diatta Aliou Guissé

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Management of the Water Slide Brought and Saline Flow in Irrigated Onion (Allium cepaL.) Cultivation in the Senegal River Delta

American Journal of Plant Sciences（美国植物学期刊） 2024年第1期

作者： Moustapha Bassimbe Sagna Aïssatou Ndong Thiam Khoudia Niang oumar sarr Aly Diallo Sekouna Diatta Daouda Ngom Aliou Guissé

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Agricultural Sciences 2021年第11期12卷 1255-1268页

作者： Eric Kaly oumar sarr Raymond Malou Sékouna Diatta Daouda Ngom Aliou Guisse Laboratory of Plant Ecology and Eco-Hydrology Department of Plant Biology Cheikh Anta Diop University Fann Dakar Senegal Hydrogeology Laboratory Department of Geology Cheikh Anta Diop University Fann Dakar Senegal

The find for the optimal slide of water to bring to the plot during the irrigated onion crop was important in order to limit the recharge of the water table close to the soil surface. The quantities of water supplied during onion irrigation were estimated from measurements made with a metal crest to the plot positioned at the tertiary canal. The flow rates at the tertiary canal directly irrigating the plot were recorded during irrigation. From this flow rate, the quantity of water supplied to each plot was determined. From then, the performance of the irrigated system in onion cultivation should pass on the management of this water slide at the level of the hydroagricultural facilities. The integrated soil water mass, salinity and water table dynamics monitoring system was used to assess the water requirements of onion following the irrigation. The daily water requirement of onion in the holland soil of the delta was estimated to average 0.45 g/m3. These requirements were varied according to the development stage of the crop. The water level between the ridges was between 6 and 9 mm during irrigation. This was not permanent, it infiltrated between 12 and 18 hours. This type to the stingray irrigation did not favour the arrival of the water table on the surface. The only fluctuations in the water table were observed during the bulb maturation phase. During this phase, the soil water masses were important. The electrical conductivity recorded varied during the campaign. At the beginning of irrigation, it was 3.62 mS/cm on a 30 cm profile, it decreased towards the end of the irrigations to reach 2.06 mS/cm. The quantities of salt recorded on a 30 cm profile varied from one month to the next;they were 0.468 t/ha at the beginning of irrigation (January) and 0.275 t/ha at the end of the campaign (April). From these results we can say that land degradation in the Senegal river delta would be linked to the arrival of salty groundwater on the surface.

关键词： Slide of Water Water Mass Stingray Irrigation Billon Salinity Onion

Characterization and Risk Assessment of the Collapse of the Woody Stand of Ecosystems of the Fathala Forest (Saloum Delta Biosphere Reserve-Senegal)

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American Journal of Plant Sciences 2021年第7期12卷 975-993页

作者： Eric Kaly oumar sarr Sékouna Diatta Abdoul Aziz Diouf Djibril Diouck Daouda Ngom Laboratory of Plant Ecology and Eco-hydrology Department of Plant Biology Cheikh Anta Diop University Dakar Senegal Ecological Monitoring Center for The Management of Natural Resources (CSE) Fann Residence Dakar Senegal National Parks Directorate Ministry of Environment and Sustainable Development Dakar Senegal

The objective of this study is to characterize and assess the risk of collapse of woody plant formations in the Fathala forest. In recent years, this forest has suffered a sharp reduction in its plant cover to the point of compromising the survival of populations of certain animal species such as the Red colobuses. The methods used are respectively constituted by the transect method, the dendrometric statements method and that of establishing the red list of ecosystems of the IUCN. The specific richness comprises 56 species divided into 47 genera and 22 families. The density is higher in the unfenced area (369 ind/ha in clear forest and 53 ind/ha in gallery forest) compared to the fenced area (160 ind/ha in clear forest versus 48 ind/ha in gallery forest). A study of the plant formations shows a strong degradation of the ecosystems passing from a clear and dry Sudanese forest to a wooded savannah. The cover rate in the fenced area is 20% in gallery forests and 25% in clear forests;in the unfenced area, it is 19% and 23% in gallery forests and clear forests, respectively. The application of the IUCN criteria shows an annual rate of collapse is -6 ind/ha in gallery forests and -4 ind/ha in clear forests. The annual rate of cover collapse would be -3.75% and -2.9% for gallery forests and clear forests, respectively. These results classify the forest in the Critically Endangered category. The main factors responsible for this degradation are, among others, anthropogenic actions and climatic pejoration. These results could constitute a basic tool for undertaking an improvement in the management of this forest, which is a living environment for an animal species.

关键词： Plant Formation Woody Stand Assessment Collapse of Density and Cover

Development of Allometric Models for Estimating the Biomass of Sclerocarya birrea(***) Hoscht and Boscia senegalensis(Pers.) Lam. ex Poir.

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Open Journal of Ecology 2020年第8期10卷 571-584页

作者： Ramata Talla Moustapha Bassimbé Sagna Mariama Dalanda Diallo Aly Diallo Daouda Ndiaye oumar sarr Aliou Guisse Cheikh Anta Diop University Department of Plant Biology Dakar Senegal Observatoire Homme-Milieux international de Téssékéré CNRS/Université Cheikh Anta Diop Dakar Senegal Gaston Berger University UFR of Agronomic Sciences Aquaculture and Food Technologies Saint Louis Senegal UMI 3189 “Environnement Santé Sociétés” UGB UCAD CNRS CNRST USTTB Dakar Senegal Assane Seck University Department of Agroforestry Néma Ziguinchor Senegal

The objective of this study was to develop allometric models for estimating the biomass of Sclerocarya birrea (***) Hoscht and Boscia senegalensis (Pers.) Lam. ex Poir. The inventory of these ligneous was carried out at Widou Thiengoly (North of Senegal). The sample consists of 43 individuals of Boscia senegalensis and 15 individuals of Sclerocarya birrea. The selected individuals were dendrometrically characterized before being cut, compartmentalized (trunk, branches, and twigs) and weighed entirely. Simple regression tests were performed to examine the most explanatory dendrometric parameter (x) for biomass (y) according to two types of models: the linear model (y = ax + b) and the polynomial model of degrees 2 (y = ax2 + bx + c). The criteria for selection and validity of the models are based firstly on the tests of normality, nullity, heterogeneity and autocorrelation of the residues. The results showed that the most explanatory dendrometric parameter of the biomass was the crown surface for Boscia senegalensis and the 1.30 m diameter for Sclerocarya birrea of all the tests performed, the second-order Polynomial model is the best predictor of above ground biomass for these two species. Thus, the allometric models established to predict the biomass of these two species are: y = 0.0023x2 + 0.4851x - 0.0519 for Boscia senegalensis and y = 0.35x2 + 10.35x - 12.90 for S. birrea;with very significant correlation coefficients (R2) of 0.85 and 0.94 respectively. These results can be used for a sequestered carbon assessment study and will play a role in monitoring the carbon market in Africa.

关键词： Allometric Equation Boscia senegalensis Sclerocarya birrea Ferlo Senegal

Seasonal Performance of Solar Power Plants in the Sahel Region: A Study in Senegal, West Africa

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Smart Grid and Renewable Energy 2024年第2期15卷 79-97页

作者： Serigne Abdoul Aziz Niang Mamadou Simina Drame Astou sarr Mame Diarra Toure Ahmed Gueye Seydina oumar Ndiaye Kharouna Talla FST D&#233partement de Physique Universit&#233 Cheikh Anta Diop de Dakar Dakar S&#233n&#233gal Laboratoire de Physique de l’Atmosphère et de l’Océan Siméon Fongang Université Cheikh Anta Diop Dakar Sénégal

The main objective of this study is to evaluate the seasonal performance of 20 MW solar power plants in Senegal. The analysis revealed notable seasonal variations in the performance of all stations. The most significant yields are recorded in spring, autumn and winter, with values ranging from 5 to 7.51 kWh/kWp/day for the reference yield and 4.02 to 7.58 kWh/kWp/day for the final yield. These fluctuations are associated with intense solar activity during the dry season and clear skies, indicating peak production. Conversely, minimum values are recorded during the rainy season from June to September, with a final yield of 3.86 kWh/kW/day due to dust, clouds and high temperatures. The performance ratio analysis shows seasonal dynamics throughout the year with rates ranging from 77.40% to 95.79%, reinforcing reliability and optimal utilization of installed capacity. The results of the capacity factor vary significantly, with March, April, May, and sometimes October standing out as periods of optimal performance, with 16% for Kahone, 16% for Bokhol, 18% for Malicounda and 23% for Sakal. Total losses from solar power plants show similar seasonal trends standing out for high loss levels from June to July, reaching up to 3.35 kWh/kWp/day in June. However, using solar trackers at Sakal has increased production by up to 25%, demonstrating the operational stability of this innovative technology compared with the plants fixed panel. Finally, comparing these results with international studies confirms the outstanding efficiency of Senegalese solar power plants, other installations around the world.

关键词： Performance Study Photovoltaic Power Plant Season Variations Senegal

Psychosocial Aspects of Male Infertility at the Service of Urology-Andrology of the Hospital of the Sino-Guinean Friendship

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Open Journal of Urology 2024年第7期14卷 400-406页

作者： Alimou Diallo Thierno oumar Diallo Alpha oumar Barry Ibrahima Bah Abdoulaye Bobo Diallo oumar Raphiou Bah Urology Department of the Hospital of the Sino-Guinean Friendship Faculty of Health Sciences and Technologies Gamal Abdel Nasser University of Conakry Conakry Guinea Urology Department of National Ignace Deen Hospital Faculty of Health Sciences and Technologies Gamal Abdel Nasser University of Conakry Conakry Guinea

Objective: Describe the psychosocial aspects of male infertility at the hospital of the Sino-Guinean Friendship. Patients and method: It is a prospective study of a descriptive type covering a period of 6 months. The study covered 17 patients, all received for a desire to conceive after at least one year of regular sexual intercourse without contraception. The data were collected from patient interviews using a pre-established questionnaire. Results: The average age of the patients was 32.07 years with extremes of 23 years and 42 years. During this study, 64.70% of patients were no longer participating in community ceremonies. The patients’ relationships with their spouse and family deteriorated in 52.94% and 47.06%, respectively. Conversely, relations with the family of origin remained unchanged in 70.59 percent of cases. The reduction in economic activity was by 13 patients (76.48%). Conclusion: Male infertility causes a real psychic earthquake in men with its corollaries of negative feelings. The rather complex moral repercussions of male infertility affect not only the individual, his/her partner, and family, but also economic activity.

关键词： Male Infertility Psycho-Social Aspect Psychic Earthquake

Spatial Analysis of Structural Changes and Floristic Distribution of Forest Landscapes in the Centre-West Region of Burkina Faso

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Journal of Geoscience and Environment Protection 2024年第9期12卷 246-268页

作者： Stéphane Koudougou oumar Kaboré Space and Society Dynamics Laboratory Université Joseph KI-ZERBO Ouagadougou Burkina Faso National Center for Scientific and Technological Research/Institute for Environment and Agricultural Research (CNRST/INERA) Space and Society Dynamics Laboratory of Université Joseph Ki-Zerbo Ouagadougou Burkina Faso

Land use and occupation dynamics impact landscape structure, diversity, richness and balance of vegetation cover. The aim of this study is to describe the process of fragmentation of the forest landscape from 1990 to 2020 and its effects on the degradation of the floristic characteristics of the vegetation in the Central West region of Burkina Faso. To achieve this, satellite data were collected and processed as part of a mapping approach to describing the landscape and the different types of landscape fragmentation. Mapping indices of landscape fragmentation (relative richness, change process, patch zones, Shannon diversity index) were also calculated. These indices were programmed in Idrisi Selva’s Landscape Pattern and change process analysis module. Spatio-temporal analysis revealed that in 1990, the landscape was dominated by natural vegetation formations, covering 66.33% of the territory. By 2020, these had been degraded to 44.80% by farmlands. The mapping analysis of indices also showed that the study area is characterized by four types of landscape fragmentation, including attrition, aggregation, creation and dissection. We also observed an abundant homogeneity, diversity and richness of conservation areas with legal and land tenure status. However, the structure is heterogeneous in landscapes outside protected areas and in areas under human occupation. This shows the crucial role played by conservation areas in preserving and balancing the diversity of vegetative cover in the study area.

关键词： Change Process Fragmentation Remote Sensing Landscape Burkina Faso