Aquatic chemical kinetics, reaction rates of processes in natural waters

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this publication which presents a satisfactory if not exhaustive compendium of current research for interested oceanographers. ALAN WALTON (Rimouski, Qua.)

Productivity of the Ocean: Present and Past. W.H. Berger, V.S. Smetacek and G. Wefer (Editors). Report of the Dahlem Workshop on Productivity of the Ocean: Present and Past, Berlin 1988, April 24-29. Wiley, Chichester, 1989, xvii + 471 pp., £65 (hardcover), !SBN 0-471-92246-3. Although this book is ultimately concerned with the subject indicated by its title, it very quickly enters into the problems related to the fate of the organic matter in the ocean, its preservation in ocean sediments and the reconstruction of past marine productivity from the geological record. After an overview of ocean productivity and paleoproductivity by the three editors, the export of organic matter from the photic zone is discussed in the first section of the book, the resultant flux of organic matter to the seafloor in the second section, in the third section the transformation of the organic matter that is corporated in the bottom sediment, and the geological construction of past ocean productivity in the fourth section. In an appendix global maps of present ocean productivity are presented (by W.H. Berger). The book is a report of a Dahlem Workshop held in April 1988 and reflects the Workshop structure: each section consists of a number of separate contributions followed by a group report based on discussions held during the Workshop. It is the aim of the D~hlem Workshop to realize an interdisciplinary approach and the group reports reflect a wide range of knowledge and experience. This treatment is pre-eminently suitable for a complex subject like ocean productivity with its ramification into marine biology, chemistry, geology and hydrodynamics. The individual contributions are of excellent quality and on the whole are well worth reading. The downward flux of organic matter from the surface waters is in the first section related to the food-web structure, to various ecological factors ,~a~ the different types of surface circulation ('*singularities'" such as upwelling, tidal ,,nixing and

river outflow), to the downward flux of dissolved organic matter, and to the "new production" by nutrient input from outside the photic zone (in contrast to recycled nutrients). In the second section in three papers the vertical particle flux in the ocean is discussed as well as the organic particle flux from the shelf to the deep sea. In the third section benthic fluxes are related to particle supply, and the benthos to flux variations, followed by a paper on biomarkers. Estimates of productivity during the Pleistocene, Tertiary and Cretaceous in the fourth section are based on data of organic carbon, foraminifera, biogenic carbonate in general and biogenic silica. Two papers discuss phosphorus and nitrogen as limiting factors and modeling of the paleoproduction of atmospheric CO2 in relation to nutrients. The wide scope of the book makes it an important one: it contains a wealth of knowledge and suggestive ideas, and is at present by far the best publication on this subject. It can therefore be recommended to all marine geologists whose work is even remotely m related to the productivity of the ocean. D. EISMA (Den Burg, Texel)

Aquatic Chemical Kinetics. Reaction Rates of Processes in Natural Waters. W. Stumm (Editor). Wiley, Chichester, 1990, xii + 545 pp., £70.50 (hardcover), ISBN 0-471510297. In 1971, Werner Stumm and James J. Morgan published Aquatic Chemistry (Wiley-Interscience, New York), an attempt to synthesize a wide variety of topics in Environmental Science and Engineering under a framework constructed from the concepts of thermodynamic equilibria. It was extraordinarily successful, and the second (1981) edition is widely used and cited today. Now Stumm has edited a book of eighteen chapters by his students and colleagues - - physical and inorganic chemists, surface and colloid chemists, geochemists, oceanographers, aquatic chemists, chemical engineers, and environmental engineers m which attempts to unify nonequilibrium processes in Environmental Science and Engineering by applying the principles of chemical kinetics, ranging from elementary molecular reactions to colloid and surface processes.

BOOK REVIEWS

The 1971 book by Stumm and Morgan was primarily inorganic physical chemistry; this book includes a variety of organic and biochenfical examples as well. Each chapter, written by a separate author or co-author, stands alone as a review of a particular segment of the field; there is a small amount of duplication, but this is not troublesome. The sequence of topics proceeds from basic laboratory and theoretical studies of homogeneous systems (Chapters I-8) to reactions at surfaces (Chapters 9-11), mineral dissolution (Chapters 12-15), colloids (Chapter 16), comparison of laboratory and field studies (Chapters 17), and finally to an integration of transport and surface reactions (Chapter 18). Most of the chapters are written for a researchlevel audience; but the first chapter in particular is an extraordinarily clear and concise review of basic chemical kinetics by Alan Stone and James J. Morgan; this chapter could make a text suitable for part of a graduate-level course. The next chapters amplify these basics: aqueous photochemistry by Jiirg Hoign6, and catalysis in aquatic systems by Michael R. Hoffman. Patrick L. Brezonik reviews structure-activity and linee~r free-energy, relationships, including prediction of bioaccumulation from molecular connectivity index or from octanol-water partition coeflicknt, prediction of reaction rate from acidity consta,~t or from substituents on aromatic rings. N o t n g that trace metal ions in natural waters are usually present as organic or inorganic complexes, Janet G. Hering and Francois M.M. Morel review some examples of how complexation changes reaction kinetics of trace metals. George W. Luther, III applies frontier-molecular-orbital theory to geochemical process, with oxidation of hydrogen sulfide and sulfide minerals as the primary examples. In a later chapter, Bernhard Wehrli reviews redox reactions at mineral surfaces. Ren6 P. Schwarzenbach and Philip M. Geschwend review a variety of chemical transformations m such as hydrolysis, oxidation, :eduction m which organic pollutants might undergo in the aquatic envho~racnt. Extending the review to extracellular enzymes, Neii M. Price and Frang;ois M.M. Morel outline the possibilities of an important new field of environmental biochemistry. Beginning with adsorption of organic surface-

537

active agents at the mercury electrode, and their influence on electron-transfer processes such as reciuction of Cd 2+, Bo~cena Cosovi~ shows how these simple studies provide insight into the adsorption of organic materials found in natural waters. Returning to the theoretical approach, Antonio C. Lasaga and Gerald V. Gibbs describe ab initio quantum mechanical calculations of surface reaction kinetics, such as the hydrolysis of the Si-OSi structural unit at the surface of silicates. Jacques Schott describes a surface speciation approach to modeling the dissolution of multiple oxides, from basalt glass to albite. Werner Stumm and Erich Wieland show how dissolution rates of oxide and silicate minerals depend on surface speciation. One interesting example is the way ligands such as aspartic, citric, oxalic, salicylic, tartaric, and tannic acids promote the dissolution of clay minerals and change the stoichiometry of AI and Si release. Photochemical redox reactions at hydrous oxide surfaces such as Fe(Ill) and Mn(IV) promise novel photochemical energy conversion and wastewater treatment systems, and can be understood in terms of surface coordination chemistry, as Barbara Sulzberger describes. Roland Wollast reviews the rate and mechanism of calcium and magnesium carbonate dissolution, emphasizing the conditions typical of the aquatic environment, where dissolution rates near equilibrium are controlled by surface reactions as well as diffusion. Moving on to systems of colloids such as are found in groundwater aquifiers and lake sediments, Charles R. O'Melia shows data on transport, particle deposition, aggregation and sedimentation in real systems as well as in theory. Chemical weathering-dissolution of minerals by water and its solutes, particularly carbon dioxide and strong acids from precipitation, often involves diffusion-controlled or surface reaction-controlled incongruent dissolution. Field and laboratory experiments on Lead Mountain in Maine are described: one stream is artificially acidified; a similar one serves as a control. Transport and kinetics in surficial process are reviewed by Abraham Lerman, with an emphasis on transport and erosion as well as mineral dissolution. The book would have benefited from an author index, citing not only names in the text but also

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BOOKREVIEWS

all the authors in the eighteen separate bibliographies. Aside from this, design and production are up to Stumm's and Wiley's usual high standards. This is a book which will be a valuable addition to the library of every research and engineering group working on kinetic processes in the aquatic environment. J.N. BUTLER (Cambridge, Mass.)

Triassic-Jurassic Rifting. Continental Breakup and the Origin of lhe Atlantic Ocean and Passive Margins. Parts A (xxv + 523 pp.) and B (xi + 525-998 pp.). W. Manspeizer (Editor), Elsevier, Amsterdam, 1988, US$300, Dfl. 590 (hardcover), ISBN 0-444-42903-4. The essential point about these two fact-filled volumes is that they deal with the Atlantic Ocean (mainly the North Atlantic) during the critical time of its birth, when the ancient super-continent of Pangaea was breaking up and the present continents were drifting apart. There are 75 contributing authors and 39 papers. It would clearly be impossible and invidious to pick any of them out, but it must be pointed out that there are twice as many authors from the U.S.A. as from the rest of the world. France and Spain do comparatively well, but the rest of us are very poorly represented. Obviously therefore this work tends to concentrate on the western side of the ocean and on work by American geologists elsewhere. This is understandable since the work was originally intended for the American Association of Petroleum Geologists. Perhaps I should declare an interest in that I live on one of these passive margins and have been involved with rocks of this age not only in Britain, but in France, Spain, Portugal, Tunisia and Morocco. In the last-named I had the pleasure of working in the same team as Warren Manspeizer, who made the great effort of editing this work and contributing to it. However, I cannot help but note the comparative neglect of the vast literature on the Triassic and Jurassic of western Europe. I regret particularly the omission of my friend Michael Audley-Charles's important work on Triassic rifting and sedimentation in Britain and much of the work on rifting in the North Sea. Personally= I also regret that more use was not made of the

work of Swansea geologists in northwest Africa, west Africa and the Red Sea, though the coverage does extend that far and even to the Gulf of Aqaba and Lake Tanganyika. The book also extends back in time as far as the Carboniferous and the Variscan orogeny. Especially interesting are the numerous papers on the terrestrial sedimentary basins formed in Triassic times on both sides of the Atlantic. These include lake deposits and coals on the American side together with basic intrusives and extrusives that we do not have in northern Europe, but are found in southwest France, Spain and Morocco. I am particularly fond or" a picture I took in the Anti-Atlas of Morocco of such a lava flow in Triassic red beds with a donkey as a scale in the foreground. In fact it may be significant that the last lava flow in Morocco (and small boys selling amethyst) are a good indicato~ of the top of the Trias. Along with obvious growth faults, they would seem to confirm the classic view of these as simple extensional basins, but the papers herein maintain that they involve wrench tectonics, successor basins and listric faulting. The red beds in the Newark Supergroup on the eastern margin of North America are remarkably like those on the western margin of Europe and Africa, but one could extend the comparison from the Moenkopi Formation of Arizona to the Black Forest and beyond. So it is not just a matter of tension and continental breakup. The tragedy of the eastern margin of North America, in my prejudiced opinion, is the absence of the Lower Jurassic strata north of Mexico although they are so richly developed in Europe and northwest Africa. This problem is not discussed here, though evaporites are recorded off-shore which have doubtfully (in my opinion) been attributed to this age and it has even been suggested that ,the whole North Atlantic was a salt basin in Early Jurassic times. I do not find this an acceptable hypothesis. These volumes are al~aost entirely about the North Atlantic and the southern part of the ocean hardly gets a look-in. It is a pity in that connection that the authors did not include more about the Cretaceous which is only mentioned in two papers. The Cretaceous in a way completes the Atlantic story (including the carbonaceous deposits in the south), though the main opening came later. Again there is a remarkable parallelism between the