man and environmental processes. k. j. gregory and d. e. walling (eds), dawson, folkestone, and...

EARTH SURFACE PROCESSES AND LANDFORMS, VOL. 6, 95-98 (1981)

BOOK REVIEWS

GEOMORPHOLOGICAL PROCESSES. E. Derbyshire, K. J. Gregory and J. R. Hails, Dawson, Folkestone, and Westview, Boulder (1979). No. of pages 312. ISBN 0-7129-0833-1, 0-7129-0923-0 Paperback (Dawson) and 0-89 158-695-4, 0-89 158-864-7 Paperback (Westview). Price f 10.00 (Hardback); f6.00 (Paper- back).

MAN AND ENVIRONMENTAL PROCESSES. K. J. Gregory and D. E. Walling (Eds), Dawson, Folkestone, and Westview, Boulder (1979). No. of pages: 276. ISBN 0-7129-0834-X, 0-7129-0922-2 Paperback (Dawson) and 0-89158-696-2,0-89158-865-5 Paperback (West- view). Price f l O . O O (Hardback); f6.00 (Paperback).

The first of a new series of Studies in Physical Geo- graphy these well-illustrated books seek to bring the current concerns of geomorphologists to the first- and second-year undergraduate textbook market by emphasizing processes and applications. Summarizing much of the literature of the nineteen-seventies, they will be helpful to specialists who have to venture into branches of geomorphology other than their own. I found the sections on coastal and periglacial processes interesting for this reason.

Of the two, the Geomorphological Processes book is most likely to be adopted as a text for it covers many of the process themes followed in first-year courses. It offers an introduction to earth materials, stress and strain and climatic factors before providing chapters on drainage basin (63 pages), coastal (55 pages) aeolian (25 pages) and cryonival and glacial (99 pages) processes. Drainage basin processes are discussed initially in terms of concepts and models, then descriptively in terms of the hydrologic cycle and the movement of solutes and sediment, then more theoretically in terms of the hy- draulics of slope and channel processes before a more descriptive account of spatial and temporal variations in the magnitude and frequency of processes. Channel changes are dealt with well, but controls of solute mobility, especially the roles of soils and vegetation, receive less attention.

The discussion of coastal processes precipitates the first-year geography undergraduate into equations of wave motion on its second page. The emphasis on hydrodynamics continues in the section on tides, but the way in which these forces interact with sediment to create shoreline features is discussed more descriptively. The brief chapter on aeolian processes relies heavily on the classic work of Bagnold, McKee and Folk, particular attention being paid to bedforms. This chapter is thus

curiously different from that on drainage basin processes where the analogous bedforms in channels and the work of Bagnold on sediment transport receive but passing reference.

The largest chapter devotes a lot of attention to glacial erosion and deposition and only 30 pages to periglacial processes. Again, the more fundamental flow mechanisms are treated quantitatively, but the numerate attempts fade away into description and even conjecture when the more elusive aspects of glacial processes, such as meltwater channels within ice, are discussed.

Overall there is much to commend the approach adopted in this book, but inevitably it suffers from being written by a triumvirate. A single author would probably have written more about the mechanics of erosion in the first chapter, he would probably have discussed clays more thoroughly and would have seen that particle size distributions were not tackled in different chapters. Students will find the book useful, especially because the diagrams are clear and informative. Their teachers will however point them to supplementary sources and good introductory books on the mechanics of erosion and the properties of earth materials. A major worry will be that the authors fail to emphasize that much of the world undergoes processes described in the drainage basin chapter for part of the year and either cryonival or aeolian processes the rest of the year.

The collection of essays on applied physical geo- graphy provides valuable additional reading for all undergraduates. Many chapters, such as those by Coates on subsurface influences and Gregory on river channels, are useful in applied geomorphology courses. The edit- ors’ aim to show students how physical geography may be put into practice are well met, even if a high propor- tion of the references are to the writings of engineers. However, perhaps the book tries to cover too much, thereby making some chapters too brief and others too concerned with basic principles to be able to discuss applications. The chapters on biogeographic themes suffer particularly from this effect. Nevertheless, the book is a welcome addition to the growing number of collections of essays on useful physical geography.

These two books indicate that Dawson and Westview may have begun an exciting new series which will chal- lenge some of the traditional publishers in physical geographers.

IAN DOUGLAS University of Manchester

@ 1981 by John Wiley & Sons, Ltd.

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