Rare plants in a Succulent – Nama Karoo ecotone in southern Africa

摘要: Phylogenetic patterns, adaptations and conservation status of the rare species flora a winter–summer rainfall ecotone in southern Africa were investigated to shed light on species' evolutionary history requirements. Some 11% (93 species) Greater Fish River Canyon Landscape Namibia classified as species, more than half currently not receiving formal protection Namibia. The does present subset overall pool, but unique assemblage plant over-represented by members family Mesembryanthemaceae, Crassulaceae, Asphodelaceae Hyacinthaceae. Low growth forms (dwarf leaf-succulent shrubs, dwarf stem succulents deciduous shrubs) well bulbs are common amongst species. Multiple factors processes, likely interlinked, believed be responsible for determining flora, indicating that individual respond differently challenges posed this arid environment. plants remnants wetter conditions past, which have retained viable populations mountainous terrain landscape, others may evolved situ. Resume Les schemas phylogenetiques, les et le statut de des especes vegetales rares d'un chutes pluie hiver-ete en Afrique australe ont ete etudies afin faire la lumiere sur l'histoire l'evolution exigences leur conservation. Quelque (93) du Paysage Namibie classees comme plus moitie ne recoivent actuellement aucune officielle dans ce pays. La flore ces represente pas un sous-ensemble pool total mais d'especes ou membres familles Hyacinthaceae sont surrepresentes. Les formes croissance lente (buissons feuilles naines, succulentes tiges buissons nains decidus) ainsi que bulbes frequents parmi rares. On pense facteurs processus multiples, probablement interconnectes, responsables determination rares, qui indique chaque espece repond differemment aux defis poses par cet environnement aride. Certains plantes vestiges anciennes humides preserve viables parties montagneuses paysage d'autres pourraient avoir evolue situ.