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Light and photosynthesis in aquatic ecosystems
362
Overall, I find the positive attributes of this review to outweigh the negative ones. Even though this review is a general t r e a t m e n t of the subject, anyone interested in water pollution and management will want to include this book as part of their reading. DAVID L. SUTTON University o f Florida -- I F A S Center for Aquatic Weeds Fort Lauderdale Research and Education Center 3205 College A v e n u e Fort Lauderdale, FL 33314, U.S.A.
LIGHT A N D A Q U A T I C E C O S Y S T E M S
Light and Photosynthesis in Aquatic Ecosystems. J o h n T.O. Kirk, Cambridge University Press, Cambridge/New York/Melbourne, 1983, xi + 401 pp., Price: £37.50/US $74.50, ISBN 0-521-24450-1. This book will be a valued addition to m y bookshelves and I have few hesitations in recommending it to experienced workers with an interest in the subjects of the title. As a plant physiologist, turned limnology teacher and aquatic plant researcher, I found, thankfully, that it contained little that was totally new to me in terms of the concepts or topics thought by the author to be relevant. Nevertheless, with its precise mathematical definitions of various aspects of the physics of light, provision of at least "lead-in" references to most specialist fields, and total coverage, it will be an invaluable one-volume source o f information on those many aspects one " k n o w s " , but only far too vaguely for c o m f o r t when certainty is needed. Thus, in m y view, it succeeds admirably in its objectives (author's preface) of being representative, rather than encyclopaedic, and communicating to limnologists and marine biologists a broad understanding of the significance of light as a major factor in aquatic ecosystems. Those with lesser experience of the topics will find the book to be difficult reading in places but, with persistence, should have few excuses for any further ignorance of most relevant aspects. There are 2 major sections: (I) labelled "The underwater light field"; (II) "Photosynthesis in the aquatic environment", followed by a reference list (30 pp. and 561 entries) and 3 indexes (Organisms, Subject, Water Bodies). Part I, broadly on the physics of light, has chapters on concepts of hydrological optics, incident solar radiation, absorption of light within the aquatic medium, scattering of light within the aquatic medium, characterizing the underwater light field. The nature of the underwater light field, and r e m o t e sensing of the aquatic environment. Part II, the biological interactions, has chapters on the photosynthetic apparatus of aquatic plants. Light capture by aquatic plants, photosynthesis as a function of the incident light, photosynthesis in the aquatic environment and ecological strategies.
363 The figures (line diagrams, graphs and photographs) are all appropriate to the text, well located, clear and "uncluttered"; in fact, many contributors to Aquatic Botany could use most as excellent examples to follow when submitting papers! Tables, also, are well selected and set out, although fewer in number, as one w o u l d expect from the intended concentration on principles rather than full detail. The legends, unfortunately, t o o often detract: some need to be more descriptive to adequately explain certain graphical presentations; others are far t o o long, mainly because of associated defining data which would have been better located in an adjacent table or in the text. I would also have w e l c o m e d a few more explanatory labels on some diagrams in Part I: the author uses only mathematical s y m b o l s and I lost visual simplicity in the need for constant reference to legend or text. The b o o k is very well produced and Cambridge University Press deserve our gratitude for their efforts, especially in the high quality reproduction of all the figures. Unfortunately, useful though this b o o k is to a University teacher with some knowledge of the field, it cannot be r e c o m m e n d e d as a text for undergraduates (admittedly, a group n o t included in the author's objectives). I have doubts, also, a b o u t its usefulness to a target group, research students, at least at the start of their independent efforts. So many, in these days of greater freedom in course selection, do n o t initially have the desirable background to make best use of its information. These strictures arise from 2 main criticisms: first, the rigid separation of physics and biology often requires the input of previous knowledge to appreciate fully the need for much of the subject matter. Indeed, the frequent references, backward and forward, to other chapters suggest that this was realised by the author. It creates difficulties for the biologist in the physical sections and for the physicist in the biological. Secondly, overall objectives are often obscured by the very rapid progression into more detail than might be expected for " b r o a d understanding" at less expert levels. The author does explain objectives, b u t far t o o briefly to set the scene in the absence of prior knowledge. More general, less mathematically rigid, introductory statements would have helped biologists in Part I, for example. Many (and I am still partly within that group) still struggle if plunged into precise equations before principles have been adequately grasped. In Part II, relatively detailed accounts of variation in pigment composition are separated from biological stratifications which might help to explain strategies associated with the light fields in water. I was also surprised, somewhat, by such things as descriptions of stroma and thylakoids before their biochemical specialisations were introduced. No one author attempting such a wide compass as this can reasonably be expected to get everything totally correct or to be fully up to date. Thus, RuBP is still R u D P (whence, then RUBISCO?) and 2ATP are shown as produced in the light reactions by a summary equation immediately above the carbon equation showing 3ATP consumed. I searched for, b u t could not find, "cyclic p h o t o p h o s p h o r y l a t i o n " in the text (brief mention was made in
364 a diagram). More serious a mistake, perhaps, is the bald statement that starch accumulates in the chloroplast -- in higher plants, at least, modern views of the dynamics of photosynthesis suggest t h a t this leads to reductions in rate, and thus, that the chloroplast is not the major storage organelle for photosynthetically produced starch, except under certain "stress" conditions. A major omission from the book, in Parts I and II, is any real consideration of short-term light fluctuations as a significant factor in the photosynthetic responses of aquatic plants. Numerous papers have appeared in the last few years on this topic. As joint chief editor of this journal I was also disappointed that the author did not more clearly set out the units which should be used in describing light and its biological interactions. All are there but sufficiently submerged in the other details to allow the present disagreements between reviewers and authors to continue. Thankfully, to me at least, " p h o t o fluence r a t e " appeared to be absent. Despite these criticisms, I still rate this as an excellent book and as one strongly recommended as w o r t h y of purchase. This is evidenced by the fact t h a t my review copy has often been difficult to hold o n t o against the claims of colleagues and senior research students who wished to look at specific chapters. J.M.A. BROWN Senior Lecturer in Botany The University of Auckland Private Bag Auckland New Zealand
OXYGEN SENSORS Polarographic Oxygen Sensors: A q u a t i c and Physiological Applications. E. Gnaiger and H. Forstner {Editors), Springer Verlag, Berlin/Heidelberg/ New York, 1983, xii + 370 pp., 142 figs., Price: DM 118, approx. US $50.90. ISBN 3-540-11654-0.
In his preface Dr Gnaiger states, inter alia, " Ideas and technological advances in one field may unexpectedly provide the key to solving problems in other apparently unrelated disciplines .... Thus, perhaps even those readers whose special knowledge or special needs are neglected or inadequately dealt with may find some inspiration." One's view of this volume depends on reactions to this statement. On the basis of papers submitted to Aquatic Botany, I suspect t h a t most of the readership will fall into the " n e g l e c t e d " category; how far "inspiration" or a desire to be more erudite about instrumental facets will counterbalance this is hard to assess. Personally, I am pleased to have this volume available as a reference t e x t for those unexpected experi-
Overall, I find the positive attributes of this review to outweigh the negative ones. Even though this review is a general t r e a t m e n t of the subject, anyone interested in water pollution and management will want to include this book as part of their reading. DAVID L. SUTTON University o f Florida -- I F A S Center for Aquatic Weeds Fort Lauderdale Research and Education Center 3205 College A v e n u e Fort Lauderdale, FL 33314, U.S.A.
LIGHT A N D A Q U A T I C E C O S Y S T E M S
Light and Photosynthesis in Aquatic Ecosystems. J o h n T.O. Kirk, Cambridge University Press, Cambridge/New York/Melbourne, 1983, xi + 401 pp., Price: £37.50/US $74.50, ISBN 0-521-24450-1. This book will be a valued addition to m y bookshelves and I have few hesitations in recommending it to experienced workers with an interest in the subjects of the title. As a plant physiologist, turned limnology teacher and aquatic plant researcher, I found, thankfully, that it contained little that was totally new to me in terms of the concepts or topics thought by the author to be relevant. Nevertheless, with its precise mathematical definitions of various aspects of the physics of light, provision of at least "lead-in" references to most specialist fields, and total coverage, it will be an invaluable one-volume source o f information on those many aspects one " k n o w s " , but only far too vaguely for c o m f o r t when certainty is needed. Thus, in m y view, it succeeds admirably in its objectives (author's preface) of being representative, rather than encyclopaedic, and communicating to limnologists and marine biologists a broad understanding of the significance of light as a major factor in aquatic ecosystems. Those with lesser experience of the topics will find the book to be difficult reading in places but, with persistence, should have few excuses for any further ignorance of most relevant aspects. There are 2 major sections: (I) labelled "The underwater light field"; (II) "Photosynthesis in the aquatic environment", followed by a reference list (30 pp. and 561 entries) and 3 indexes (Organisms, Subject, Water Bodies). Part I, broadly on the physics of light, has chapters on concepts of hydrological optics, incident solar radiation, absorption of light within the aquatic medium, scattering of light within the aquatic medium, characterizing the underwater light field. The nature of the underwater light field, and r e m o t e sensing of the aquatic environment. Part II, the biological interactions, has chapters on the photosynthetic apparatus of aquatic plants. Light capture by aquatic plants, photosynthesis as a function of the incident light, photosynthesis in the aquatic environment and ecological strategies.
363 The figures (line diagrams, graphs and photographs) are all appropriate to the text, well located, clear and "uncluttered"; in fact, many contributors to Aquatic Botany could use most as excellent examples to follow when submitting papers! Tables, also, are well selected and set out, although fewer in number, as one w o u l d expect from the intended concentration on principles rather than full detail. The legends, unfortunately, t o o often detract: some need to be more descriptive to adequately explain certain graphical presentations; others are far t o o long, mainly because of associated defining data which would have been better located in an adjacent table or in the text. I would also have w e l c o m e d a few more explanatory labels on some diagrams in Part I: the author uses only mathematical s y m b o l s and I lost visual simplicity in the need for constant reference to legend or text. The b o o k is very well produced and Cambridge University Press deserve our gratitude for their efforts, especially in the high quality reproduction of all the figures. Unfortunately, useful though this b o o k is to a University teacher with some knowledge of the field, it cannot be r e c o m m e n d e d as a text for undergraduates (admittedly, a group n o t included in the author's objectives). I have doubts, also, a b o u t its usefulness to a target group, research students, at least at the start of their independent efforts. So many, in these days of greater freedom in course selection, do n o t initially have the desirable background to make best use of its information. These strictures arise from 2 main criticisms: first, the rigid separation of physics and biology often requires the input of previous knowledge to appreciate fully the need for much of the subject matter. Indeed, the frequent references, backward and forward, to other chapters suggest that this was realised by the author. It creates difficulties for the biologist in the physical sections and for the physicist in the biological. Secondly, overall objectives are often obscured by the very rapid progression into more detail than might be expected for " b r o a d understanding" at less expert levels. The author does explain objectives, b u t far t o o briefly to set the scene in the absence of prior knowledge. More general, less mathematically rigid, introductory statements would have helped biologists in Part I, for example. Many (and I am still partly within that group) still struggle if plunged into precise equations before principles have been adequately grasped. In Part II, relatively detailed accounts of variation in pigment composition are separated from biological stratifications which might help to explain strategies associated with the light fields in water. I was also surprised, somewhat, by such things as descriptions of stroma and thylakoids before their biochemical specialisations were introduced. No one author attempting such a wide compass as this can reasonably be expected to get everything totally correct or to be fully up to date. Thus, RuBP is still R u D P (whence, then RUBISCO?) and 2ATP are shown as produced in the light reactions by a summary equation immediately above the carbon equation showing 3ATP consumed. I searched for, b u t could not find, "cyclic p h o t o p h o s p h o r y l a t i o n " in the text (brief mention was made in
364 a diagram). More serious a mistake, perhaps, is the bald statement that starch accumulates in the chloroplast -- in higher plants, at least, modern views of the dynamics of photosynthesis suggest t h a t this leads to reductions in rate, and thus, that the chloroplast is not the major storage organelle for photosynthetically produced starch, except under certain "stress" conditions. A major omission from the book, in Parts I and II, is any real consideration of short-term light fluctuations as a significant factor in the photosynthetic responses of aquatic plants. Numerous papers have appeared in the last few years on this topic. As joint chief editor of this journal I was also disappointed that the author did not more clearly set out the units which should be used in describing light and its biological interactions. All are there but sufficiently submerged in the other details to allow the present disagreements between reviewers and authors to continue. Thankfully, to me at least, " p h o t o fluence r a t e " appeared to be absent. Despite these criticisms, I still rate this as an excellent book and as one strongly recommended as w o r t h y of purchase. This is evidenced by the fact t h a t my review copy has often been difficult to hold o n t o against the claims of colleagues and senior research students who wished to look at specific chapters. J.M.A. BROWN Senior Lecturer in Botany The University of Auckland Private Bag Auckland New Zealand
OXYGEN SENSORS Polarographic Oxygen Sensors: A q u a t i c and Physiological Applications. E. Gnaiger and H. Forstner {Editors), Springer Verlag, Berlin/Heidelberg/ New York, 1983, xii + 370 pp., 142 figs., Price: DM 118, approx. US $50.90. ISBN 3-540-11654-0.
In his preface Dr Gnaiger states, inter alia, " Ideas and technological advances in one field may unexpectedly provide the key to solving problems in other apparently unrelated disciplines .... Thus, perhaps even those readers whose special knowledge or special needs are neglected or inadequately dealt with may find some inspiration." One's view of this volume depends on reactions to this statement. On the basis of papers submitted to Aquatic Botany, I suspect t h a t most of the readership will fall into the " n e g l e c t e d " category; how far "inspiration" or a desire to be more erudite about instrumental facets will counterbalance this is hard to assess. Personally, I am pleased to have this volume available as a reference t e x t for those unexpected experi-