Suddenly it is fashionable to write books on the geomorphology of drylands. In the last five years more all-encompassing textbooks on the subject have been published in the English language than in the previous century. We have seen volumes on specific process domains in drylands: Graf (1987) on rivers, Pye and Tsoar (1990) on dunes, and Parsons and Abrahams (1992) on overland flow with a strong dryland slant.
Books on particular deserts, emphasizing their geomorphology, have also appeared: on the Namib (Lancaster, 1989) and the Kalahari (Thomas and Shaw, 1991). Is this simply a function of more geomorphological books being published, or is it a function of a genuine increase in knowledge about physical environments in drylands, requiring summary and dissemination in book form? Drylands are certainly important, with U.N. data indicating that hyperarid to dry subhumid realms (the recognized scope of dryland or arid environments) occupy over 40 per cent of the global land area and support over 17 per cent of the world human population. A growing dryland geomorphology subdiscipline can therefore be justified, and these books show its distinctiveness, if not in specific process domains, then in process significance and operation.
It is impossible not to compare Geomorphology of Desert Environments with other texts, as its editors do in their preface. They claim their book to be distinct from Arid Zone Geomorphology (Thomas, 1989) and Desert Geomorphology (Cooke et al., 1983) in being pitched at a higher level and assuming prior knowledge of desert geomorphology. It is certainly different from these two books in several respects. It is larger, having 26 (many in-depth) chapters in eight sections, where Thomas has 16 chapters in three sections and Cooke et ul. have 31 (often short) chapters in five sections. It has a beautiful cover. It also has a price tag almost twice the combined cost of the other two books. The overall organization of all three books is remarkably similar, progressing from introduction, through surface conditions, water and wind to environmental change. In Geomorphology of Desert Environments this progression takes the form of two introductory chapters (one being a comparison between selected deserts), four chapters in a weathering section including coverage of soils, duricrusts and varnish, four on hillslopes, two on rivers, two on piedmonts, two on lake basins, three on aeolian