Patch-mosaic burning: a new paradigm for savanna fire management in protected areas?

Abstract

The shift in ecological thinking, from equilibrium to non-equilibrium processes has been accompanied by a move to encourage heterogeneity rather than homogeneity in landscapes. Spatial and temporal heterogeneity is thought to be a major source of biotic diversity, and disturbances such as fire, producing heterogeneity are now recognised as being important. A patch-mosaic system of burning is based on the premise that fire pattern is a surrogate for diversity, and produces a range of patches in the landscape with unique patch characteristics and fire histories. A patch-mosaic system of burning is supported historically and empirically through field studies. However, there is a need for more research into the effects of various aspects of patch and fire variables on biotic diversity, especially in savannas where our understanding is particularly poor. Landscape-scale experiments, like those to be established in the Kruger National Park, South Africa are necessary to test different burning regimes. Challenges to patch- mosaic burning include determining the 'natural' range of variation for fire parameters, implementing random ignitions, and cost-effective fire scar mapping at the appropriate resolution. An adaptive management approach should be adopted to deal with the ignorance and uncertainties that characterise the management of savanna ecosystems. This should be applied with both modelling and monitoring as key elements in this process.