A patch mosaic burning system for conservation areas in southern African savannas

Fire-prone savanna ecosystems in southern African conservation areas are ma naged by prescribed burning in order to conserve biodiversity. A prescribed burning system designed to maximise the benefits of a diverse fire regime in savanna conservation areas is described. The area burnt per year is a fu nction of the grass fuel load, and the number of fires per year is a functi on of the percentage area burnt. Fires are point-ignited. under a range of fuel and weather conditions, and allowed to burn out by themselves. The sea sonal distribution of planned fires over a year is dependent on the number of fires. Early dry season fires (May-June) tend to be small because fuels have not yet fully cured, while late season fires (August-November) are lar ger. More fires are ignited in the early dry season, with fewer in the late dry season. The seasonality, area burnt, and fire intensity are spatially and temporally varied across a landscape. This should result in the creatio n of mosaics, which should vary in extent and existence in time. Envelopes for the accumulated percentage to be burnt per month, over the specified fi re season, together with upper and lower buffers to the target area are pro posed. The system was formalised after 8 years of development and testing i n Pilanesberg National Park, South Africa. The spatial heterogeneity of fir e patterns increased over the latter years of implementation. This fire man agement system is recommended for savanna conservation areas of >20 000 ha in size.