The authors are grateful to Dr. B. Jacobs for discussions in the planning phase, to B. Schurle for his comments on an early draft of Chapter 6 and to Dr. C.S. Ofori for discussions arising from the manuscript. The text was edited substantially for publication by J.M. Hodgson. Cover photograph (J.C. Griesbach): soil saving dams and fish-scale terracing on slopes, Loess Plateau, China.
