ABSTRACT

Soil surveys usually include interpretations of their findings for land-use planning purposes in the form of land capability or suitability classifications. The aim of these classifications is to guide planning decisions, ideally in such a way that the resources of the environment are put to the most beneficial use, whilst at the same time conserving them for the future. The role of soil surveyors is normally concerned with the physical assessment of land resources, although this should always be seen in the broader context of a land evaluation which takes into account the technological and socio-economic consequences for the people of the area and the country concerned. Note that most agronomists and soil surveyors tend to use physical measures, such as potential yields per unit area, to build up an evaluation system, but such an approach may be inappropriate in some circumstances (eg under shifting agriculture, where much of the surface may be occupied by tree roots, fallen tree trunks etc). A more realistic measure, often overlooked in textbooks, is the return in yield or economic terms per person per unit of time worked. Such evaluations are however usually outside the scope of soil surveyors’ inputs to projects.