Ibouhouten H.,Moulay Ismaï University |
Ibouhouten H.,University dOsnabrilck |
Zielhofer C.,Departement de Geographie |
Zielhofer C.,University dOsnabrilck |
And 13 more authors.
Geomorphologie: Relief, Processus, Environnement | Year: 2010
The Lower Moulouya Basin in northeast Morocco is characterised by Mediterranean arid to semiarid environmental conditions of a North African desert margin. In geomorphological research, desert margins reveal a high potential for palaeoenvironmental studies, as they react very sensitive to past and future climatic changes. The alluvial deposits of the Lower Moulouya can be divided in three sedimentation series: the Series I is dated between 9.9 and 65 ka cal. BP and shows silty to sandy layers with hydromorphic features and intercalated initial alluvial soils. The Series II is dated between 4.2 and 3.2 ka cal. BP and indicates clayey to silty fine laminae with hydromorphic features and an onset of charcoal-rich layers. The Series III is dated between 3.2 and 1.4 ka cal. BP and features clayey to silty fine laminae with greyish to reddish colouring. Series III reveals charcoal-rich layers and gypsum crystals in clay-rich reddish sediments. The dating of the archaeological findings (silex, ceramics, bones) of the buried open air sites indicate an human occupation at the Lower Moulouya during the Epipalaeolithics, Neolithics, Protohistoric and Middle Ages. The phases correspond chronologically with already known archaeological archives from eastern Rif rock-shelters and caves. The maximum of archaeological findings at the Lower Moulouya corresponds to the Early Neolithics, a period which comes along with the Mid-Holocene climatic optimum.
Bahir M.,Cadi Ayyad University |
Moukhayar R.E.,Cadi Ayyad University |
Chamchati H.,Cadi Ayyad University |
Youbi N.,Cadi Ayyad University |
And 3 more authors.
Comunicacoes Geologicas | Year: 2014
Arid and semi-arid areas are threatened by desertification, and thus the degradation due to various factors, including drought, of course, but also the exploitation of resources. They are, in fact, already in a state of stress (resources less than 500 m3 per year per capita) with important disorders induced by climate change. These make an impact on the hydrological cycle, with longer droughts and increased flooding. These disorders will strengthen the already observed degradation of ecosystems, which are often overexploited. Essaouira synclinal area is part of the semi-arid areas of Morocco that are subject to the impact of climatic and human pressures. In the case of this coastal area, which includes two main aquifers superimposed; the Plio-Quaternary and Turonian, the resulting vulnerability is compounded by the risk of infiltration navy. The Rainfall in the area does not exceed 300 mm year-1, the average temperature hovers around 20°C, the piezometric map of Essaouira synclinal basin was made, different water samples have been collected from October 2009 after exceptional rainfall, all waters are sodium-chloride facies, interpretation of mineralization indicates power by the Ksob Wadi in the northeast and increasing levels of chlorides in the central part generated by the Essaouira diaper hidden. Excessive levels of nitrates have been identified, as well as chlorides after rains of winter 2009. The electrical conductivity and concentrations of 18O and 2H were measured, a local meteoric water line was determined according to the Atlantic origin of precipitation. However, the water Turonian, characterized by significant resources, demonstrates a very low charging current; its vulnerability would be more related to human pressure than changes in climatic conditions. Keywords: Basin of Essaouira, Aquifer, Semi-arid regions, Drought, Hydro geochemistry, Stable isotopes, Recharge. © 2014, LNEG – Laboratório Nacional de Geologia e Energia IP.
Ghilardi M.,French National Center for Scientific Research |
Cordier S.,University Paris Est Creteil |
Carozza J.-M.,Departement de Geographie |
Psomiadis D.,French National Center for Scientific Research |
And 8 more authors.
Environmental Archaeology | Year: 2015
This study aims to reconstruct the Holocene fluvial history of the Tremithos river, south central Cyprus and examine linkages to regional and local archaeological records. Three stratigraphic profiles (Sp1, Sp2 and Sp3) located in the lower valley have been investigated using sedimentology and magnetic parameters. The14C dating of 10 samples reveals mid-Holocene ages for Sp1 and Sp2, while the upper most part of Sp3 can be attributed to the early to mid-Holocene. Two main phases of vertical accretion have been recognised: the first, recorded in the lower most part of Sp3, could not be dated but might relate to the late Glacial period. It is not associated with any archaeological artefacts. The second, recorded in all profiles, dating from ca. 5000 to ca. cal 2800 BC, spans the Late Neolithic Sotira (cal 4800/4000 BC) and Late Chalcolithic (cal 2900–2500 BC) cultures. The sediments of Sp1 and Sp2 are up to 8–10 m thick and mainly composed of fine material. However, an intercalated phase of coarse sediment has been identified at the beginning of the third millennium BC, indicating a sudden change in river dynamics, potentially associated with the 5.2 ka rapid climate change regional event. Typical mid-Chalcolithic (ca. cal 3300–3050 BC) ceramics found in a palaeosol in Sp2 indicate for the first time human occupation of the Tremithos river terraces. Two other palaeosols have also been recognised in Sp3 and radiocarbon dated to ca. cal 5600–4100 BC and ca. cal 2900–2600 BC, respectively. These results make it possible to propose a palaeogeographic reconstruction of the Holocene evolution in the Tremithos valley and to make a preliminary assessment of the relative roles of tectonics, climate and anthropogenic forcing. © Association for Environmental Archaeology 2015.
Niang-Diene A.,Cheikh Anta Diop University |
Salem G.,Departement de geographie
Bulletin de la Societe de Pathologie Exotique | Year: 2015
In Senegal, the evolution of disease as recorded by the public health care system confirms the preponderance of seeking care for infectious diseases (malaria, respiratory and diarrheal diseases) and reveals the emergence of chronic diseases. However, while the incidence of hypertension diagnosed by the public system increased from 14 to 81 per thousand inhabitants aged over 40, between 1995 and 2009, the diabetes appears only at 0.4‰, thus in contradiction with hospital data and general population surveys. For instance, diabetes prevalence was estimated at 10.4% in Saint-Louis in 2010 (8). This difference recalls the limitations of this data source as regards epidemiological information, but sheds light on the challenges facing the health care system, both in terms of detection, medical care, access to health care and treatment as well as cost recovery. © 2014, Springer-Verlag France.