The investigations were conducted on three sites along the BIOTA Southern Africa transect and were part of an integrated research approach. The BIOTA transect ranges basically in north-south direction from the Kavango in the Republic of Namibia to the Cape in the Republic of South Africa, covering a broad range of rainfall regimes as well as different geological and topographical units. In addition, it comprises two minor transects in east-west orientation from the coast to central parts of Namibia. Along those transects, 35 standardised long-term monitoring sites, so-called biodiversity observatories, were established, each 1 x 1 km in size, subdivided into a one hundred hectare plots. Most of the observatories have been established during Phase I of the BIOTA project (2000 - 2003); since then, researchers of various disciplines conducted their investigations, following standardised scales and methods, which led to a dense and interdisciplinary highly comparable data base which was available for this study. The examinations are supplemented by data from climate stations that had been established on 18 observatories.