There is currently great interest in the biology of soil, stimulated by
an increased concern to conserve natural resources, not only in
agriculture but also in natural ecosystems. Recent developments in
molecular biology have increased the possibilities of manipulating soil
organisms and the processes they carry out, to improve food production
and the quality of the environment. But important environmental
questions associated with the application ofthis new biotechnology to
soils are still to be resolved. Issues such as the desirability of using
genetically-engineered microorganisms in soil can be discussed sensibly
only in the light of an understanding of naturally-occurring organisms
in soil. Although on a global basis food production continues to
increase, man's current relationship with the soil in many parts ofthe
world is characterised by decreasing soil fertility and increasing
population pressure. Soil Science has an important role to play in the
future, helping to solve these problems. Although not all areas of this
large and expanding subject are covered in this book, I hope that I have
been able to present the principles of soil biology in such a way that
will interest the reader.