dc.description.abstract | The object of this study was to investigate the effects of burning,
grazing and habitat on species composition, nutritional quality of
the grasses, and the vegetation and grazing herbivore biomass.
Comparisons of the above variables were made between burnt and
lightly grazed plots inside the park and heavily grazed areas
outside. Comparisons of quality between the treatments showed that
quality was highest in the burnt areas, followed by heavily grazed
and was lowest in the lightly grazed areas.
Species composition varied between the treatments. Pennisetum
mezianum, a coarse and unpreferred species and Eragrostis
tenuifolia, a species which has been suggested as being highly
successful in heavily grazed areas were abundant. Early burning
affected species composition by changing the relative contribution
of the different species to the total biomass. In some habitats, .- certain forbs were eliminated by burning. Biomass quickly increased
to amounts found before burning except where grazing pressure was
high. Outside the park, where there was heavy and continuous
grazing, biomass remained low, but quality was sufficiently high.
Animal counts at two-week intervals showed that animals
particularly grazing herbivores preferred the burnt areas where the
nutritional quality was high. Most animals moved out of the burned
areas when grasses became tall and f1l1alitydeclined.
Results of the controlled experiments showed that heavy
simulated grazing reduced total production of the plant. There was no significant difference between no grazing
though the results showed a slight stimulation peak at moderate levels of grazing. | en |