The Niger River, threatened by human activities, is the main drinking water source for the popula... more The Niger River, threatened by human activities, is the main drinking water source for the population of Bamako city. This study assesses the trend of Niger River pollution in Bamako using the Water Quality Index (WQI). Fourteen parameters, namely Turbidity, Potential of Hydrogen (pH), Electrical Conductivity, Dissolved Oxygen, Total Dissolved Solids, Biochemical Oxygen Demand (BOD5), Chemical Oxygen Demand (COD), Nitrate, Nitrite, Ammonium, Phosphate, Sulphate, Chloride and Copper, were employed to characterise the Niger River water quality during the period from 2016 to 2020. Parameters were measured at 15 sampling locations. High values of Turbidity, pH and high concentrations of BOD5, COD, Nitrite, Ammonium and Phosphates were recorded. The results showed that the Niger River water quality was good for 4 months and poor for 5 months during the dry season in a low flow period. Moreover, the water quality was poor during the 3 months of the wet season in the high flow period. The ...
The semi-arid regions of the Earth are particularly vulnerable to wind erosion. The Sahelian regi... more The semi-arid regions of the Earth are particularly vulnerable to wind erosion. The Sahelian region experienced contrasted climatic conditions during the last decades, with severe drought in the 70's and 80's and a relative re-greening in the recent years. Over the same period, changes in land use have occurred with an increase of the cultivated surfaces leading to a decrease of fallows and rangelands. As a result, a significant proportion of the land is bare or sparsely vegetated, and thus is not efficiently protected from the erosive action of wind. In this region, wind erosion tends to decrease the productive capacity of the soils whose fertility is already very low. In addition, the impact of wind erosion is expected to increase significantly in the near future (1) in relation with the expected changes in climate (in particular the modifications of precipitation and surface wind) and (2) in response to the increasing land use due to population increase and the related fo...
Journal of Resources Development and Management, 2020
Highlighting the practice of water conservation (PWC) is a safe way to accomplish water savings. ... more Highlighting the practice of water conservation (PWC) is a safe way to accomplish water savings. Nevertheless, parameters affecting behavior change linked to water use keep uncertain. In this study, 467 residents (female: 272; male: 195) from three villages situated in the commune of Pelengana in Segou, Mali were investigated in order to analyze the effects of awareness, perceptions and individual water-use patterns control on PWC, and also the influence of gender on inhabitants' PWC. One-way analysis of variance (ANOVA) followed by post-hoc LSD tests were used in analyzing different data. Participants were very familiar with PWC, but stated low involvement in PWC, especially among men consumers. Although women adopted more PWC than men, the amount of water consumed by these women was more twice greater that of men. Women consumers engaged in PWC principally to reduce water costs, while men consumers applied PWC principally for water scarcity reduction. Daily habits changes and demands of extra time and effort were the principal obstacles for PWC, notably for men consumers. In all, there is a pressing need to enhance information clarity and communication among gender, consumers, and decision-makers to strengthen social assistance for water conservation.
Wind erosion flux and dune front dynamic in Manga, SE Niger Anthropic and climate changes reduced... more Wind erosion flux and dune front dynamic in Manga, SE Niger Anthropic and climate changes reduced the vegetation cover and induced dunes movement in South-east of Niger. This work aimed to characterize wind erosion on moving dunes of the Manga in Niger. Specially, it aimed to measure wind erosion flux and to determine the velocity of the dunes fronts dynamics and the optimal period of their movement. Thus, an automatic meteorological station is installed in the village of Kilakina to direction and velocity of wind and rainfall. Metallic pickets have been installed in front of 22 dunes to measure theirs dynamics. And 3 masts of BSNE sand catcher have been installed to characterize wind erosion horizontal flux. The results show that wind erosion flux is maximal at the beginning of the rainy season while wind speeds are high. Dunes front without fixation device are more mobile. On their surfaces wind erosion happened all the year because of wind speed is regularly superior to the thres...
L'envasement des cours d'eau est une des graves consequences des changements climatiques ... more L'envasement des cours d'eau est une des graves consequences des changements climatiques et des fortes pressions anthropiques au Sahel. Des taux de comblement de l'ordre de 2 a 3 cm/an ont ete mis en evidence dans ceux de la region de Niamey (Sud-Ouest Niger). Dans ce contexte, ce travail est fait pour determiner les impacts des variations piezometrique et pluviometrique sur la dynamique des matieres en suspension (MES) participant au comblement des lacs (Bangou Kirey et Bangou Bi). Les resultats obtenus montrent que Bangou Kirey, alimente par des koris drainant un plus vaste bassin versant, contient au moins 30 fois plus de MES que Bangou Bi. La concentration en MES dans Bangou Kirey a, cependant, ete impactee par l'effet de la remonte de la nappe phreatique et les apports en sediments fins apportes par les eaux de ruissellement. Elle a, en effet, ete diluee par la remonte en surface de ladite nappe. Par ailleurs, si l'influence des pluies, plus importantes et p...
Context Wind erosion plays a major role in land degradation in semi-arid areas, especially in the... more Context Wind erosion plays a major role in land degradation in semi-arid areas, especially in the Sahel. There, wind erosion is as sensitive to land use and land management as to climate factors. Future land use intensification may increase wind erosion and induce regional land degradation. Objective We aimed to estimate wind erosion responses to changing land management in a Sahelian region. Methods We defined land use intensification scenarios for a study site in southwestern Niger for two historical situations (1950s and 1990s), and two alternative prospective scenarios (2030s: extensive or intensive). We simulated vegetation growth and horizontal sediment flux of wind erosion for the corresponding landscapes. Results Annual amounts of horizontal sediment flux increased with land management changes from 1950s (nil flux) to 1990s (176 kg m-1 yr-1) and 2030s (452 to 520 kg m-1 yr-1), mostly because of differences in land use, declining soil fertility, and practices decreasing the dry vegetation. For 2030s, intensive scenario
BackgroundIn Mali, the health facility-based prevalence of autism spectrum disorders (ASD) in Mal... more BackgroundIn Mali, the health facility-based prevalence of autism spectrum disorders (ASD) in Mali was 4.5% (105/2,343) and the age of first medical visit for autistic children was around 7 years old in 2018. Parental recognition of developmental abnormalities initiates the early autism detection and diagnosis. We aimed to assess the feasibility of a main study to associate parental concerns with early first medical visits and subsequent ASD diagnostic in Mali.MethodsWe conducted a pilot study from November 2017 to July 2019. We surveyed 57 parents of autistic children aged 3-14 years old.ResultsParents were concerned over verbal communication in 54.1% and reciprocal social interaction in 43.8%. Children with ASD had their first medical visit after 18 months old in 66.7%, ≥ two medical visits in 87.7%, and were identified after 36 months old in 76.8%.ConclusionParental concerns were not significantly associated with early first medical visit and ASD identification. This pilot study ...
Groundwater from hand pump could be a principal supply of potable in the large part of rural area... more Groundwater from hand pump could be a principal supply of potable in the large part of rural areas of Mali. Indeed, it was found that this source was the safest to meet water request in remote areas (i.e., rural) of the low-income countries like Mali. However, groundwater quality is changed once external substances are available to contact with the water table. An evaluation of physicochemical and microbial qualities of hand pump water in the rural commune of Pelengana, Mali, was performed. The parameters analyzed include: physical (temperature, pH, and turbidity), chemical (nitrate, and phosphate) and microbiological (both fecal and total coliform bacteria), using standard procedures of analysis. Moreover, API 20E test was used to determine the identities of isolates. Findings have been compared with the WHO drinking water guidelines (or other) values. All physicochemical parameters in hand pump water samples were within the limit recommended by the WHO guideline (or other) values ...
Background In Mali, the health facility-based prevalence of autism spectrum disorders (ASD) was 4... more Background In Mali, the health facility-based prevalence of autism spectrum disorders (ASD) was 4.5% (105/2,343) and the age of first medical visit for autistic children was around 7 years old in 2018. Parental recognition of developmental abnormalities initiates the early autism detection and diagnosis. Our aim was to investigate if parental concerns were associated with early first medical visits and subsequent ASD diagnostic in Mali. Methods We conducted a pilot study from November 2017 to July 2019. We surveyed parents of 57 autistic children aged 3-14 years old. Results Parents were concerned over verbal communication in 54.1% and reciprocal social interaction in 43.8%. Children with ASD had their first medical visit after 18 months old in 66.7%, ≥ two medical visits in 87.7%, and were identified after 36 months old in 76.8%.Conclusion: Parental concerns were not significantly associated with early first medical visit and ASD identification. A full scale study will be conducted...
Journal of Water, Sanitation and Hygiene for Development, 2018
An assessment of consumer quality perception, as well as some physical and chemical characteristi... more An assessment of consumer quality perception, as well as some physical and chemical characteristics of water samples sourced from wells, boreholes, and rivers in the locality of Pelengana commune, in Mali, was carried out. The World Health Organization (WHO) Guideline (or other) Values (GVs) for drinking water quality was used as a benchmark. One-way analysis of variance (ANOVA) alongside Duncan's multiple comparison tests for significant differences, and Principal Component Analysis (PCA) were used in analyzing differences and correlations regarding the parameters investigated. Results revealed that the majority of the households (61.2%) regarded wells and river water as unsafe for drinking. The physical and chemical quality of water was affected by climatic season. Also, with the exception of iron (average values), the parameters studied met the WHO GVs. Based on the analyzed parameters, the quality of these different water sources is chemically acceptable.
Information on comprehensive evaluation of agricultural innovations is often limited. This study ... more Information on comprehensive evaluation of agricultural innovations is often limited. This study provides an overview of multidisciplinary evaluation of a lowland rice variety, WITA 9 (released in Côte d'Ivoire in 1998), with respect to its agronomic performance, grain quality, resistance to diseases, adoption by farmers, impact on productivity and farmers' income, and marketability. WITA 9 had the highest paddy yield among the tested varieties including an international check (IR 64) and recently developed varieties adapted to this country. WITA 9 had a higher amylose content (26-28%) than others tested. This study confirmed its resistance to bacterial leaf blight, Rice yellow mottle virus (RYMV), and rice blast. A household survey showed that the adoption rate was 24%, its paddy yield advantage was 0.7 t ha-1 , and its adoption increased farmer's income by US$ 91 ha-1 per season. A market study showed that consumers' willingness to pay was higher for WITA 9 than any other locally produced rice variety and comparable to imported rice in one of two markets. We conclude that WITA 9 is an ideal innovation for enhancing productivity and rice import substitution in Côte d'Ivoire. An effective seed delivery system and enhancing farmers' and consumers' awareness of this variety are vital for accelerating impact.
Background: Autism spectrum disorders (ASD) are stigmatizing in Africa and traditional medical pr... more Background: Autism spectrum disorders (ASD) are stigmatizing in Africa and traditional medical practitioners occupy the first line of diagnosis and treatment due to the cultural perception of ASD, and the scarcity of conventional health services in Mali. We aimed to assess the knowledge, attitudes, and practices (KAP) concerning autism among traditional medical practitioners in Bamako, Mali. Methods: We conducted a 6-week cross-sectional survey following a 1-day autism awareness seminary on September 9th, 2017 in Bamako. A questionnaire was designed to assess the KAP regarding autism. To assess their practices, parents of autistic children were asked about their experiences with traditional medical practitioners. Results: Of the 37 study participants 67.60% were males and 56.8% had not heard about autism before the seminary. After the seminary, 73% claimed to understand the diagnosis criteria of autism, but only 16.2% could recall symptoms from all the three domains (reciprocal soci...
Water is an indispensable commodity for the survival of all living beings and for their well-bein... more Water is an indispensable commodity for the survival of all living beings and for their well-being. The objective of this work is to evaluate the level of pollution of different drinking water sources consumed and its link with health in Pelengana commune, Mali. Samples of water were taken from various sources, namely, hand pumps, boreholes, dug wells, and shallow wells for physical, chemical, heavy metals, and bacteriological analyses, using American Public Health Association (APHA) Standard Techniques. Results revealed that the nitrate-nitrogen (NO3−N) values of the water samples from the different water sources had concentrations exceeding the United States Environmental Protection Agency's (US-EPA) regulation of 10 mg/L, as well as World Health Organization Guideline for Drinking Water Quality (WHO GDWQ) (11 mg/L). The same applies to heavy metals such as Cd, Pb, and Fe, in which, concentrations exceed their allowable limits in certain locations. Moreover, apart from water s...
This paper presents data collected in 2013, 2014 and 2015 on the cultural practices and agronomic... more This paper presents data collected in 2013, 2014 and 2015 on the cultural practices and agronomic performance of cropping systems in 500 lowland rice fields located in five regions of three West African countries, Benin, Mali and Sierra Leone. Data were collected in two stages. In the first stage, the main regions containing inland valleys were identified in each of the three countries and the most cultivated inland valley in each region was selected. Weather data were obtained from weather stations located close to the selected inland valleys. In regions with no weather stations, Tinytag data loggers were installed in the inland valleys to collect data on temperature, rainfall and relative humidity. In the second stage, the location and size of all the farmers' fields in each inland valley were determined using GPS devices. In 2013, soil samples were collected in each farmer's field and the soil physical-chemical properties were determined. Agronomic and socioeconomic surveys were conducted to collect data on cultivated crops, crop sequences and management techniques using questionnaires and informal interviews. Crop yields were determined in each farmer's field in the growing season. The database contains a total of 131 variables divided into 9 themes: field characteristics, land preparation, field maintenance, irrigation, residue management, soil
In the Sahel, climate change and demographic growth are raising major concerns about the ability ... more In the Sahel, climate change and demographic growth are raising major concerns about the ability of crop yields to support the local population. Agropastoral management affects wind erosion (e.g., through crop residue management and tillage practices, which modify surface characteristics), which itself substantially affects soil fertility and thus crop yields. There is therefore a need to assess the potential impact of the main Sahelian cropping practices – like sowing, manuring, and crop residue management – on wind erosion. Using a modeling approach adapted to an experimental site located in southwestern Niger over the period 2006–2012, and scenarios that describe a set of agropastoral practices, the impacts of these practices on wind erosion are simulated and compared. The results indicate that horizontal fluxes differ by a factor of 10 among scenarios, with annual horizontal fluxes ranging from 121 to 1,317 kg m−1. Modeled wind erosion is most sensitive to the mass of crop resid...
Luxuriant weed growth destroying rice crops is a major problem in tropical Africa. The objective ... more Luxuriant weed growth destroying rice crops is a major problem in tropical Africa. The objective of this study was to determine the critical period of weed infestation in upland rice varieties in order to enable the development of more precise weed management recommendations for farmers. The effects of 10 differing periods of weed management on upland rice yield were studied in experiments with five rice varieties (three interspecific NERICA: NERICA1, NERICA2, and NERICA4) and the parents (Oryza sativa WAB 56-104 and Oryza glaberrima CG 14) during the 2004 and 2005 rainy seasons at Farako (Mali). INTERCOM model was used to explore the relationship between duration and timing of weed competition and rice crop yield loss, and the applicability of the model in rice cropping based weed management. The critical period of weed infestation determined from the field experiment was similar for the three New Rice for Africa (NERICA) varieties and the O. sativa parent (WAB 56-104), and was between 14 and 42 days after seeding (DAS). For the O. glaberrima parent (CG 14), the critical period was between 28 and 42 DAS. Weed competition either before or after these critical periods had negligible effects on crop yield. During the 2 years, yields of NERICA varieties and WAB 56-104 averaged 2700 and 400 kg ha-1 under weed-free plots and no weed control plots, respectively, indicating a yield loss of 85%. For GG 14, yields averaged 900 and 300 kg ha-1 under weed-free plots and no weed control plots, respectively, resulting in a 66% yield loss. The occurrence and composition of weeds during the two years were similar with a mean of 40% broadleaves, 35% grasses and 25% sedges. The most important weeds were Imperata cylindrica, Cyperus sphacelatus and Digitaria longiflora. During both calibration and testing efforts, the INTERCOM model satisfactorily simulated rice NERICA1 LAI, shoot dry weight and yields (r 2 ranging from 0.71 to 0.87). There appears to be room for improvement in the model with regard to the assumption that nutrients are not limiting to crop growth, but the use of the model for simulating the interactions between rice crop yield losses, weed density, and duration of weed competition appears promising. Results of this study can serve as a guide for optimum timing of weed control to maximize upland rice yield in West Africa.
Quantifying wind erosion and dust emissions in the semi-arid Sahel remains challenging because of... more Quantifying wind erosion and dust emissions in the semi-arid Sahel remains challenging because of the large seasonal and interannual dynamics of surface properties. The increasing conversion of rangelands into croplands raises issues for quantifying wind erosion over these two contrasted surfaces. Whereas wind erosion models have been so far applied to these two surface types separately, this study proposes a common modeling approach to represent the horizontal flux from Sahelian rangelands and croplands. Pair simulations of both typical Sahelian land surface types investigate the horizontal flux due to wind erosion over a 3-year period for two instrumented sites in Mali and Niger. Two different vegetation models simulate the specific phenology and growth of a rangeland grass and a millet crop. These models also account for the local cropping and pastoral practices. Compared to field measurements, the vegetation cover is satisfyingly simulated by the models, especially the strong seasonal dynamics. Specific parameterizations of the aerodynamic surface roughness length (Z 0) as a function of vegetation variables are established using measurements from the two sites. The simulated horizontal flux turns out to be higher for a cropland than for a rangeland by approximately a factor 1.5, implying that increasing Sahelian cropped areas would increase dust emissions from the Sahel. This difference is mainly due to the time shift between grass and millet growth: the latter starts growing about 2 to 3 weeks later than annual grass. The amount of dry vegetation remaining during late dry season is also important for Sahelian wind erosion.
Dans la région de Niamey, les mares et lacs apparus au cours des six dernières décennies sont men... more Dans la région de Niamey, les mares et lacs apparus au cours des six dernières décennies sont menacés de comblement du fait d'un fort taux de sédimentation de plus 4 cm par an. Les surfaces sableuses cultivées couvrant l'essentiel de leurs bassins versants sont particulièrement sensibles à l'érosion éolienne et à l'érosion hydrique. L'objectif de ce travail a été d'estimer la part des apports éoliens dans le comblement d'un de ces lacs, Bangou Bi, à travers des mesures directes de flux de dépôts dans ce lac et de flux d'érosion éolienne sur des surfaces cultivées typiques et nues. Ainsi il est apparu que les dépôts éoliens sur Bangou Bi suivent une dynamique imposée par la cyclicité de l'érosion éolienne des sols nus et cultivés et proviennent à plus de 70 % de l'érosion locale de ces sols. Cependant, ces dépôts ne représenteraient qu'une épaisseur annuelle maximum de 400 µm et apparaissent donc négligeables dans le comblement actuel des mares principalement lié à l'érosion hydrique.
Au Sahel, l’érosion éolienne se développe particulièrement sur les surfaces cultivées. La présent... more Au Sahel, l’érosion éolienne se développe particulièrement sur les surfaces cultivées. La présente étude vise : 1) à quantifier les résidus de culture sur les champs traditionnels pour en déterminer leurs impacts sur l’intensité des flux d’érosion éolienne ; 2) à déterminer le rôle de l’érosion éolienne dans le développement des croûtes d’érosion d’horizon B et à déterminer en retour l’impact de cet encroûtement sur le flux d’érosion éolienne ; 3) à tester le rôle que pourraient jouer des aménagements de type bandes enherbées sur des sols nus très sensibles. Six années de mesures de flux d’érosion éolienne ont été entreprises à Banizoumbou dans le sud-ouest du Niger. Celles-ci ont permis de montrer que les résidus de culture protègent la surface des champs de l’érosion éolienne pendant la saison sèche (janvier – avril) et la diminuent significativement (de plus de 3 fois) au début de la saison des pluies (mai – juillet). Cependant, en dessous d’un seuil de 100 kg.ha-1 de recouvremen...
Recent lakes appeared in the vicinity of Niamey in response to environmental changes in Sahel are... more Recent lakes appeared in the vicinity of Niamey in response to environmental changes in Sahel are good recorders of recent climate dynamics. This work is a preliminary analysis of sediments cored in a recent lake (<50 years) aiming to understand the effects of global change and human pressure on its watershed. In the long term, it should produce a paleoenvironmental model to interpret similar oldest lake sediments in the same area. The BK-08-02 core was setting apart in the lake Bangou Kirey (N13°30’ E2°13’) with a UWITEC corer. XRF, spectrophotometry, micro-particle size analysis and magnetic susceptibility were applied to the core. Laminated sediments from Bangou Kirey shows a good time resolution since sediment fluxes are higher than 2 cm yr-1. The lamination is supposed to correspond to seasonal and intra-seasonal dynamics of sediment flux. The increase of rainy season layer thickness on the top of the core should indicate an increase in runoff intensity linked to anthropogen...
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Papers by Amadou Toure