Show simple item record A. -. M. en_US M. en_US R. en_US Henry F. en_US 2008-12-15T16:41:01Z 2008-12-15T16:41:01Z 2007-09 en_US
dc.identifier en_US
dc.identifier.citation Lezine , A M , Umer , M , Bonnefille , R & Lamb , H F 2007 , ' Late pleistocene and holocene vegetation history of the Bale mountains, Ethiopia ' Quaternary Science Reviews , vol 26 , no. 17-18 , pp. 2229-2246 . , 10.1016/j.quascirev.2007.05.004 en_US
dc.identifier.other PURE: 94751 en_US
dc.identifier.other dspace: 2160/1663 en_US
dc.description.abstract A sediment core recovered from Garba Guracha, a glacial lake at 3950 m altitude in the Bale Mountains of Ethiopia, at the boundary of the Ericaceous and Afroalpine vegetation belts, provides a 16,700-year pollen record of vegetation response to climatic change. The earliest vegetation recorded was sparse and composed mainly of grasses, Amaranthaceae–Chenopodiaceae and Artemisia, indicating an arid climate. At 13,400 cal BP, Amaranthaceae–Chenopodiaceae pollen declined sharply and Cyperaceae increased, suggesting a change to moister conditions. The Younger Dryas interval is represented by a small increase in Artemisia and reduced Cyperaceae, indicating aridity. Just after the start of the Holocene (11,200 cal BP), the upper altitudinal limit of the Ericaceous belt rose, and woody Ericaceous vegetation extended across the Sanetti plateau, in response to increased moisture and temperature. The marked change from clastic to organic lake sedimentation at this time reflects the increase in woody vegetation cover in the lake catchment, accompanied by soil stabilisation, and increased leaf litter and soil humus content. From about 6000 cal BP, and especially after 4500 cal BP, mid-altitude dry Afromontane Juniper–Podocarpus forests developed on the northern slopes of the mountains in response to reduced rainfall in a shortened wet season. Erica shrub and forest decreased in area and altitude, and the Afroalpine ecosystem expanded on the plateau. Podocarpus declined from about 2000 cal BP, as Juniperus increased to its present dominance at 2500–3300 m altitude. Human impact on the high-altitude Afroalpine and Ericaceous vegetation has been relatively minor, confirming that the endemic biodiversity of the Ethiopian mountains is a legacy of natural Holocene vegetation change, following repeated expansion and contraction of the upland ecosystems during the Quaternary. en_US
dc.format.extent 18 en_US
dc.relation.ispartof Quaternary Science Reviews en_US
dc.title Late pleistocene and holocene vegetation history of the Bale mountains, Ethiopia en_US
dc.contributor.pbl Institute of Geography & Earth Sciences en_US
dc.contributor.pbl Quaternary Environmental Change Group en_US

Files in this item

Files Size Format View

There are no files associated with this item.

This item appears in the following Collection(s)

Show simple item record

Search Cadair

Advanced Search