Frequent low intensity fires can have a large impact compared with one-off, intense fires. Different combinations of these factors can benefit or disadvantage different elements of the ecosystem. Some plant and animal species, especially the ‘pioneer species’, benefit from frequent fires. Other species are favoured by long fire intervals; in fire-prone landscapes, these are provided for by protected situations such as deep sheltered gullies.
The most dramatic environmental impact is caused by large, high intensity fires. These result in localised and usually temporary loss of plants, animals and habitat, but also stimulate the regeneration of many plant species. The result of such fire can therefore be even-aged regeneration over wide areas, loss of species which prefer frequently or mildly burnt forest, and potential degradation of soils and waterways. Understanding of forest fire ecology suffers from limited data, the time-frames over which recovery occurs and the complexity of interactions between fire regimes and forest types. Most is known about the ecological impacts of fairly frequent (<10 years interval), high intensity fires, especially in shrublands, and woodlands.