Documents found
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72.More information
RÉSUMÉ : En milieu marin, l'appréhension et la maîtrise des échelles de variation spatiale et temporelle représentent une condition indispensable à la compréhension de la dynamique et de la structure des populations. Dans les systèmes d'archipels, ces processus sont influencés par des interactions multiples entre des facteurs physiques du milieu comme la bathymétrie, la topographie, la morphologie des îles, l'étendue des plateaux insulaires et la distance géographique, et sont associés à des variations hydrodynamiques à petite et grande échelles. L'objectif général de cette thèse est de définir et de modéliser le fonctionnement écologique de d'archipel du Cap-Vert en matière de structure et dynamique des populations démersales. Le travail considère l'échelle de l'île, du mois et de la saison. Il analyse les variables principales qui influencent …
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73.More information
RÉSUMÉ: La dégradation des écosystèmes marins et des ressources halieutiques se généralise. Défenseurs de l'environnement et gestionnaires des pêches s'entendent sur le constat d'échec des gouvernance et gestion actuelles, souvent déconnectées des volontés et des capacités locales. Ainsi, la gouvernance et la gestion marines ne peuvent plus faire abstraction du fait que leur objet est un socio-écosystème, et donc que le cadre humain, incluant les perceptions, influence les pratiques de gouvernance et de gestion à développer. L'île de Maio au Cap-Vert (Afrique de l’Ouest), dont la population dépend directement de l'océan pour sa subsistance, fait l'objet de projets visant à la fois la conservation marine, la pêche, et le développement touristique. Tous ces projets promeuvent la participation des communautés à la gouvernance et à la …
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74.More information
Statistics show that Africa's share of world manufacturing value added is only about 1.6% in 2014 (UNIDO, 2016). This weak industrial performance of the African continent is somewhat disappointing in view of the potential attraction of the investments it has. The purpose of this article is to identify the obstacles to Africa's industrial development. The argumentation developed is based both on the literature and on existing statistics. The article shows that the low level of infrastructure in African countries, especially the transport, telecommunications and energy infrastructure, is a major obstacle to the continent's industrial emergence. The lack of political vision, political instability, the small size of the market, the difficulties of access to finance, and the low level of human capital a real so highlighted as major obstacles to the industrialization of the continent.
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75.More information
To mark the fiftieth anniversary of the decolonization of Senegal, on 4 April 2010, twenty African heads of state proceeded to the inauguration of the “African renaissance” monument at Dakar. Previously symbolizing the memory of slavery and colonialism, the building of this memorial site with more questionable aesthetics and funding, and in a context of an economic slump occasioned lively disagreements of public opinion. The following article offers a textual analysis of the Senegalese press that, between 2008 and 2010, was at the centre of a lively controversy ranging from the symbolic meaning, to the cost and financing of this monumental work. Examining numerous newspaper articles, conversations and debates on broadcast radio, this article first questions the significance and the sense of commemoration that the Senegalese state wished to give the monument. The article then assesses the reasons why the symbolic and memorial representation of the concept of “African renaissance” did not work in the eyes of the public. It also sheds light on the religious, political and ethical foundations of this contested discourse.
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76.More information
Prima facie, the African continent does not appear to be largely implicated with illegal drugs. Transnational efforts to fight diverse type of trafficking in the world, as well as innovations and networks and processes exchange by traffickers groups led to a large impact on Africa's role as a transit point. International criminal groups take advantage of the region in relation to illegal trafficking. Globalisation allows for easier moving of people and products. The displacement of criminality in less policed areas but more corrupted is an important notion. Trafficking intensification seems to have the effect of enhancing drug consumption and abuse. In West Africa, poly use and international trafficking became a high concern for the international community. Cocaine and heroin exchange in West Africa became particularly dense and international trafficking organisations have worsened the situation. Moreover, trafficking has recently been extended from West Africa to East Africa. The last section is dedicated to the context and history of three different regions of Africa, in order to further our understanding of the actual problem. We examine the case of West Africa, East Africa and North Africa.
Keywords: Afrique, commerce illégal, mondialisation, trafic, consommation, drogue, Africa, illegal business, globalisation, traffic, drug abuse, África, comercio ilegal, mundialización, trafico, consumo, droga
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77.More information
The main interest of concentrations measurements of suspended sediment (SS) in a catchment area is to establish an average sediment budget and deduct mechanical erosion rates at the basin scale. However, quantification of SS yield of a river is a delicate task, particularly in semi-arid area where the violent floods and short duration make it difficult samples. In the present study, measurements of water discharge and concentrations has been conducted by the National Agency of Water Resources in Bou-Hanifia basin, an important sub-basin of the Macta watershed characterized by a semi arid climate and strong rates of erosion. The sediments budgets results reflect a very strong temporal variability, both at seasonal as interannual scale, of solid transport. This is largely related to the climate aggressivity that can provide a very strong mobilization of SS occurring at varying periods. At the watershed scale during the period 1993-2006, the average sediments budgets is estimated to be 1,8 x 106 tonnes (t) and a degradation of 343 t∙a-1∙km-2. Indeed, the wet years are more exporting of SS. Thus, autumn season is the most erosive of the year representing 75% of the annual budget. In fact, the majority of SS export occurs during flood at the end of summer and the beginning of autumn, and they are at the origin between 36% and 94% sediment yield annually transported for 1% of the time, or three days per year.
Keywords: Concentrations des matières en suspension, bassin versant, semi-aride, transport solide, crue, érosion, Concentration of suspended sediment, watershed, semi-arid, sediment transport, flood, erosion
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78.More information
The study is an analysis of the land cover spatial dynamics of the wetlands (Niayes) of Dakar from 1942 to 2014 by the use of geomatic tools. We used the aerial photographs of the years 1942, 1966 and 1978 and the satellite images of the years 2003 and 2014 to establish land-cover maps. The results of the analysis show that the big drought of the 1970s affected the hydrology of the Niayes and brought a decrease in the extent of the flood-prone areas. The surface of the latter varied from 35.84 % in 1942 to 5.44 % in 2003. From 2003, the increased urbanization of the area gradually reduced the area that used to be covered by the Niayes although flooded areas rose by 9.25% in 2014. At that time, the built-up area prevailed with 37.27% at the expense of bare areas, waters surfaces, and especially woodlands. The densification of the road network is the major driver of the fragmentation of the Niayes and the main entryway to their occupation.
Keywords: zone humide, « Niayes », cartographie, dynamique spatiale, occupation du sol, géomatique, Sénégal, wetlands, “Niayes”, cartography, spatial dynamics, land-cover, geomatics, Senegal
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79.More information
Corrosion features were observed on the South Shore of the Maritime St. Lawrence Estuary, in conglomerate, limestone, sandstone, shale and cristalline boulders, and are here described for the first time.An attempt to classify these minor features characteristic of rocky shores is made and an extensive bibliography is given.An effort should be made to get more information on the geographical distribution of coastal corrosion forms on non calcareous rocks in cold regions.
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80.More information
The pattern of rocky shorelines in eastern and southeastern fjords of Iceland, between Reydarfjördur and Álftafjördur (exposed or sheltered places), is examined. Faults are very scanty and have no effect upon the general trends of the coastline. Small parallel asymmetric rocky headlands are numerous. Differential marine erosion is the main factor. Thick flood basalts have a western dip (6° to 10° at sea level) and the strandflat cuts across the strata. The headlands correspond to the strongest and thickest flows: olivine tholeiites, tholeiites and feldspar-porphyritic basalts. Notches, overhangs and sea caves develop in weak rocks (propylitised basalts, basalts with abundant amygdale minerals, reddish tuffaceous material between the flows,...). Differences in dyke erosion occur. Some dykes give prominent ridges or walls; others are excavated, specially the composite dykes (thin basaltic margins and thick rhyolitic cores). Transverse, oblique and longitudinal types of structural coastlines are distinguished.