Sentences with phrase «aridity gradients»

Spatial patterns of loss and gain showed contrasting latitudinal patterns, with a westward range shift of species around the species - rich equatorial transition zone in central Africa, and an eastward shift in southern Africa; shifts which appear to be related mainly to the latitudinal aridity gradients across these ecological transition zones

Rainfall change and variability is very likely to affect vegetation in tropical grassland and savanna systems with, for example, a reduction in cover and productivity simulated along an aridity gradient in southern African savanna in response to the observed drying trend of about 8 mm / yr since 1970 (Woodward and Lomas, 2004a).