Vegetation Dynamics of Sloping Lands under Different Grazing Pressures in the Highlands of Ethiopia

Abstract

The impact of livestock grazing on the dynamics of vegetation species in the highland slopes of Ethiopian was studied. This was done by analyzing vegetation species germinating from cattle dung collected from the slopes at different times and comparing these species with those found on the pastures the animals regularly grazed. It was observed that grazing had little effect on the species richness of pastures above 3% slope while moderate and heavy grazing increased bio-diversity of pastures found on 2-3% slopes. However, heavy grazing pressure resulted in good grazing ever, heavy grazing pressure resulted in good grazing quality species being replaced by poor quality species. The effect of grazing on vegetation dynamics of the pastures was complicated by the fact that cow dung was often collected for fuel, and that at certain times, animals moved to higher slopes outside the study area. Further research is needed to determine where the animals go and what type of vegetation species they graze whenever they leave to confines of the pastures studied here, and to ascertain the dormancy and viability of the seeds of the various vegetation species when they pass through the rumens of the animals in order to get a clearer picture on the effects of grazing on vegetation dynamics.

UNISWA Research Journal of Agriculture, Science and Technology Vol. 4 (1) 2000: pp 44-54