Creator: Strohbach, Ben J. Citation: Namibian Journal of Environment 2017 Vol 1. Section A: 19-42 URL: http://www.nje.org.na/index.php/nje/article/view/volume1_p19-42_strobach Date: 2017 Language: English Subjects: Auas Mountains; freehold conservancies; Highland Savannah; Khomas Hochland; phytosociology; vegetation classification Coverage: Namibia Abstract: The Auas-Oanob Conservancy is situated in the very rugged, botanically highly diverse Khomas Hochland in central Namibia. A number of vegetation-related studies have been undertaken in this highland before, but none covering the full extent of the conservancy, and with different interpretations of the syntaxonomy of the vegetation. The current study aimed to describe and map the vegetation of the conservancy for practical management purposes. A total of 229 relevés was compiled within the conservancy, and 72 relevés from other studies (falling either within the conservancy, or the nearby Auas Mountain range) were added. The data were classified with a Modified TWINSPAN. Three large groups were identified: (a) the high-altitude veld of the Auas Mountain range, with three associations being recognised on the basis of altitude and aspect; (b) the lowlands and valley veld with five associations, and (c) the Khomas Hochland veld with five associations. These 13 associations are described, mapped and compared to descriptions of the vegetation in the vicinity of the conservancy. A higher-order syntaxonomy, with three orders, one subdivided into two alliances, is suggested. This higher-order syntaxonomy needs to be further investigated, taking into account vegetation descriptions of the greater Khomas Hochland. The high-altitude veld of the Auas Mountain range has a unique composition with a high degree of endemisim and a sub-alpine character. Due to its restricted range, there is an urgent need for formal protection. Two associations within the lowland and valley veld are under threat, being the Platycarphella carlinoides - Chloris virgata association of the omiramba (erosion) and the Schmidtia kalahariensis - Acacia erioloba association in the bottom lands at Omeya (development). Bush encroachment is a general threat to various upland associations. |
Vegetation of the Auas-Oanob Conservancy in the Khomas Hochland of Namibia