Cette recherche se limite aux régions du Darfour et du Kordofan te tente de faire un état de la question à partir des quelques rapports de fouilles publiés et de l'analyse des objets conservés dans les réserves des musées soudanais. Cette partie du Soudan manque de recherches et de travaux archéologiques, une grande partie vide dans l'histoire couverte par plusieurs siècles. L'étude des sites et des objets a été réalisée sur plusieurs plans : étude chronologique, analyse des productions et de leur évolution technique, distribution du matériel, identification des occupations humaines. Le cadre chronologique pris en compte dans notre étude s'étend du paléolithique jusqu'aux périodes islamiques, et porte sur les sites archéologiques et le matériel. Selon cette étude, les deux régions montrent des cultures très riches et de développement différent et parallèle à celui de la vallée du Nil dans presque toutes les périodes historiques. L'objectif de cette recherche est donc de faire le point sur, et de compléter nos connaissances sur l'antiquité et l'histoire ancienne du Darfour et du Nord Kordofan, qui pourront être utiles pour des travaux futurs / This search is limited to areas of Darfur and Kordofan and tries to make a state of affairs from the few published reports of excavations and analysis of objects preserved in the museum storage Sudan. This part of Sudan is lack of research and archaeological work, a largely empty in the history covered by several centuries. The study of these sites and objects has been done in several ways : chronological study, analysis of production and their technical evolution, distribution of materials, identification of human occupations. The limit time considered in this study extends from the Paleotlthic to the Islamic period, and focuses on the archaeological sites and materials, according to this, the two regions show rich cultures and different development which parallel to the Nile Valley in almost all historical periods. The objective of this research is to shed a light to the antiquity and ancient history of Darfur and North Kordofan, which will be useful for future work

Although Sudan is a country with enormous agricultural potential, agriculture has not prospered over the last two decades and Sudan now finds itself a bankrupt net importer of food. Much of the country's agricultural resource base is found in the rainfed agricultural region of Western Sudan, which includes Kordofan. This study focuses on Kordofan, and reports on data gathered during work for the Western Sudan Agricultural Research Project. Rather than following the production orientation usually employed by economists, it addresses issues related to the role of marketing in agricultural economic development. Marketing in Kordofan, as well as production, is subject to disruption because of climatic variations characteristic of arid and semi-arid regions. Extended annual dry periods and droughts distort price performance for agricultural commodities and cause shifts in marketing channel structure. Risk levels are substantially increased for producers and small traders, while at the same time they must take on increased responsibility for many channel functions. Marketing also suffers from infrastructure deficiencies: roads are often impassable during the rainy season, and storage losses become huge over the course of a year. The private marketing system in Kordofan has adapted to these conditions, and is performing quite effectively, efficiently, and equitably, given the adverse conditions. Competition is extensive, farmers have many alternatives when selling crops, and merchants operate on fairly modest profit margins. A widespread bias against the private sector has led to extensive government intervention into marketing spheres. These policies include direct operation of some marketing channels, manipulation of price structures through artificial exchange rates and price controls, and restrictive licensing practices. Wherever such policies have been applied in Kordofan, they have led to declining production of government controlled crops, they have restricted competition in marketing channels, and they have lowered living standards for producers and consumers. Sudan has not successfully identified areas where private channels in Kordofan cannot solve problems, and which therefore require public intervention. The government seems to have based its economic decisions upon ideological considerations and intervened in areas which it cannot perform as well as the private market.

Diss.--Bayreuth, 1999. / Bibliogr. p. 387-406.

Zugl.: Dresden, Techn. Univ., Diss., 2007

Techn. Universiẗat, Diss., 1998--Berlin.

Cette étude concerne la région du Kordofan, au centre-Sud du Soudan. La région étudiée est comprise entre les méridiens 28° 00' et 31° 00' E, et les latitudes 11° 30' et 15°00' N, et couvre une surface d’environ 125 835 km2. Le Kordofan est situé en bordure Sud du Sahara actuel. Les dépôts du Pléistocène supérieur-Holocène du Kordofan, ont enregistré des discontinuités sédimentaires qui reflètent des fluctuations climatiques au cours du Quaternaire terminal. Des datations au 14C et des collectes archéologiques ont permis de dater la série étudiée. Quatre unités stratigraphiques ont été identifiées, qui comprennent huit faciès sédimentaires.La première unité est antérieure à ≈ 10 ka BP et est formée de grès ou siltstone marmorisés d’origine éolienne. La deuxième unité (≈ 10 à 6 ka BP) comprend des faciès palustres et lacustres au Nord et au centre, et des faciès fluviatiles au Sud. La troisième unité, d’âge ≈ 6 à 3 ka BP, n’est présente qu’au Sud; elle est faite de dépôts éoliens intercalés de faciès fluviatiles ou de plaine d’inondation. La quatrième unité est plus jeune que 1000 ans BP, et est dominée par des grès rouges éoliens au Nord, et par des dépôts de plaine d’inondation au Sud. Entre ≈ 6 et 1 ka BP au Nord et entre ≈ 3 et 1 ka BP au Sud, un hiatus est marqué par une surface de déflation au North, et est interprété comme une période de forte activité éolienne, qui a empêché le dépôt et a même érodé une partie des sédiments déposés entre 6 et 3 ka BP.Plusieurs proxys (sédimentologie, gastéropodes, pollens, isotopes stables, géochimie des majeurs, minéralogie des argiles et paléo-hydrologie) ont servi à reconstituer l’évolution climatique de la région depuis 13000 ans, qui est cohérente avec l’évolution paléo-climatique de l’Afrique nord-orientale à la même époque. Nos résultats montrent que la région a connu un climat aride avant 10 ka BP, matérialisé par d’épais dépôts éoliens. Entre 10 et 6 ka BP, un climat humide est démontré par le développement de nodules calcaires pédogénétiques, le dépôt local de calcaires palustres et lacustres, l’abondance de gastéropodes aquatiques et semi-aquatiques, le haut niveau de lacs, et les valeurs très négatives du δ18O des coquilles d’escargots et des nodules calcaires. Après ≈ 6 ka BP, le climat s’assèche dans le Nord de la région étudiée comme le suggèrent la forte activité éolienne enregistrée par un hiatus sédimentaire, des érosions et surfaces de déflation, alors que le Sud reste plus humide, comme le montrent des dépôts fluviatiles (chenaux et plaine d’inondation), et les pollens tropicaux et aquatiques. Après 1000 ans BP, et plus probablement après 3 ka BP, la région devient aride comme en témoignent les dépôts éoliens, la prédominance de pollens de milieu aride et l’enrichissement en 18O des coquilles d’escargots terrestres. / This study is conducted in the Kordofan region, central-southern Sudan. The study area is bounded by longitudes 28° 00' and 31° 00' E, and latitudes 11° 30' and 15°00' N and covers an area of about 125835 km2. The Kordofan region is located at the southern end of the present-day Sahara. Late Pleistocene-Holocene deposits in Kordofan, recorded sedimentary discontinuities that probably reflect climatic fluctuations during the latest Quaternary. 14C dating and some archeological findings have been used to date the latest Pleistocene-Holocene succession. In the investigated sections, four stratigraphic units have been recognized, which exhibit eight sedimentological facies.The first unit is older that ≈ 10 ky BP and is formed of mottled sandstone or siltstone facies of aeolian origin. The second unit (≈ 10 to 6 ky BP) comprises palustrine and lacustrine facies in the central and northern parts, and fluviatile facies in the South. The third unit ranges from ≈ 6 to 3 ky BP and is restricted to the southern part; it is made of aoelian deposits intercalated with fluviatile or flood plain facies. The fourth unit is younger than 1000 y BP, and is dominated by aeolian red sandstone in the North, and by flood plain facies to the South. Between ≈ 6 and 1 ky BP in the North and between ≈ 3 and 1 ky BP in the South, no deposits are recorded. This hiatus is marked by deflation surfaces in the North, and is interpreted as a period of strong aeolian activity, which prevented deposition, or even eroded part of the sediments deposited between 6 and 3 ky BP.Several proxies (sedimentology, gastropod sub-fossil shells, pollens, stable isotopes, major element chemistry, clay mineralogy and paleohydrology) have been used to reconstruct the climatic evolution of the region for the past 13 ky, which can be correlated to the well-known evolution of Eastern Sahara during this time-span. Our results indicate that the region has been subjected to arid climate prior to 10 ky BP as evidenced by thick aeolian deposits. Between 10 and 6 ky BP, the region experienced a wet climate as evidenced by the development of pedogenetic calcareous nodules, local deposition of palustrine and lacustrine limestone, abundance of aquatic and semi-aquatic gastropods, high lake levels, and depleted δ18O values from gastropod shells and calcareous nodules. After ≈ 6 ky BP, climate evolved to dry conditions in the northern part of the region as indicated by an strong aeolian activity recorded by erosion features, sedimentary hiatus and deflation surfaces, while its southern part remained more humid, as shown by channel and flood plain deposits, and tropical and aquatic pollen taxa. From 1000 yr BP to Present, and probably after 3 ka BP, the region became arid as evidenced by aeolian deposits, the predominance of arid indicator pollens and the enrichment in 18O of land snail shells.

Zugl.: Giessen, Univ., Diss., 2008

Zugl.: Giessen, Univ., Diss., 2008

The gum arabic belt in Sudan plays a significant role in environmental, social and economical aspects. The belt has suffered from deforestation and degradation due to natural hazards and human activities. This research was conducted in North Kordofan State, which is affected by modifications in conditions and composition of vegetation cover trends in the gum arabic belt as in the rest of the Sahelian Sudan zone. The application of remote sensing, geographical information system and satellites imageries with multi-temporal and spatial analysis of land use land cover provides the land managers with current and improved data for the purposes of effective management of natural resources in the gum arabic belt. This research investigated the possibility of identification, monitoring and mapping of the land use land cover changes and dynamics in the gum arabic belt during the last 35 years. Also a newly approach of object-based classification was applied for image classification. Additionally, the study elaborated the integration of conventional forest inventory with satellite imagery for Acacia senegal stands. The study used imageries from different satellites (Landsat and ASTER) and multi-temporal dates (MSS 1972, TM 1985, ETM+ 1999 and ASTER 2007) acquired in dry season (November). The imageries were geo-referenced and radiometrically corrected by using ENVI-FLAASH software. Image classification (pixel-based and object-based), post-classification change detection, 2x2 and 3x3 pixel windows and accuracy assessment were applied. A total of 47 field samples were inventoried for Acacia senegal tree’s variables in Elhemmaria forest. Three areas were selected and distributed along the gum arabic belt. Regression method analysis was applied to study the relationship between forest attributes and the ASTER imagery. Application of multi-temporal remote sensing data in gum arabic belt demonstrated successfully the identification and mapping of land use land cover into five main classes. Also NDVI categorisation provided a consistent method for land use land cover stratification and mapping. Forest dominated by Acacia senegal class was separated covering an area of 21% and 24% in the year 2007 for areas A and B, respectively. The land use land cover structure in the gum arabic belt has obvious changes and reciprocal conversions between the classes indicating the trends and conditions caused by the human interventions as well as ecological impacts on Acacia senegal trees. The study revealed a drastic loss of Acacia senegal cover by 25% during the period of 1972 to 2007.The results of the study revealed to a significant correlation (p ≤ 0.05) between the ASTER bands (VNIR) and vegetation indices (NDVI, SAVI, RVI) with stand density, volume, crown area and basal area of Acacia senegal trees. The derived 2x2 and 3x3 pixel windows methods successfully extracted the spectral reflectance of Acacia senegal trees from ASTER imagery. Four equations were developed and could be widely used and applied for monitoring the stand density, volume, basal area and crown area of Acacia senegal trees in the gum arabic belt considering the similarity between the selected areas. The pixel-based approach performed slightly better than the object-based approach in land use land cover classification in the gum arabic belt. The study come out with some valuable recommendations and comments which could contribute positively in using remotely sensed imagery and GIS techniques to explore management tools of Acacia senegal stands in order to maintain the tree component in the farming and the land use systems in the gum arabic belt.

Sudan as a Sahelian country faced numerous drought periods resulting in famine and mass immigration. Spatial data on dynamics of land use and land cover is scarce and/or almost nonexistent. The study area in the North Kordofan State is located in the centre of Sudan and falls in the Sahelian eco-climatic zone. The region generally yields reasonable harvests of rainfed crops and the grasslands supports plenty of livestock. But any attempts to develop medium- to longterm strategies of sustainable land management have been hampered by the impacts of drought and desertification over a long period of time. This study aims to determine and analyse the dynamics of change of land use/land cover classes. The study attempts also to improve classification accuracy by using different data transformation methods like PCA, TCA and CA. In addition it tries to investigate the most reliable methods of pre-classification and/or post-classification change detection. The research also attempts to assess the desertification process using vegetation cover as an indicator. Preliminary mapping of major soil types is also an objective of this study. Landsat data of MSS 187/51 acquired on 01.01.1973 and ETM+ 174/51 acquired on 16.01.2001 were used. Visual interpretation in addition to digital image processing was applied to process the imagery for determining land use/land cover classes for the recent and reference image. Pre- and post-classification change detection methods were used to detect changes in land use/land cover classes in the study area. Pre-classification methods include image differencing, PC and Change Vector Analysis. Georeferenced soil samples were analysed to measure physical and chemical parameters. The measured values of these soil properties were integrated with the results of land use/ land cover classification. The major LULC classes present in the study area are forest, farm on sand, farm on clay, fallow on sand, fallow on clay, woodyland, mixed woodland, grassland, burnt/wetland and natural water bodies. Farming on sandy and clay soils constitute the major land use in the area, while mixed woodland constitutes the major land cover. Classification accuracy is improved by adopting data transformation by PCA, TCA and CA. Pre-classification change detection methods show indistinct and sketchy patterns of change but post-classification method shows obvious and detailed results. Vegetation cover changes were illustrated by use of NDVI. In addition preliminary soil mapping by using mineral indices was done based on ETM+ imagery. Distinct patterns of clay, gardud and sand areas could be classified. Remote sensing methods used in this study prove a high potential to classify land use/land cover as well as soil classes. Moreover the remote sensing methods used confirm efficiency for detecting changes in LULC classes and vegetation cover during the addressed period.