Arid ecosystems lack treefall and use distinct disturbance agents

Evidence

In arid and semiarid systems there is no counterpart of the treefall disturbance that is so important in generating patchiness in forested habitats (see Runkle, Chapter 2, and Brokaw, Chapter 3, this volume). Instead, most distur­ bance of an existing environment-vegetation mosaic is through erosion by water or wind, fire, or the actions of animals in disturbing the soil [e.g., burrowing mam­ mals (Piatt, 1975; Loucks et al., Chapter 5, this volume)], clearing areas of vegeta­ tion and harvesting nutrients to a central place [e.g., ants (Wiens, 1976; Culver and Beattie, 1983)], or grazing by domestic herbivores (Crisp, 1978; Risser et al., 1981). — S. T. A. Pickett and P. S. White, eds., The Ecology of Natural Disturbance and…, 1143

Categorization

• XREF: Contrast with forest treefall-gap chapters (2,3) shows disturbance agents differ by biome — a taxonomy the reader’s reference vocabulary should hold. — connects to: Conservation must protect disturbance regimes, not just taxa, to preserve biodiversity — S. T. A. Pickett and P. S. White, eds., The Ecology of Natural Disturbance and…, 1120