The soil which has developed at any given location is considered to be
the result of five interacting factors: parent material, time, climat
e, topography and biotic factors. This paper discusses the role of the
se factors in the development of Scottish soils, which fall into three
broad categories: leached soils, gley soils and organic soils. The in
tention is to provide a context for the case studies that follow in la
ter papers.