Short-Term Influence of Burning on Species Abundance, Biomass Production, Wood Plant Density and Browsing Unit in an Albany Thicket of the Eastern Cape, South Africa

Abstract

Fire is regarded as management practice for maintaining grasslands and sa-vannas. The vegetation occurring in fire prone areas becomes highly adapted to fire occurrences in savannas and grasslands. However, documentation on the influence of burning on vegetation is still limited in an albany thicket bi-ome. The aim of the study was to evaluate the short-term influence of burning on species abundance, biomass production, wood plant density and browsing unit. Six plots (2500 m 2) were demarcated; in each plot two parallel tran-sects of 120 m 2 with 5 m distance apart were measured. Three plots were burned in spring season, while no burning was done on the other remaining plots. Forty points per plot were obtained using step-point method to determine the relative abundance at burned and unburned plots. Woody plants occurred within a transect were identified, counted and recorded to determine density and browsing unit. Three quadrats (i.e. 0.25 m 2) per plot were randomly laid within the transect; aboveground plant material within a quadrat were harvested. A total of 18 samples were harvested and oven dried at 60˚C for 48 hours to determine biomass production. The results showed that Themeda triandra (14%) and Panicum maximum (10%) were most abun-How to cite this paper: Tokozwayo 75 Agricultural Sciences dant grass species at the burned plots. Burned plots had significantly higher biomass production (4804 kg/ha) compared to unburned plots (3641 kg/ha). Vachellia karoo (burned: 65.85% & unburn: 13.70%) and Searsia pallens (burned: 26.83% & unburned: 6.85%) were most dominant wood plant species at both burned and unburned plots. Burned plots had the highest browsing unit (3221 BU/ha) compared to unburned plots (2058 BU/ha). The decrease of woody plants at the burned plots proved that fire has a tremendous potential for managing woody plants. This study provided information on short-term influence of burning, however further long-term trials are required to determine the effects of burning.