Amadou Abdourhamane Touré

Abdou Moumouni University | UAM · géologie

In Niger, artisanal and scale mining contributes to reducing the poverty of populations in rural areas by injecting considerable monetary income but creates many environmental problems. This study aims to analyze the environmental impacts of artisanal and small-scale mining at the Aouzegueur mining sector, with a view to helping reduce the environm...

This study examines the origin and distribution of clay minerals of the pedological horizons of Kori Ouallam watershed (south-western Niger). It is based on field sampling campaigns and a series of laboratory analyses. A total of 49 samples were analysed, 28 from surface horizons (0–10 cm depth) and 21 from pedological profiles (0–1 m depth). The s...

In West Africa, lakes and reservoirs play a vital role as they are critical resources for drinking water, livestock, irrigation and fisheries. Given the scarcity of in situ data, satellite remote sensing is an important tool for monitoring lake volume changes in this region. Several methods have been developed to do this using water height and area...

Agricultural drought is a complex phenomenon with numerous consequences and negative implications for agriculture and food systems. The Sahel is frequently affected by severe droughts, leading to significant losses in agricultural yields. Consequently, assessing vulnerability to agricultural drought is essential for strengthening early warning syst...

Dust emission by wind erosion is a worldwide phenomenon that threatens sustainable development and population wellness in areas where anthropogenic activities develop. However, uncertainties on the current estimates of dust originating from agricultural activities remain high. This study aims at disentangling the respective roles of meteorology, su...

This study examines the effects of restoration of degraded lands on soils physicochemical properties and adaptability of planted woody species over a period of 4‐6 years. It is based on: 1) Physicochemical analyses of soils (granulometry, calcimetry, and organic matter), 2) measures carried out for the dimensioning of anti‐erosion structures, 3) de...

In southeast Niger, the degradation of the environment led to the reactivation of moving dunes that threatens infrastructure, fields, and river with silting. To stabilize the dune cordon of Namaro, which is heavily cultivated and grazed, anti-erosion devices: living hedges and grassland has been developed. The objectives of this work are then to ch...

Study Region: Middle Niger River Basin (MNRB), Ansongo to Niamey, Sahel, West Africa. Study Focus: Although MNRB hydrology and the red flood phenomena have been addressed in the past literature, water quality parameters and suspended particulate matter (SPM) dynamics remain poorly known. SPM impacts dam silting, exacerbating flooding, and microbial...

ContextWind 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 cha...

The objective of this study is to analyze the dynamics of the Niger riverbed occupationin Niamey. The methodology used is based on the processing of satellite images and their interpretation. The results showed, between 1973 and 2018, a reduction of the free riverbed (from 2415.28 ha in 1973 to 1952.88 ha in 2018 i.e. a regression of 29.91 ha) foll...

In the Sahel, exacerbated soils degradation is an ecological indicator of ecosystem vulnerability. This study examines the effects of restoration of degraded lands on soils physicochemical properties and adaptability of planted woody species over a period of 4-6 years. It is based on: 1) Physicochemical analyses of soils (granulometry, calcimetry,...

In order to contribute to the valuation of clay materials from the Zinder Region, the clays taken from the quarry and used for the pottery of Mirriah have been characterized from a physico-chemical and mineralogical point of view. So the five samples were taken and the composite sample representative of the quarry were subjected to chemical and min...

In the eastern part of Niger, which is arid to semi-arid, market gardening production systems are based on temporary, semi-permanent to permanent basins or ponds and lakes. In Guidimouni, in the Damagaram, the market gardening production system is associated with two permanent lakes, located side by side. The objective of the present study was to a...

In order to characterizeclays of the Zinder region, 20 samples were taken from the quarries of Magaria, Mirriah, Guidimouni and Kolleram and four composite samples were made and representative of the quarries. These samples were subjected to chemical and mineralogical analyzes. Chemical analysis shows that the materials from these four quarries are...

Au sahel, le processus de l'érosion hydrique est un marqueur majeur de la dégradation des terres. Cette étude porte sur l'érosion hydrique en nappe sur des toposéquences à des échelles de temps récente et actuelle au niveau des bassins versants de Boubon et Louguel. L'approche méthodologique a été basée sur un dénombrement des arbres et des bas fou...

Les mouvements de terrain sont des phénomènes capables de causer d'importants dommages. Cette étude a pour objectif de caractériser les processus qui sont à l'origine du déclenchement des éboulements des corniches de Yantala et Gamkalley. Ainsi, la méthodologie adoptée a consisté à des caractérisations pétrographiques et structurales, à l'identific...

In the Sahel, wind erosion increases the vulnerability of sandy soil through the removal of the finest and most fertile fraction of the soil, including nutrients, potentially limiting vegetation development. To provide experimental evidence of the role of different land uses on wind erosion, measurements of horizontal sand fluxes and associated met...

L’ensablement est un problème majeur pour des plans d’eau et des infrastructures. Dans le Manga, au sud-est du Niger, l’érosion éolienne est vue comme le principal responsable de cet ensablement. Cependant l’érosion hydrique, négligée jusque-là, se manifeste par des ravines observées sur les flancs des dunes. Le sable ainsi mobilisé est déposé dans...

Depuis 2006 trois stations de suivi des poussières désertiques, installées dans le cadre du programme AMMA et pérennisées au sein du SNO INDAAF (cf Poster) fournissent la vitesse, la direction du vent et la pluviométrie au pas de temps de 5 mn. Une analyse détaillée de ces données collectées sur 10 années au Mali et au Niger a permis de décrire le...

The semi-arid Sahelian region is particularly prone to wind erosion due to low and variable annual precipitation producing low vegetation cover with a high interannual variability. Surfaces traditionally devoted to livestock grazing are used as croplands, increasing the proportion of bare surface unprotected from wind erosion. Wind erosion could si...

Au Sahel, l'érosion éolienne constitue un facteur important de la dégradation de l'environnement. Elle cause des pertes en terre et réduit la productivité des sols. Ce travail conduit à Banizoumbou (sud-ouest du Niger) vise à quantifier les flux d'érosion éolienne grâce à l'utilisation de pièges à sable de type BSNE entre 2006 et 2014 sur une parce...

In the Sahel, under 500 mm of annual rainfall, wind erosion is an important factor leading to the degradation of the environment. It causes soil losses and reduces soil productivity. This work, conducted in the southwestern Niger, aims at quantifying wind erosion fluxes using BSNE sand traps. The study was conducted, from 2006 to 2014, on a plot fi...

The soils' degradation negatively affects the agricultural production in Niger. The objective of this study is to characterize the physiochemical potential of the degraded soils of Boubon. Thus, four samples were taken for various surface states in order to determine their physical and chemical characteristics. Otherwise, the evolution of the densi...

In the Sahel, wind erosion increases the vulnerability of sandy soil by the removal of the finest and most fertile fraction of the soil, including nutrients, which limits vegetation development. The aim of this work is thus to provide experimental evidences of the role of different land uses on wind erosion in order to better quantify their impact...

Xth International Conference on Aeolian Research

The floods are increasingly frequent and disastrous in the Sahel. This study aims at characterizing the role of the soil in the genesis and the consequences of the floods in Niamey. Thus, pits were dug in the districts of Zarmagandey, Banguisto and Saga in order to determine among others the parameters of permeability, swelling, and the granulometr...

The floods are increasingly frequent and disastrous in the Sahel. This study aims at characterizing the role of the soil in the genesis and the consequences of the floods in Niamey. Thus, pits were dug in the districts of Zarmagandey, Banguisto and Saga in order to determine among others the parameters of permeability, swelling, and the granulometr...

Tomato is the most widely grown vegetable in Africa. It goes into the preparation of many dishes, given its nutritional importance due to its content in active substances such as vitamins A and C, iron and phosphorus. Experiments were set up on a vegetable growing site at INRAN’s headquarters. This consisted in three trials with different treatment...

This study was conducted in the rural commune of Simiri, village of SATARA, located north of Niamey (capital city of Niger) at about 70 km. Its general objective is to evaluate the socioeconomic impact of the realization of half-moons and forest benches, their durability as well as their influences on the plantations of Eucalyptus camaldulensis. Th...

At south Niger, wind erosion is the main factor of the environmental degradation. The landscape of this area is a juxtaposition of field and follow of different age. This work aimed to quantify wind erosion fluxes and nutrient transfer in relation of soil usage during an entire season. Thus it appeared that wind erosion had an important role in the...

Au Sahel, l'érosion éolienne cause des pertes en terres et en nutriments. Au Niger méridional, cette orme érosion est une cause majeure de la dégradation de l'environnement. Le paysage de ce milieu est dominé par une juxtaposition de surfaces exploitées sous culture pluviale, et de jachères d'âges différents. L'objectif de ce travail est de quantif...

At south Niger, wind erosion makes soil and nutrients losses and it remains a major factor of environmental degradation. The landscape of this area is dominated by a juxtaposition of bush fallow with different age and millet field. The aim of this work has been to quantify : i) wind erosion flux during 9 years on a plot at first cultivated (2006 to...

In the Sahel, climate change and demographic growth are raising major concerns about the ability of crop yields to support the local population. Agro-pastoral management affects wind erosion (e.g. through crop residue management and tillage practices, which modify surface characteristics), which itself substantially affects the soil fertility, and...

Au Sahel, l'érosion hydrique cause des dommages majeurs aux terres exploitées dans les systèmes agraires. L'objectif de ce travail a été de quantifier la dynamique spatio-temporelle d'un processus de cette érosion, le ravinement, à l'échelle du bassin versant du lac Kongou situé au Nord-est de Niamey. L'étude a été fondée sur une cartographie diach...

In Niamey region, ponds and lakes formed in the past six decades are being filled with a sedimentation rate of 4 cm per year. The cultivated sandy soils covering their watershed are prone to wind and water erosions. This work aimed to estimate the proportion of aeolian deposits in the filling of one of these lakes, Bangou Bi, by the means of aeolia...

Dans le Manga (Sud-est du Niger), l'un des effets de la pression anthropique et de la variation climatique se traduit la disparition de la végétation qui a pour principale conséquence la mobilisation du sable dunaire. L'objectif de ce travail est de caractériser l'érosion éolienne au niveau des dunes vives. Spécifiquement, il s'agit de i) mesurer l...

l’érosion hydrique, le ravinement, devient de plus en plus important pour lutter efficacement contre l’ensablement.

Au sud-ouest du Niger dans les environs de Niamey, plusieurs milliers de bas fourneaux à usage unique ont été recensés. Une étude archéologique menée sur une trentaine de structures de bas fourneaux et de leurs scories a révélé la présence de quatre procédés de réduction du fer : trois de type scorie piégée et un de type scorie coulée. Les bas four...

The process of desertification is accelerated in the northern part of Lake Chad basin since the early 1970. Those processes linked to the recurrent drought and a heavy human pressure induced a great environmental damages. So this study based on diachronic cartography (1957, 1975 and 2007) aimed to describe and quantify the degradation dynamics in t...

L’envasement des cours d’eau est une des graves conséquences des changements climatiques et des fortes pressions anthropiques au Sahel. Des taux de comblement de l’ordre de 2 à 3 cm/an ont été mis en évidence dans ceux de la région de Niamey (Sud-Ouest Niger). Dans ce contexte, ce travail est fait pour déterminer les impacts des variations piézomét...

La faible pluviosité dans la région de Zinder, ville sahélienne recevant moins de 500 mm de pluies par an et la situation de celle-ci sur un socle cristallin jeune, affleurant et peu perméable sont les principaux facteurs limitant la disponibilité de l'eau potable pour la ville. La faible disponibilité de la ressource implique alors des difficultés...

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 applie...

Le Sahel est une région en équilibre précaire, très sensible aux variations climatiques et aux changements environnementaux. La démographie galopante combinée aux pratiques agricoles, par la conversion des savanes en terres de culture, a favorisé une forte détérioration du milieu. Ce travail visait à quantifier les changements environnementaux, et...

Les changements climatiques et la pression anthropique imposent une dynamique dans les environnements sahéliens. Cette étude se propose d‟analyser la dynamique spatio-temporelle de l‟occupation des sols dans les régions de Maradi et Diffa (Niger) afin de faire la part respective et relative des différents facteurs intervenant dans la dynamique du m...

Since the drought of the early 1970s, the Niger part of the Lake Chad Basin has undergone significant changes. Its environment has evolved considerably, with land cover and use (cultivation, grazing) experiencing significant momentum. This change in land use has led to a decrease in natural habitats (savannas and forests), thereby increasing the vu...

Les plateaux de la rive occidentale du fleuve Niger sont recouverts de lignes et de tas de pierres sèches alors que ces surfaces tabulaires sont aujourd'hui dépourvues de toutes cultures. Le sol du plateau est constitué d'un horizon argilo-sableux visible uniquement dans la zone où ces structures sont présentes. Elles témoigneraient d'un épierrage...

Dust emitted from soil by wind erosion is a main atmospheric compound in the Sahel. Its impacts on climate, biogeochemical cycles and human health explain the present increasing interest of this topic. The different terms of the dust life cycle (emission, transport, deposition) and the parameters controlling this cycle have to be understood and des...

In the Sahel, crop residues are well known to reduce wind erosion. But these crop residues were studied on controlled experimental plots with amounts much higher than those traditionally encountered on cultivated fields. This work aims i) to monitor crop residues on traditional field and to quantify its influence on wind erosion ii) to characterize...

Biological Soil crusts (BSC) are widespread in semi arid areas like the Sahel where they are colonizing sandy soils prone to water and wind erosions. This study aimed at understanding the effect of BSC on wind erosion. It was performed at the ICRISAT Sahelian Center of Sadore (Niger) in an old fallow. The annual rainfall depth is around 560 mm. The...