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Assessment of Erosion
Earth-Science Reviews, 18 (1982) 77--107
77
Elsevier Scientific Publishing Company, Amsterdam - Printed in The Netherlands
Book Reviews GEOMORPHOLOGY M. de Boodt and D. Gabriels (Editors), 1980.
Assessment o f Erosion. Proceedings of the Workshop on Assessment of Erosion in the U.S.A. and Europe, Ghent, 1978, John Wiley, Chichester X V I I I + 5 6 3 p p . , £stg. 27.50. This volume contains 56 papers presented at a Workshop on Assessment of Erosion in Europe and the USA held at Ghent in 1978. The regional emphasis is strongly European. Of 40 papers treating regional topics, 28 relate to Europe and only 5 to the U.S.A. The remaining regional papers, despite the original theme, relate to Africa. Given this emphasis, it is not surprising that 61 of the 86 authors are based in Europe; the host-country Belgium is welt represented, as are the U.K., Germany and France, but Eastern and Mediterranean Europe are not. The workshop status of the papers is clearly apparent; none is long and some, with only about 300 words are very short. Moreover, individual papers are c o m m o n l y in the nature of interim reports, outlining the progress of w o r k , or outlining a technique or research programme, or presenting a sample of results. The editors have subdivided the material into four main parts: erosion mapping (gpapers); erosivity (9); erodibility (10); miscellany (28). This arrangement is less than ideal and tends to disguise important themes that can be traced through the volume. Firstly, although the workshop was
mainly concerned with wash and rainsplash, there are several papers on other processes, notably solute behaviour, and these merit separate recognition in the volume. Secondly, a recurrent theme is the Universal Soil Loss Equation (USLE). However, this is approached in various different ways and it is these attitudes that are particularly interesting. They can be summarised as follows: (a) rejection and development of alternative procedures; (b) modification for use outside the eastern U.S.A., particularly in tropical areas; (c) detailed studies of the physical basis of the equation; (d) acceptance and application, including the mapping of relevant parameters. In addition to studies related to the USLE, mapping of soil erosion is represented, including the use of infra-red photography and Landsat imagery; and experimental investigations of process are described, including high-speed cine-photography of rain-splash. An area of potential development is briefly noticed in three papers on the mathematical modelling of soil erosion. The economic context of soil erosion is treated in papers on crop yield and agricultural policy, and its broader environmental c o n t e x t in a paper on reservoir pollution, If this volume is read from cover to cover, it gives a clear impression of the main directions of contemporary research in Europe and North America into soil erosion. It is difficult to imagine, however, that anyone will read it in this way, and the individual papers are so obviously 'Workshop' contributions that few substantive data can
78
be derived from them. It is perhaps unwise to give such ephemeral material the status that formal publication tends to imply. However, in the present case such f o r m a l i t y is somewhat offset by reproduction from a t y p e - w r i t t e n t e x t , and by the survival of typographic and linguistic errors that are the normal stuff of w o r k s h o p meetings. Christopher P. Green, London
Cliff Oilier, 1981. Tectonics and Landforms. G e o m o r p h o l o g y Texts, 6, Longman Group Ltd, 324 pp., paper: £stg. 9 . 9 5 , cloth: £st. 20.00. It is certainly true that geomorphology has, as is argued in Chapter 21 of this b o o k , ignored the influence of tectonics. To some e x t e n t of course this depends upon the definition of the content and scale of geom o r p h o l o g y . 'The description, the form and origin of landforms . . . ' taken as the definition in this b o o k may be at variance w i t h the d e f i n i t i o n currently adopted by many geomorphologists to include greater import ascribed to processes. In the final chapter it is contended (p. 300) that 'To play a part in the problems of geology over the n e x t few decades gemorphologists must forget their trivial catchments and see megaforests instead of trees'. This t y p e of assertion is echoed elsewhere in the b o o k and whereas many geomorphologists may agree that what is here described as e v o l u t i o n a r y geomorphology could be developed as an adjunct to existing research, not all w o u l d see this approach as a new basis for geomorphology to replace existing paradigms. This b o o k p o t e n t i a l l y fills a gap in the modern literature. Emphasis is overwhelmingly on the English language literature (more than 97% of the references) which is surprising in view of the greater adherence to a tectonic v i e w p o i n t in the geomorphology of France, Germany and the U.S.S.R.; it is on the past development rather than on c o n t e m p o r a r y tectonic activity so that the countries of recent earthquakes such as Italy, T u r k e y , Iran, China do n o t feature in the index; and curiously there is no reference to the ideas of tectonic relief promulgated by C.A. Cotton. A l t h o u g h process studies are decried in
this book surely the geomorphologist has much to learn from the effects of recent earthquakes and volcanic eruptions upon landforms although these are not reviewed in this t e x t . What is included is a basic i n t r o d u c t i o n which provides definitions and frames of reference for temporal and spatial scales and a final chapter which reviews geomorphological paradigms and concludes that e v o l u t i o n a r y geomorphology provides the way ahead. This chapter affords a necessary c o n t e x t for the approach taken in the book and it is not easy to see w h y it was not placed at the beginning. In addition it w o u l d have been useful to have a short review showing how geomorphologists have approached tectonics, pin pointing the intellectual milestones of the last 30 years or so. Between these t w o chapters are eighteen which fall into t w o types directly and indirectly related to tectonics and Chapter 20 which provides some regional examples. The direct chapters provide clear and wellillustrated reviews of the topics that one w o u l d expect to find including continental d r i f t and sea f l o o r spreading, plate tectonics, structural and tectonic landforms, volcanoes, island arcs, the expanding earth and theories of mountain and plateau formation. It was not clearly apparent w h y they had been arranged in the sequence adopted and w h y a second group of chapters covering less obviously related topics such as the f l o w of ice and rock, planation surfaces and sea level changes were intermixed in the sequence. These chapters certainly present material in an interesting way and the chapter on the expanding earth is particularly valuable. However, t h r o u g h o u t the b o o k it is sometimes d i f f i c u l t to decide the level of reader expected because certain basic material on erosion or glacier movement for example is included and throughout the emphasis is upon macrofeatures such as fold and fault landforms, lineaments and drainage patterns and there is no attention to the detail produced in recent tectonic events. Overall the b o o k is a stimulating and t h o u g h t - p r o v o k i n g t e x t which should certainly be of interest to students following those courses which introduce tectonics in relation to geomorphology. A t present the material contained is heavily dependent
77
Elsevier Scientific Publishing Company, Amsterdam - Printed in The Netherlands
Book Reviews GEOMORPHOLOGY M. de Boodt and D. Gabriels (Editors), 1980.
Assessment o f Erosion. Proceedings of the Workshop on Assessment of Erosion in the U.S.A. and Europe, Ghent, 1978, John Wiley, Chichester X V I I I + 5 6 3 p p . , £stg. 27.50. This volume contains 56 papers presented at a Workshop on Assessment of Erosion in Europe and the USA held at Ghent in 1978. The regional emphasis is strongly European. Of 40 papers treating regional topics, 28 relate to Europe and only 5 to the U.S.A. The remaining regional papers, despite the original theme, relate to Africa. Given this emphasis, it is not surprising that 61 of the 86 authors are based in Europe; the host-country Belgium is welt represented, as are the U.K., Germany and France, but Eastern and Mediterranean Europe are not. The workshop status of the papers is clearly apparent; none is long and some, with only about 300 words are very short. Moreover, individual papers are c o m m o n l y in the nature of interim reports, outlining the progress of w o r k , or outlining a technique or research programme, or presenting a sample of results. The editors have subdivided the material into four main parts: erosion mapping (gpapers); erosivity (9); erodibility (10); miscellany (28). This arrangement is less than ideal and tends to disguise important themes that can be traced through the volume. Firstly, although the workshop was
mainly concerned with wash and rainsplash, there are several papers on other processes, notably solute behaviour, and these merit separate recognition in the volume. Secondly, a recurrent theme is the Universal Soil Loss Equation (USLE). However, this is approached in various different ways and it is these attitudes that are particularly interesting. They can be summarised as follows: (a) rejection and development of alternative procedures; (b) modification for use outside the eastern U.S.A., particularly in tropical areas; (c) detailed studies of the physical basis of the equation; (d) acceptance and application, including the mapping of relevant parameters. In addition to studies related to the USLE, mapping of soil erosion is represented, including the use of infra-red photography and Landsat imagery; and experimental investigations of process are described, including high-speed cine-photography of rain-splash. An area of potential development is briefly noticed in three papers on the mathematical modelling of soil erosion. The economic context of soil erosion is treated in papers on crop yield and agricultural policy, and its broader environmental c o n t e x t in a paper on reservoir pollution, If this volume is read from cover to cover, it gives a clear impression of the main directions of contemporary research in Europe and North America into soil erosion. It is difficult to imagine, however, that anyone will read it in this way, and the individual papers are so obviously 'Workshop' contributions that few substantive data can
78
be derived from them. It is perhaps unwise to give such ephemeral material the status that formal publication tends to imply. However, in the present case such f o r m a l i t y is somewhat offset by reproduction from a t y p e - w r i t t e n t e x t , and by the survival of typographic and linguistic errors that are the normal stuff of w o r k s h o p meetings. Christopher P. Green, London
Cliff Oilier, 1981. Tectonics and Landforms. G e o m o r p h o l o g y Texts, 6, Longman Group Ltd, 324 pp., paper: £stg. 9 . 9 5 , cloth: £st. 20.00. It is certainly true that geomorphology has, as is argued in Chapter 21 of this b o o k , ignored the influence of tectonics. To some e x t e n t of course this depends upon the definition of the content and scale of geom o r p h o l o g y . 'The description, the form and origin of landforms . . . ' taken as the definition in this b o o k may be at variance w i t h the d e f i n i t i o n currently adopted by many geomorphologists to include greater import ascribed to processes. In the final chapter it is contended (p. 300) that 'To play a part in the problems of geology over the n e x t few decades gemorphologists must forget their trivial catchments and see megaforests instead of trees'. This t y p e of assertion is echoed elsewhere in the b o o k and whereas many geomorphologists may agree that what is here described as e v o l u t i o n a r y geomorphology could be developed as an adjunct to existing research, not all w o u l d see this approach as a new basis for geomorphology to replace existing paradigms. This b o o k p o t e n t i a l l y fills a gap in the modern literature. Emphasis is overwhelmingly on the English language literature (more than 97% of the references) which is surprising in view of the greater adherence to a tectonic v i e w p o i n t in the geomorphology of France, Germany and the U.S.S.R.; it is on the past development rather than on c o n t e m p o r a r y tectonic activity so that the countries of recent earthquakes such as Italy, T u r k e y , Iran, China do n o t feature in the index; and curiously there is no reference to the ideas of tectonic relief promulgated by C.A. Cotton. A l t h o u g h process studies are decried in
this book surely the geomorphologist has much to learn from the effects of recent earthquakes and volcanic eruptions upon landforms although these are not reviewed in this t e x t . What is included is a basic i n t r o d u c t i o n which provides definitions and frames of reference for temporal and spatial scales and a final chapter which reviews geomorphological paradigms and concludes that e v o l u t i o n a r y geomorphology provides the way ahead. This chapter affords a necessary c o n t e x t for the approach taken in the book and it is not easy to see w h y it was not placed at the beginning. In addition it w o u l d have been useful to have a short review showing how geomorphologists have approached tectonics, pin pointing the intellectual milestones of the last 30 years or so. Between these t w o chapters are eighteen which fall into t w o types directly and indirectly related to tectonics and Chapter 20 which provides some regional examples. The direct chapters provide clear and wellillustrated reviews of the topics that one w o u l d expect to find including continental d r i f t and sea f l o o r spreading, plate tectonics, structural and tectonic landforms, volcanoes, island arcs, the expanding earth and theories of mountain and plateau formation. It was not clearly apparent w h y they had been arranged in the sequence adopted and w h y a second group of chapters covering less obviously related topics such as the f l o w of ice and rock, planation surfaces and sea level changes were intermixed in the sequence. These chapters certainly present material in an interesting way and the chapter on the expanding earth is particularly valuable. However, t h r o u g h o u t the b o o k it is sometimes d i f f i c u l t to decide the level of reader expected because certain basic material on erosion or glacier movement for example is included and throughout the emphasis is upon macrofeatures such as fold and fault landforms, lineaments and drainage patterns and there is no attention to the detail produced in recent tectonic events. Overall the b o o k is a stimulating and t h o u g h t - p r o v o k i n g t e x t which should certainly be of interest to students following those courses which introduce tectonics in relation to geomorphology. A t present the material contained is heavily dependent