Introduction

Those who are reading sequentially through this volume from beginning to end will have by now felt the need to examine the physical basis of flooding which partially underlies flood hazards and disasters and which complements explanations of the social, economic and political basis developed in the preceding Parts. The contributions to Part VII are therefore designed to take us further into the physical basis of flood-producing processes, and the important effects that human activities have upon the natural environmental processes which influence flood generation. Chapter 1 describes the principal types of floods and some of their characteristics and in Parts II-VI authors refer to a wide variety of flooding types and characteristics. This coverage is now expanded upon in Part VII. A number of authors have asserted that socio-economic processes such as urbanisation and deforestation may be responsible for causing or worsening flood hazards and disasters (see, for example, Montz, Chapter 7, and Mahmud, Chapter 26), and in Part VII we examine the scientific evidence for such assertions.