The historical ecology of Namibian rangelands: Vegetation change since 1876 in response to local and global drivers

摘要: Abstract The influence of both local and global drivers on long-term changes in the vegetation Namibia's extensive rangelands was investigated. Fifty-two historical photographs Palgrave Expedition 1876 were re-photographed used to document over more than 130 years, grass, shrub tree cover within three major biomes along a 1200 km climatic gradient central southern Namibia. We showed that patterns change are correlated with mean annual precipitation (MAP) below threshold around 250 mm, has remained remarkably stable regardless land-use or tenure regime. Above this threshold, an increase is linked rainfall gradient, legacies events late 19th century, subsequent transformations increased atmospheric CO 2 . discuss these findings relation pastoral settler societies, paleo- trends predictions under future warming scenarios. argue associated colonialism (decimation megaherbivores wildlife browsers; fire suppression, cattle ranching), as well effects fertilisation provide most parsimonious explanations for change. found no evidence aridification, projected climate scenarios, started region. This study provided empirical theoretical insights into relative importance savanna environments Namibia ecosystems generally.