ABSTRACT
Soils are a complex, multivariate medium which play an important role in all environmental disciplines (section 1.2). Consequently it is necessary to understand the way in which they vary spatially and how their characteristics are suited to various forms of environmental investigation and utilisation. The spatial variation in soils has been recognised since the earliest times through its influence on agriculture, drainage and, therefore, human settlement. The earliest surveys were concerned primarily with basic agricultural characteristics such as texture and drainage (Avery 1990), but with the development of the environmental sciences during the twentieth century, soil survey became more sophisticated and aimed at a wider range of users, so that today there are now many types of survey, showing a variety of information at a range of different scales (Olson 1981a). Closely related to soil survey is land evaluation, whereby land is assessed on the basis of its suitability for particular purposes. In the first part of this chapter we will examine the methods of soil survey and land evaluation. This will then be followed by a discussion of the applications of the resulting information for both agricultural and non-agricultural purposes.
