INTRODUCTION

Soil is an important component of most terrestrial ecosystems. Soils, through their physical structure, physico-chemical properties and biological activities, are driving variables controlling the structure and function of the ecosystem they support. The soil of course does not exist in isolation, it is part of the ecosystem, which includes soils, micro-organisms, plants, animals and dead material, which all interact. The entire system reflects the management that humans impose on it and, clearly, any management impact in any one part of the system may have serious implications for the structure of the system or its processes. As we more or less take this for granted in ‘normal’ ecosystems, it should be no surprise that we need to manipulate soil processes during restoration work.

There is, however, a fundamental difference in the way that soil is viewed by restoration ecologists compared with ‘normal’ ecosystems; the starting soil material is often inadequate to support the target ecosystem. The soil must, therefore be manipulated during the restoration process in order to rectify this problem, and in most instances an ecological approach can help match soil properties with an appropriate target ecosystem (Marrs, 1993; Marrs & Bradshaw, 1993). Often, soil manipulation can involve a large number of management techniques. Whereas some treatments affect the soil directly, indirect techniques that operate via plant growth or management (e.g. cropping, grazing or burning) are also often used.