These papers demonstrate the important role played by soils in the function of both natural and managed ecosystems. Understanding the impact of environmental factors on these ecosystems therefore requires a knowledge of soil processes ranging from molecular to landscape in scale. The properties and spatial distribution of soils and their mineral constituents are especially useful as indicators of both present and past environmental conditions. Soils and soil minerals form or transform in direct response to biogeochemical factors that are driven by local, regional or global processes. Through a series of case studies, this text demonstrates that linkages can be made between measurable soil and mineral properties and the processes that shape the weathering environment. Examples include layer silicates, carbonates, sulfides, and both iron and aluminium oxides. Several papers also emphasize the role of biotic factors in soil systems, the sensitivity of these factors to management practices, and the frequently overlooked interactions that exist between organic and inorganic compartments of soils and surface waters. Finally, this text recognizes that spatial and temporal variability are inherent attributes of soils and landscapes that must be quantified and properly managed if ecological and environmental harmony are to be maintained. The buffering function of soils and the importance of this function to the release and flux of nutrients in terrestrial ecosystems are given special consideration.