Cross-border studies offer unique situations to study the
impact of different land-use regimes on ecosystems. Along
the Angolan and Namibian border formed by the Okavango
River, the environmental conditions and traditional
land-use practises are the same on either side of the river.
However, decades of civil war in Angola led to a stagnant
development while political stability in Namibia fostered a
recent socio-economic transformation. We investigated the
impact of spatially diffuse land use on plant diversity of the
dry tropical woodlands covering the vast, sandy hinterlands
of the river. As accessibility is the major factor
governing land use, we used distance to road as a proxy for
land-use intensity. Based on 58 vegetation plots sized
20 m 9 50 m, we showed that species richness increased
with distance to road in Angola while in Namibia it
remained constant on a lower level. Evenness showed an
inverse pattern to species richness and Shannon diversity
index showed no response. Analysing diversity patterns
according to life forms revealed that these patterns are
primarily driven by woody species. The study showed that
spatially diffuse land use has a measurable effect on plant
diversity and illustrates that roads act as vectors of change.