Inner Niger Delta Research Articles

Les grands aménagements sur le fleuve Niger : atout pour le Mali ou facteur de vulnérabilité pour ses populations rurales ?

Les infrastructures construites sur le fleuve Niger depuis le milieu du XXe siècle ont contribué à la création de nouvelles activités économiques pour le pays. Cependant, l’extension récente de l'Office du Niger soulève des questions sur la place de l’agriculture familiale dans le modèle de développement promu. En outre, les communautés en aval, comme dans le Delta intérieur du Niger, sont affectées par les changements environnementaux liés au développement des infrastructures. L'étude de ces deux zones emblématiques montre la nécessité d'examiner d'une manière plus approfondie la vulnérabilité des populations rurales au moment d’établir les options de politique de développement d’un grand bassin tel que celui du fleuve Niger.

The Archaeology of Social Organisation at Tongo Maaré Diabal

Since the 1970s, research on the first millennium AD in the Middle Niger has shed light on a fascinating episode of the world's history. Written records and oral histories hint at the existence of large polities and great wealth, while archaeological research has documented the development of urbanism and long-distance trade networks, and attempted to locate legendary capitals and trace migrations. In contrast, we know very little about the life of non-urban localities and societies living at the edge of the great 'empires'. This thesis takes an explicitly social focus to archaeology in the Middle Niger. To this end, excavations were carried out at the medium-sized tell site of Tongo Maare Diabal (c. AD 400-1100) near Douentza, Mali. Rather than exploring the site's deep stratigraphy, which had already been done by K.C. MacDonald and T. Togola in the 1990s, these excavations opened a large area of the uppermost occupation horizon. Building on this excavation strategy, and using a household- level approach to a wide range of artefactual evidence, this thesis is able to explore themes such as sociocultural diversity, the social use of space, craft specialisation, connections and trade on a local, regional and supra-regional scale. Tongo Maare Diabal is shown to have been the densely populated home of several lineage groups, which formed part of a network of sites in a culturally diverse region. The site's inhabitants were involved in the production and processing of iron on a large scale, which they probably traded with urbanised areas in the Inland Niger Delta, and upheld a network of influences and connections spanning the Middle Niger and the Niger Bend, even reaching across the Sahara.

L'occupation humaine de la vallée du Guringin (plaine du Séno, Mali)

Recent archaeological survey conducted in Mali in the Guringin Valley, located in the Séno Plain, as well as at the top of the nearby Bandiagara Escarpment, has produced evidence allowing the characterisation of numerous settlement sites and locations at which prehistoric metallurgy was practised. The latter have abundant surface material, mainly consisting of ceramics that show a considerable diversity of decoration. Analysis of the surface pottery assemblages, complemented by that of stratified assemblages from a test pit at one of the sites, indicates important inter-site differences. The results suggest that water, a rare and precious resource in this sandy Sudano-Sahelian plain, attracted the settlement of different populations from Neolithic times to the present, with a particular density of occupation during the first and early second millennia AD. Groups of sites of similar modest size evoke the rural settlements of the Méma area of Mali more than the settlement clusters of the Inland Niger Delta, which are defined by large sites surrounded by satellite settlements in a context of proto-urbanisation.

Cattle in the West African savanna: evidence from 1st millennium CE Kirikongo, Burkina Faso

The West African sahel and savanna are today home to diverse cattle breeds derived from complex social, political and environmental processes over at least the past four thousand years. Current evidence from the sahel and its floodplains indicates multiple sizes of cattle over time that may correspond to modern breeds. However, little is known about the cattle further south in the savanna, such as the West African Shorthorn. These humpless cattle are well adapted to the environmental conditions of more humid zones, including their significant resistance to trypanosomiasis, or sleeping sickness. In this paper I present new archaeozoological data from the Iron Age village of Kirikongo, Burkina Faso (100–1700 CE) that indicate the presence of small cattle in the 1st millennium CE similar in size to West African Shorthorn. These results are contextualized through comparisons with other archaeological sites and environmental data in Central West Africa, suggesting that small cattle are generally associated with the savanna environment over time, and their distributions may have oscillated with climatic changes. Lastly, interregional processes are assessed given Kirikongo’s evidence for small savanna cattle in western Burkina Faso and their subsequent adoption in the Inland Niger Delta of Mali.

Thermal remote sensing of water under flooded vegetation: New observations of inundation patterns for the ‘Small’ Lake Chad

Lake Chad at the border of the Sahara desert in central Africa, is well known for its high sensitivity to hydroclimatic events. Gaps in in situ data have so far prevented a full assessment of the response of Lake Chad to the ongoing prolonged drought that started in the second half of the 20th century. Like many other wetlands and shallow lakes, the ‘Small’ Lake Chad includes large areas of water under aquatic vegetation which needs to be accounted for to obtain the total inundated area. In this paper, a methodology is proposed that uses Meteosat thermal maximum composite data (Tmax) to account for water covered by aquatic vegetation and provide a consistent monthly time series of total inundated area estimates for Lake Chad. Total inundation patterns in Lake Chad were reconstructed for a 15-yr period (1986–2001) which includes the peak of the drought (86–91) and therefore provides new observations on the hydrological functioning of the ‘Small’ Lake Chad. During the study period, Lake Chad remained below 16,400 km2 (third quartile ∼8800 km2). The variability of the inundated area observed in the northern pool (standard deviation σnorthern pool = 1980 km2) is about 60% greater than that of the southern pool (σsouthern pool = 1250 km2). The same methodology could be applied to other large wetlands and shallow lakes in semi-arid or arid regions elsewehere using Meteosat (e.g. Niger Inland Delta, Sudd in Sudan, Okavango Delta) and other weather satellites (e.g., floodplains of the Lake Eyre Basin in Australia and Andean Altiplano Lakes in South America).

Breastfeeding and weaning in a village in the Niger Inland Delta, Mali

The aim of the study was to investigate the breastfeeding and weaning customs and their influence on the survival of infants in the village of Niafunké, Mali. A questionnaire with 22 questions was put to 30 mothers, 15 traditional birth attendants, and 5 midwives. All the mothers used colostrum. However, before breastfeeding was initiated the children were given date juice, which constitutes a considerable infection risk. Weaning was started at the age of 6 to 9 months. The breastfeeding and weaning customs are largely satisfying; nevertheless, the child mortality before the age of 5 years was extremely high, at 56 children out of 131 born. The majority of these, 40, died during their first year of life. The infant mortality showed two periods of greatly elevated death rate: right after birth and during the period of weaning. The mortality after birth may depend on the lack of educated midwives as well as infections caused by water being given with the breast milk. The mortality at weaning obviously depends on poor hygienic conditions, possibly combined with a documented insufficient zinc intake weakening the immune system. Abrupt weaning practised when a new pregnancy is experienced is also a contributing factor. The breastfeeding may be interrupted over a single day, causing both physical and mental stress for the child. The mothers' information about breastfeeding and weaning comes from a number of sources: the parents, the traditional birth attendants, religious authorities, and the radio, which seems to have a good reach into the society.

Wetland inundation dynamics in a model of land surface climate: Evaluation in the Niger inland delta region

Observed river gauging data show significant evaporative losses from the land and water surface in the Niger inland delta. These losses indicate an important potential feedback between the land surface and atmosphere. Moreover, the reduction in river flow downstream of the wetland has clear implications for water management in the region and beyond. Here we have modeled the evaporative losses that occur over the Niger inland delta by adding an overbank flow parameterization to the Joint UK Land‐Environment Simulator (JULES) land surface model. The hydrological component of this model comprises a probability‐distributed model of soil moisture and runoff production coupled with a discrete approximation to the one‐dimensional kinematic wave equation to route river water downslope. We use subgrid‐resolution topographic data to derive a two‐parameter frequency distribution of inundated areas for each grid box which we then employ to represent overbank inundation in the model. The model was driven using data from the ALMIP experiment (ALMIP stands for AMMA Land surface Model Intercomparison Project, wherein AMMA stands for African Monsoon Multidisciplinary Analyses). The model reproduces the salient features of the observed river flow and inundation patterns; these include significant evaporative losses from the inundated region accounting for doubling of the total land‐atmosphere water flux during periods of greatest flooding. Our predictions of inundated area are in good agreement with observed estimates of the extent of inundation obtained using satellite infrared and microwave remote sensing.

Ecological Modeling of the Spatial Distribution of Wild Waterbirds to Identify the Main Areas Where Avian Influenza Viruses are Circulating in the Inner Niger Delta, Mali

Predicting areas of disease emergence when no epidemiological data is available is essential for the implementation of efficient surveillance programs. The Inner Niger Delta (IND) in Mali is a major African wetland where >1 million Palearctic and African waterbirds congregate. Waterbirds are the main reservoir of Avian Influenza Viruses (AIV). Our objective was to model their spatial distribution in order to predict where these viruses would be more likely to circulate. We developed a generalized linear model (GLM) and a boosted regression trees (BRT) model based on total aerial bird counts taken in winter over 6 years. We used remotely sensed environmental variables with a high temporal resolution (10 days) to predict the spatial distribution of four waterbird groups. The predicted waterbird abundances were weighted with an epidemiological indicator based on the prevalence of low pathogenic AIV reported in the literature. The BRT model had the best predictive power and allowed prediction of the high variability of waterbird distribution. Years with low flood levels showed areas with a higher risk of circulation and had better spatial distribution predictions. Each year, the model identified a few areas with a higher risk of AIV circulation. This model can be applied every 10 days to evaluate the risk of AIV emergence in wild waterbirds. By taking into account the IND's ecological variability, it allows better targeting of areas considered for surveillance. This could enhance the control of emerging diseases at a local and regional scale, especially when resources available for surveillance programs are scarce.

Feedbacks on convection from an African wetland

The Niger Inland Delta in Mali floods every year in response to rain falling hundreds of kilometers upstream. This study examines the remote hydrological feedback between rainfall, fluvial inundation, and new convective storms. A satellite thermal infra‐red dataset spanning 24 years is used to quantify both temporal variability in wetland extent, and the response of cloud cover to the wetland during August and September. The daytime initiation of convective storms is found to double during periods of inundation, consistent with a hypothesised “wetland breeze” effect. A signal of enhanced cloud cover propagates hundreds of kilometers westwards, linked to increased numbers of long‐lived Mesoscale Convective Systems emanating from the wetland region. This effect raises the possibility that changes in upstream water use could have a climatic impact over a wide area.

The Pre- and ProtohistoricToguéof the Niger Alluvial Plain, Mali

The Inland Niger Delta in Mali is scattered with thousands of tell-like dwelling mounds that testify to the rich archaeological heritage of this attractive occupation area. The results of archaeological research suggest an occupation history of more than two millennia in which large urban settlements such as Djenné-Djeno and Dia play a central role. Regional surveys have revealed primary information on the vast rural hinterland of these extensive cities, but little is known about the structure and evolution of this considerable settlement system. The aim of the re-examination of 128 sites in the southern part of the Niger alluvial plain was to obtain an understanding of intersite relations based on sites' chronological, functional, socio-economic, and hierarchical differentiation and their participation in different trade networks. For the research it was crucial to find a method to date the last occupation period of the sites using surface remains. The results of the study emphasise the former occupants' preference for the most elevated landscape units close to fertile pastures, good cultivation grounds, and extensive fishing potential for their settlement sites. The occupants' ability to distribute and exchange agricultural surplus for luxury goods – imported via regional, inter-regional and trans-Saharan trade networks – is impressive, showing that they were able to compete with occupants of the large urban centres. Although the rural sites were much smaller than Djenné-Djeno and Dia, they were well connected. The rural hinterland apparently played an important role in most of the great West African empires. Population densities of the Inland Niger Delta were high for a long time, until the trade routes changed in the 15th century AD and the region became socio-politically unstable. This led to the abandonment of settlements, first around the urban settlements, and later also in the rural hinterland. The present-day occupation of the region is only a poor reflection of its impressive past.

Zinc in Soils, Crops, and Meals in the Niger Inland Delta, Mali

Zinc deficiency is a problem in developing countries and not least so in Africa. This concerns both agriculture and human food provision. Zinc deficiency in soils may severely decrease yields, whereas insufficient zinc in food intake primarily affects the immune defense, notably in children. The present investigation concerned zinc availability in soils, crops, and food in the Niger inland delta in Mali. Agricultural soils are largely deficient in plant-available zinc, however, soils in close vicinity to habitation show elevated zinc concentrations. The zinc concentrations in crops are low; in rice, they are about half of reference ranges. Zinc intake assessed from a number of sampled meals was about half the recommended requirement. When zinc concentration is higher phytate was also high, which made the zinc less available. In spite of a recorded sufficient intake of iron, anemia is common and is most likely because of the high phytate concentration in the cereal-dominated diet. Increasing zinc and iron availability would be possible through the use of malting, fermentation, and soaking in food preparation. Finally, in the long run, any trace element deficiency, especially that of zinc in agricultural soils needs to be amended by addition of appropriate amounts in commercial fertilizers.

Farmer–herder conflicts, pastoral marginalisation and corruption: a case study from the inland Niger delta of Mali

This study aims to explain a farmer–herder conflict in the inland Niger delta of Mali. We focus on the interests and motivations of the actors involved in the conflict and the rent seeking of the local administration in handling the conflict. Since independence, the customary pastoral leaders (the jowros) have gradually lost power and wealth to the benefit of previously underprivileged farmers (the rimaybé). We argue that this process is mainly the result of national policies and laws giving priority to agricultural development at the expense of pastoralism. The result has been large‐scale conversions of dry season pastures to rice fields. This pastoral marginalisation also results in increased land use conflicts between herders and farmers. In addition, rent seeking by local officials is perpetuating land use conflicts in the area. Hence, officials are benefiting from conflicts, while especially pastoralists, but also farmers, are losing out. The droughts of the 1970s and 1980s, leading to a more rapid encroachment of rice fields on pastures, as well as the power vacuum that emerged in the early days of the decentralisation process, further aggravated land disputes. Finally, we use this case study to call for an inclusion of issues of rent seeking and corruption more centrally in political ecology.

Flood monitoring in a semi-arid environment using spatially high resolution radar and optical data

The geographic term “Niger Inland Delta” stands for a vast plain of approximately 40,000 km 2, which is situated in the western Sahel (Republic of Mali). The Inland Delta is affected by yearly inundation through the variable water levels of the Niger–Bani river system. Due to a good availability of (surface) water, the ecosystem at the Niger Inland Delta serves as resting place stop-over for many migrating birds and other wildlife species as well as economic base for farmers and pastoral people. To foster the sustainable usage of its natural resources and to protect this natural heritage, the entire Niger Inland Delta became RAMSAR site in 2004. This paper aims to test to which extent texture analysis can improve the quality of flood monitoring in a semi-arid environment using spatially high resolution ASAR imaging mode data. We found the Gray Level Dependence Method (GLDM) was most suitable proceeding for our data. Several statistical parameters were calculated via co-occurrence matrices and were used to classify the images in different gradation of soil moisture classes. In a second step we used additional information from spatially high resolution optical data (ASTER) to improve the separability of open water areas from moisture/vegetated areas.

A First Assessment of Zinc Intake in Niger Inland Delta, Mali

A First Assessment of Zinc Intake in Niger Inland Delta, Mali

Late Holocene economic specialisation through aquatic resource exploitation at Kobadi in the Méma, Mali

AbstractFollowing the last humid phase of the Late Holocene, human groups left the Saharan latitudes of northern Mali at around 2500 cal. years BC to settle further south. The Kobadi population was among the first Neolithic human groups to enter the Niger Inland Delta in central Mali. People adapted to their new environment by intensifying one of their former subsistence practices, namely fishing. The rich and diversified ichthyofauna exploited was dominated by large Nile perches and a variety of catfish taxa. It testifies to relatively stable hydrological conditions: a fluvial lake which was probably linked permanently to the main Niger River. Fish were caught with harpoons and probably also with diverse fishing devices such as nets, baskets and fences. Preparation processes prior to cooking cannot be determined, but fish were probably cooked on hot coals or stones, the left‐overs of the meals being discarded randomly at the site.Intense exploitation of the aquatic environment near Kobadi provided an abundant, secure and predictable source of protein. Besides fish and riparian mammals, reptiles such as turtles, monitors and crocodile were hunted. Domestic cattle provided milk and/or meat. These animals were either raised at the site or obtained by means of exchange with pastoral groups roaming the hinterlands. From the 2nd millennium BC, the focus on aquatic resources at Kobadi, mostly through the intensification of fish exploitation, may demonstrate the beginning of economic specialisation in the Niger Inland Delta. Copyright © 2008 John Wiley & Sons, Ltd.

Aeolian and fluviolacustrine landforms and prehistoric human occupation on a technically influenced floodplain margin, the Méma, central Mali

AbstractThe Mema is a semi-arid region in central Mali with a rich archaeological heritage indicating the former existence of large urban settlements. The archaeological data suggest millennia of occupation history of the Méma preceding relatively sudden abandonment by the 14th or 15th century AD. Population numbers have remained low since then and today’s human presence in the area is sparse and largely mobile. Geomorphologically, the Méma can be characterized as a graben hosting various generations of aeolian landforms and (presently mostly dry) interdunal channels and lakes, linked to the neighbouring Inland Niger Delta floodplain. Given this setting, and the variability of the Sahelian climate, climatic contributions to the region’s sudden abandonment are likely. A geomorphological survey of the region, and interpretation of the observed geomorphological record in terms of climatic history, aimed at providing a basis for understanding the intensive occupation and subsequent abandonment of the Méma. The results of this study underscore dramatic Holocene climatic variability, leading to the region’s present geomorphological diversity, but also suggest that neotectonic movements constitute an important additional cause of regional desiccation. Both may have encouraged prehistoric people to abandon the Méma after a long period of occupation.

The spatial distribution of Anopheles gambiae sensu stricto and An. arabiensis (Diptera: Culicidae) in Mali

Variations in the biology and ecology and the high level of genetic polymorphism of malaria vectors in Africa highlight the value of mapping their spatial distribution to enhance successful implementation of integrated vector management. The objective of this study was to collate data on the relative frequencies of Anopheles gambiae s.s. and An. arabiensis mosquitoes in Mali, to assess their association with climate and environmental covariates, and to produce maps of their spatial distribution. Bayesian geostatistical logistic regression models were fitted to identify environmental determinants of the relative frequencies of An. gambiae s.s. and An. arabiensis species and to produce smooth maps of their geographical distribution. The frequency of An. arabiensis was positively associated with the normalized difference vegetation index, the soil water storage index, the maximum temperature and the distance to water bodies. It was negatively associated with the minimum temperature and rainfall. The predicted map suggests that, in West Africa, An. arabiensis is concentrated in the drier savannah areas, while An. gambiae s.s. prefers the southern savannah and land along the rivers, particularly the inner delta of Niger. Because the insecticide knockdown resistance (kdr) gene is reported only in An. gambiae s.s. in Mali, the maps provide valuable information for vector control. They may also be useful for planning future implementation of malaria control by genetically manipulated mosquitoes.

The Patterns and Meaning of a Great Lake in West Africa

The cartographical history of Africa has often left much to the imagination. The idea of a great inland lake along the Niger River in West Africa, for example, has had a rich tradition in written accounts and on maps from Ptolemy onwards. One tendency was to dismiss the notion that any such body of water existed; another was to find divers ways of reconciling tradition and the sparse scattering of new 'facts' that reached European mapmakers. The fundamental problem was ignorance about the hydrology of the interior of Africa, especially in the region of the Niger River. Not until the nineteenth century was the presumed connection between the Niger and Senegal rivers laid to rest, together with the older view that the Niger flowed underground through the eastern highlands to the Nile. Only then was the Niger's actual course established, flowing first east and then, after a great bend, south to debouche into the Gulf of Guinea.1 While the attention of historians focused mostly on the African coastline and the eastern lakes, the early maps of West Africa had regularly showed a prominent inland lake on the southern edge of the Sahara. The cartographical history of this lake has invited further investigation. In this paper we ask how did the image originate, by what physical feature could it have been inspired, and why should it have been considered important in the history of the sub-Saharan region. We approached the issue by looking at four hundred primary maps dating from 900 to 1900. The analysis of this database confirmed that one of the most consistent features throughout the archival record was the image of a lake in West Africa within the region of the middle Niger River.2 From maps on which the lake was named (which was not always the case), we have identified numerous toponyms, including Nigrite Palus, Nilides Palolus, Wangara, Sigisma, Guber, Guarda, Bogs of Guarda, Maberia, Nigris Morass, Dibbie Sea, Lake Dibbie and Lake Debo. This analysis has led to the conclusion that whatever the feature was called, and whatever shape it was given, the mapmakers were each attempting to portray a common physical reality. That entity was the fluctuating area of lakes and branching streams in the middle course of the Niger River, between Djenne and Tombouctou known today as the Inland Niger Delta (Fig. 1). The inland delta, as a unique local feature, is shown on modern maps at best as a limited area of swamp at the southern edge of the Sahara. It is rarely given a name and remains mostly unnoticed in the world's view of modern Africa. Yet, the true meaning of this great wetland lies in the fact that it was once home to a thriving civilization centred on an array of specialized urban settlements near Lake Debo, in the vicinity of modern Djenne (old JenneJeno).3 For more than fifteen hundred years Jenne-Jeno had been the focus of one of the

Researching Africa's Past: New Contributions from British Archaeologists

Introduction (Peter Mitchell, Anne Haour and John Hobart) J. Desmond Clark 1916-2002 & Betty Clark 1915-2002 (Ray Inskeep) Understanding hominid landscapes at Makapansgat, South Africa (Anthony Sinclair, Lorna McCraith and Emma Nelson) 'Environmental magnetism': evidence for climatic change during the Later Stone Age using the magnetic susceptability of cave sediments from Rose Cottage Cave, South Africa (Andy Herries and Alf Latham) Anyone for hxaro? Thoughts on the theory and practice of exchange in southern African Later Stone Age archaeology (Peter Mitchell) An old fashioned approach to a modern hobby: fishing in the Lesotho Highlands (John Hobart) Ostrich eggshell beads and the environment, past and present (Chris Wingfield) Hunter-gatherers and the first farmers of prehistoric Ghana: the Kintampo Archaeological Research Project (Derek Watson) Looking forwards by looking backwards: west of Aksum (Jacke Phillips) New light on the Tichitt Tradition: a preliminary report on survey and excavation at Dhar Nema (Kevin MacDonald, Robert Vernet, Dorian Fuller and James Woodhouse) Timbuktu the less mysterious? (Tim Insoll) Islam and alternative religious practices during the second millennium AD in the Inland Niger Delta of Mali (Noemie Arazi) Why these African Walls? Some considerations from Kufan Kanawa, Niger (Anne Haour) The soils of Engaruka: preliminary soil exhaustion tests on a pre-colonial agricultural landscape in Tanzania (Darryl Stump) Recent research on the archaeology of Buganda (Andrew Reid) Iron-smelting and bananas in Buganda (Andrew Reid and Ruth Young) Kings and ancestors: interpreting the past at KoBulawayo, Zimbabwe (Gwilym Hughes and Joseph Muringaniza) Subtidal archaeological investigations in Mombasa's Old Port (Wes Forsythe, Rory Quinn and Colin Breen) The Shire archaeological landscape, northern Ethiopia: towards a strategy of cultural resource management and a workable Sites and Monuments Record (Niall Finneran) African archaeology in Britain: a commentary on current trends and contexts (Paul Lane).

TOBACCO PIPES FROM EXCAVATIONS AT THE MUSEUM SITE, JENNE, MALI

Tobacco pipes are among the most frequently recorded artifacts from historic period sites in West Africa, and can be used to both establish tight chronologies and address issues of social and economic change.This paper is a discussion of the 300-year sequence of tobacco pipes recovered from excavations at Jenne, Mali in 1999. The assemblage, which includes over 300 fragments, is first placed in its historical and archaeological context. The pipes are fully described using a multivariate approach, and the results illustrate a clear sequence. Following a reassessment of Daget & Ligers’ previously proposed pipe chronology for the Inland Niger Delta, the pipes are analyzed using two primary frames of reference. On a broad regional scale, the assemblage is compared with those from sites throughout West Africa, while on the local level possible motivations for the types of changes seen in the assemblage are discussed.