Abstract:
The proliferation of woody species alters the vegetation structure, leading to
loss of rangeland productivity. It aimed to assess the influence of tree density
on vegetation and soil chemical properties at three levels of encroachment;
open, moderate and dense. Each level of encroachment was replicated 3
times, a 5000 m2 plot was marked per replicate. Four belt transects 200 m2
were placed per plot. Woody species within each belt transect per replicate
were identified and recorded to evaluate woody species composition. Grass
species composition was assessed using a step point method. Soil was sampled
per replicate and analysed for chemical properties. Results showed that
71% of grasses were increasers and 29% decreasers. Digitaria eriantha and
Eragrostis obtusa were the most dominant species. Vachellia karoo and Aloe
ferox were the most dominant woody species. The dense had high nitrogen
(1.48%) compared to the moderate (0.23%) and the open (0.17%). Increaser
species, soil carbon, soil pH increased with the increase of tree density. It was
concluded that the replacement of highly palatable grasses with inferior ones
was due to improper rangeland management practices. It was recommended
that land users form rangeland management associations and set up conservation
agreements for proper management of resources.
