WOODY VEGETATION DIVERSITY AND REGENERATION IN AN ABANDONED SUGAR ESTATE IN SEMI-ARID ZIMBABWE - T. N. Gotosa; J. Gotosa; C. A. T. Katsvanga; I. W. Nyakudya A. Kundhlande; I. Mapaure (Journal of Animal and Plant Sciences, 2013)
This study assessed woody species diversity and regeneration, 30 years after cessation of sugar cane production in Chirundu Estate situated in the Zambezi river valley floor of Zimbabwe. Nineteen plots were studied to compare woody vegetation in the undisturbed and disturbed areas. The undisturbed area had 42 species and exhibited greater (p<0.05) woody vegetation species diversity than the disturbed area with 19 species. Cultivation converted a Combretum mossambicensis dominated thicket to a Dichrostachys cinerea thicket. Six vegetation subtypes were separated by the Hierarchical Cluster Analysis of species richness data whilst the Detrended Correspondence Analysis identified three groups. Cultivation was accountable for 50% variation in vegetation species composition.Vegetation regeneration in the undisturbed area as measured by the sapling-to-tree ratio (STR) was low (mean STR=0.444(0.309)) and medium (mean STR=0.630(0.517)) in the disturbed area but were not significantly (p>0.05) different. It was concluded that vegetation in the disturbed area was still in early stages of succession and the co-existence of early and late succession species indicated some degree of disequilibrium dynamics whilst high herbivory and arid conditions of the estate were attributable to the retarded rate of woody vegetation succession.
Keywords: journal article; species richness; succession; disturbance; herbivory; disequilibrium