Short-Term Influence of Fire on Herbaceous Composition, Diversity and Grass Biomass Production in Semi-Arid Savanna Woodland in Windhoek, Namibia

A comparative study on short term influence of fire on herbaceous composition and grass biomass production was conducted in a semi-arid savanna woodland in Windhoek, to assess differences in herbaceous composition and grass biomass production after a late dry season fire. The study revealed that herbaceous composition and grass cover differ significantly between the burned and unburned areas. Grass cover differed significantly (p< 0.001) between the burned and unburned areas. Fire removes aging grass materials, growth inhibitors and moribund hence, enhancing the vitality grasses. There were no significant differences in species richness (t = -1.402, p > 0.05), species diversity (t = -1.391, df = 28, p > 0.05), grass biomass production (t = 1.724, p > 0.05) and forb densities (t = 0.361, p > 0.05) between the burned and unburned areas..The study findings suggested that short term fire does have a significant impact on grass cover and herbaceous dominance and insignificant impact on grass biomass production, forb densities, species richness and diversity in short term, but fire impact on these plant attributes also depend on the intensity of fire and time frame.