ABSTRACT
Site types usually differ not only in their potential productivity of materials useful to people, but also in their susceptibility to degradation under use. Consequently, they also differ in the types of land use that can be practised sustainably on them. In general, more productive sites can sustain a wider range of land uses, while the range becomes increasingly restricted as site quality declines. For example, the alluvial soils of floodplains could be used sustainably for forestry, tree crops, pastures, dryland annual crops or irrigated rice culture. Gently sloping lands adjacent to floodplains may be usable sustainably for forestry, tree crops and pastures, while in more steeply sloping terrain only forestry could be practised without environmental degradation. In the steepest terrain even forestry may be inappropriate, and a protective forest cover may be the only sustainable land use.
