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  • A late holocène (c. 4500-2300 BP) climatic chronology for the southwestern Sahara in Palaeoecology of Africa and the surrounding islands-Vol 13.
  • Faunal and floral remains, changing lake levels, and a series of 15 radiocarbon dates from south-central Mauritania document climatic changes in the period c. 4500 to 2300 BP and provide the basis for estimation of mean annual precipitation greater
  • than 300 % of present before 4500 BP, decrease to less than 200 % in the period 4500-3500 BP, increase to greater than 200 % at 3500 BP, and then a gradual decrease to c. 175 % by 2900 BP and to c. 150 % by 2300 BP.
  • of elliptical mound might result from the decay of mud constructions| 3. the disappearance of arboreal pollen from spectra in the upper part of the diagram is related to human activity, which is dated c. 1000 AD.
  • FELLER, C.
  • PAYCHENG, C.
  • : peak elevations Ras Dejen 4543 m). Thus, the most likely palaeoclimate was about 7 C cooler, and poor in run off and rainfall. It had a tendency towards winter precipitation and only occasional summer cloud cover, without monsoon activity, and remained