spatial patterns in catchment hydrology: observations and modelling edited by roger grayson and...

Earth Surface Processes and LandformsEarth Surf. Process. Landforms 27, 681–685 (2002)

BOOK REVIEWS

SPATIAL PATTERNS IN CATCHMENT HYDROLOGY:OBSERVATIONS AND MODELLING edited by RogerGrayson and Gunter Bloschl, Cambridge University Press,Cambridge, 2000. No. of pages: 404. Price: £65.00. ISBN0 521 63316 8.

This is a landmark volume. In ten years’ time hydrolo-gists may well look back and identify this publication asthe point when distributed modelling finally came of age.Whilst distributed models have been used in hydrologyfor the best part of two decades, measurement programsand our understanding of the spatio-temporal dynamicsof catchment processes have not developed to allow thispotential to be exploited. Comparison of such codes withbulk catchment runoff has been widely acknowledged asa poor test and gives little insight into internal catchmentprocesses. Nevertheless, such data are frequently all thatare collected and hence very few studies have attemptedvalidation of distributed codes against distributed data.The consequence has been a rather superficial level ofinvestigation in hydrological modelling and without amove to the analysis of distributed data the commentsof Klemes (1986) regarding dilettantism in hydrology stillring true. A consideration of spatial patterns brings a num-ber of benefits, not least the potential to transform hydrol-ogy into a mature geoscience with a focus on understand-ing the non-linear interaction of complex process assem-blages across wide space and time scales. This challengeis important both scientifically and because the solutionof many key environmental problems worldwide requiressuch knowledge. However, because of the lack of the rig-orous analysis of the type proposed here it is probablybeyond the ability of many current modelling and field-work programs to deliver such advances. Roger Graysonand Gunter Bloschl argue successfully in this volume thatmeasurement of spatial patterns is necessary to further ourunderstanding of hydrological processes and to properlytest and develop spatially explicit hydrological models.

The book commences with five chapters on fundamen-tal issues including pattern organization, observation/inter-polation and modelling. Three of these contributions areby the editors themselves and this gives the comprehen-sive coverage necessary to carefully outline the method-ological basis of spatial analysis in hydrology. The mainpart of the book consists of seven case studies wherespatial data have been used in model analysis or areaswhere good potential for such work exists. The authorlist is comprehensive and includes the major work in thisfield. The applications are, perhaps necessarily, drawnfrom small, well instrumented research catchments andare characterized by their need for research teams thatintegrate the skills of field workers and modellers. Thebook concludes with a chapter by Jens Refsgaard, which

puts forward a formal framework for model calibrationand validation using distributed data, and a summary chap-ter by the editors. The production by Cambridge Uni-versity Press is excellent, especially given the relativelymodest price.

A number of general themes emerge as one reads thisvolume, the most significant of which is the genuineexcitement conveyed by the authors for the brave newworld they are opening up. Here is a hydrological sciencewith intellectual challenge, ambition and technical rigourthat is able to compete on an equal footing with othergeosciences. To date such work has largely been confinedto those hydrologists dealing with land surface forcingeffects on the atmosphere and climate as embodied inthe GEWEX program and it is this approach that weneed to feed through into other areas of the discipline.It is also clear that spatial pattern research will requirea step-change in the scale of hydrological experimentsand the resources required. The best examples in thisbook, such as the work at Walnut Gulch, Arizona,summarized by Houser et al., require considerable fieldinstallation combined with airborne/satellite monitoringand significant modelling resources. Hydrologists willneed to be much more successful in persuading fundingbodies to support large-scale experiments in hydrologythan perhaps has previously been the case in anythingother than the hydroclimatology field.

A further theme emphasized by the volume is the needto link more explicitly modelling and data collection,in the form of either fieldwork or remote sensing. It isincreasingly clear that progress can only be sustained ifthese are integrated and that practitioners of each ‘art’actually talk to each other. Personal experience shows thatthere is nothing like applying a model to a field site to finderrors in the data. Without this link it is too easy for mod-ellers to produce results that cannot be verified or for col-lected data to be insufficient to parameterize a model. Thecurrent default position is that we merely generate whatHillel has called ‘an ever deepening sea of unrelated facts’(Hillel, 1986, quoted by Grayson and Bloschl, p. 355).

The overriding desire of the editors in advocating re-search into spatial variation in hydrology is to give asound scientific base to the discipline. It is clear thatlumped conceptual models, and distributed schemes thatoperate in the same way (cf. Beven, 1989), have limiteduse as scientific tools to investigate basic hydrologic pro-cesses, as they predict but do not explain. Rather, we needto develop a new toolkit of spatial analysis techniques,new models capable of making use of high-resolution spa-tial data and a real integration of remotely sensed datawith distributed models if we wish to place hydrology ona par with meteorology and oceanography. Grayson and

Copyright 2002 John Wiley & Sons, Ltd.

682 BOOK REVIEWS

Bloschl provide a compelling argument why a considera-tion of spatial pattern is essential to the immediate devel-opment of hydrologic science and it will be instructive tochart how we as hydrologists take up this challenge.

REFERENCES

Beven KJ. 1989. Changing ideas in hydrology: the case ofphysically based distributed models. Journal of Hydrology105: 157–172.

Klemes V. 1986. Dilettantism in hydrology: transition or destiny.Water Resources Research 22: 177S–188S.

PAUL BATES

School of Geographical Sciences University of Bristol

Published online in Wiley InterScience(www.interscience.wiley.com).

DOI: 10.1002/esp.378

ECOLOGY AND GEOMORPHOLOGY OF COASTALSHINGLE edited by J. R. Packham, R. E. Randall,R. S. K. Barnes and A. Neal, Westbury Academic andScientific Publishing, Otley, West Yorkshire, 2001. No.of pages: 459. Price: £48.00. ISBN 1 84103 007 4.

This edited volume is the product of a symposiumorganized by the UK branch of the European Union forCoastal Conservation (EUCC-UK) in April 1999. Thegeneral theme of the book addresses a perceived gapin the literature on coastal systems based on granulardeposits and, as such, contains invited contributions fromrecognized authorities on shingle deposits from acrossEurope. Hence, it may be regarded as a state-of-the-art review of the geomorphology and ecology of coarseclastic coastal environments, as well as many allied issuessuch as management, coastal defence and conservation;human impact; sediment budgets and dynamic controls;innovative approaches for research and monitoring; andstudies of related environments such as sandy beaches andlagoons. The ultimate goal is creditworthy and, indeed,long overdue: coarse clastic barriers are not uncommonand are of some significance, not only from a scientificperspective but also from the reliance of certain coastalpopulations and economies on well-maintained barrierbeach environments.

The text is divided into four sections that deal in turnwith the geomorphology, the plants, other flora and fauna,and management and conservation of shingle environ-ments. It is an impressive array of papers and clearlyaims to cover all aspects of relevance in order to presenta comprehensive review of coastal shingle. The coher-ence of these sections is, however, somewhat inconsistentand imbalanced, but there is still a wealth of informa-tion and interest contained within each. The breadth ofthe subject matter and, by association, that of the targetaudience requires an introductory section on methods andterminology. This is admirable, but the material containedwithin is very disappointing. The geomorphological partof this introduction looks only at particle size (in whichthe ambiguity of the term ‘shingle’ becomes clear) andbreaking waves, whilst the ecological part focuses on theassessment and multivariate statistical analysis of vege-tation cover and classification. Although ‘Methods andterminology’ is an accurate description of the contents,this section does not provide the necessary basis for the

geomorphologist to appreciate the ecological material pre-sented in subsequent chapters, and the same would be truefor the biologist with a geomorphic interest.

The opening set of papers on ‘Geomorphology,sediment dynamics, hydrology and soils’ is a markedcontrast to the sketchy introduction. The chapter byPye on the geomorphology, sedimentology and dynamicsof shingle environments provides an explanation ofthe occurrence of coastal shingle, with an emphasison the UK, and presents a review of various coarseclastic landforms from both geomorphological andsedimentological perspectives. This then enables theresponse of shingle environments to environmentalforcing to be considered, particularly in the context offuture management. The theme of change and responseis taken up in the following chapter by Orford et al.on the origin and evolution of coastal barrier systemsin Canada and the UK. The sequence of barrierinitiation, consolidation and breakdown observed in NovaScotia highlights the importance of timescales in bothprocess and response – from which long-term controlson gravel accumulation, and barrier response to futuresea-level rise, are examined in relation to UK examplesfrom Porlock and The Crumbles. Bluck et al. thenpresent a detailed sedimentological and morphologicalreview of gravel beaches in Namibia. This chapterworks through the stratigraphic record of barrier andlagoonal environments to arrive at an understanding ofbarrier and back-barrier sedimentation in both shore-normal and shore-parallel directions. It is an excellentcontribution and is worthy of reference in studies ofbarrier progradation worldwide. The following chapterby Neal et al. illustrates the application of ground-penetrating radar to the study of barrier stratigraphy inthe Isle of Man and the Solway Firth. Given the difficultyin obtaining stratigraphic records from unconsolidatedgravels and sands, the potential of GPR is of considerablesignificance in improving our understanding of Holocenebarrier origin and evolution. The link made between theradar stratigraphy and sedimentary sequences and faciesin these two examples is convincing, and suggests thatthe technique is of some merit in future research ofthis nature. The hydrology and soils of Dungeness areconsidered by Burnham and Cook – the first theme in astudy of groundwater levels in the Dungeness aquifer andthe supply of water to shingle plant communities, and

Copyright 2002 John Wiley & Sons, Ltd. Earth Surf. Process. Landforms 27, 681–685 (2002)