Over recent years, there has been a remarkable rise in the perceived importance of soil chemistry. A couple of decades ago, it tended to be regarded either as a small subdivision of agriculture and horticulture, or as a subject studied for its own interest by a handful of perhaps slightly eccentric physical or organic chemists. Today it is regarded by many as a subject at the core of environmental science. The change has been brought about largely by the worldwide recognition of the vital (and much wider) role played by soil, in controlling the air we breathe, the water many of us drink, and the extent of damage by pollution. In soil chemistry textbooks, however, tradition has largely prevailed, and the main thrust has been on discussion of soil as a medium for plant growth.

The authors decided that the time had come for a rather different approach, and set about preparing this volume. Their aim was to introduce students to the nature of soils, soil processes and soil formation, but in a much broader context than soil fertility alone.

Of necessity they have had to be selective, and no doubt in so doing will not satisfy all potential users of the book. However they hope that the message will get across to students that an understanding of soil chemical behaviour is crucial in the modern world, and that soil is dynamic, so that soil and soil problems are constantly changing.