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Algae as ecological indicators
289 result in considerable direct physical effects from blast, thermal radiation, and local fallout; lethal levels of radiation from local fallout would extend hundreds of kilometers downwind - - nor about the famine in Ethiopia. These are facts. On the o t he r hand, there is no substantial reason to believe t hat a major n u clear war could lead to large-scale climatic perturbations involving drastic reductions in light levels and temperatures over large regions within days, and changes in precipitation patterns for periods of days, weeks, months or longer, or th at such episodes could produce serious impacts if they occur during critical periods within the growing season. There is scarcely a more sensitive growing season indicator t h a n wine. Major volcanic eruptions injected into the atmosphere at each event the same order of magnitude of dust (page 216 of Vol. I puts this mass at 100 million tonne = 100Tg; about 30Tg have been estimated for K r akat oa, 1883). The wine harvest of the last two centuries contains no indication of a volcanic signal (M. Benarie, The Science of the Total Environment, 50 (1986) 191-196). Remembering Sir K.R. Popper, the wine/volcano experiment effectively falsifies the pyramid of hypotheses onto which the nuclear winter scenario has been so carefully erected. Lydia Dotto's book is based on these SCOPE reports. It is a readable popularization of the contents of the main report, thus making an even better, more popular decoy for those who prefer shuddering before remote scenarios instead of opening their eyes to what happens in the world now.
Bretigny-sur-Orge (France)
Michel Benarie
Algae as Ecological Indicators, edited by L.E. Shubert, Academic Press, London, 1984, 434 pp. Price: £43.50. This book is not, necessarily, what it might at first appear to be from its title: it is not a book simply about the role of algae in indicating environmental co n cen tr ati ons of chemicals, for instance, nor on their use in the wider monitoring sense. Indeed there is little mention made of the larger benthic algae which are most commonly used for such excercises. Instead it is a compilation of papers - - arising from a symposium of the same title held in Oklahoma State University back in 1979 - - which attempts to summarise recent developments in the use of algal bioassays as indicators of ecological change. But change in what? It is the answer to this question which ultimately alludes many of the authors. There are six sections. Three papers discuss the freshwater environment with p h y t o p l a n k t o n i c assemblages being used in a variety of techniques, from assay procedures to evaluate 'water quality', to the large in situ enclosures employed in CEPEX (controlled ecosystem pollution experiment) studies. All are strong on techniques but short on results. But at least some degree of standardisation has been achieved, which is more t han can be said of parallel
290 studies in the marine field. These have been excellently summarised in two chapters by Maestrini et al. and relate essentially to experiments which have been carried out to determine the factors which may or may not be effective in controlling primary production and population succession. But one gets the impression t h a t algae are obviously indicators of their own populations but not necessarily of anyt hi ng else. A third paper, on seaweeds, completes the marine section by discussing the possibility of using cell division and elongation of macro-algae as a bioassay test, together with a sketchy summary of t h e u s e of seaweeds as 'bioaccumulators of pollutants' which is too superficial to be of value. The use of algae as indicators of soil fertility is the somewhat unexpected subject of the only contribution to the next section. Not surprisingly it concludes th at more research is required before a more succinct commentary on the utility of such an approach is likely to be forthcoming, but the soil diatom Hantzschia appears to offer potential. It is not, therefore, until the fourth section t h a t the book really arrives at what one would consider to be its main objective: the i nt er a c t i on between algae and toxic substances, heavy metals and vitamins. From the papers on these topics one concludes t hat different species vary widely in their response to toxic chemicals, and t hat they are not particularly useful in freshwater situations as monitors of heavy metals nor of vitamins, given the present state of knowledge and expertise. So are there any industrial applications of such techniques? Two papers - - again heavy on methodology, much of it repetative of earlier sections - - but light on application, do not inspire confidence of a more widespread usage of unicellular algae other th an as general indicators of, again, 'water quality'. The book then concludes with a further two papers on the subject of modelling. T h r o u g h o u t the book one is impressed by the enthusiasm of the authors, and one is led to conclude undeniably t h a t phytoplanktonic cultures can be used to detect changes in the undefinable 'quality of water', whatever t hat may be. But one is also led to conclude t hat what the bioassays indicate is whether or not the water under test is conducive to the well being of the species of alga being used but not necessarily of anything else. There is no evaluation of such 'bio' techniques in comparison with straightforward chemical analyses for a range of possible contaminants, and one suspects t hat if such a comparison were to be made the bioassay method would not begin to compete.
Lowestoft (United Kingdom)
R.J. P e n t r e a t h
Pollutants and Their Ecotoxicological Significance, edited by H.W. Nfirnberg, J o h n Wiley & Sons, Chichester, 1985, 515 pp. Price: £49.50. The general c ont a m i nat i on of the n a t u r a l environment with chemicals has now become such a large and complicated subject t hat it is difficult for a
Bretigny-sur-Orge (France)
Michel Benarie
Algae as Ecological Indicators, edited by L.E. Shubert, Academic Press, London, 1984, 434 pp. Price: £43.50. This book is not, necessarily, what it might at first appear to be from its title: it is not a book simply about the role of algae in indicating environmental co n cen tr ati ons of chemicals, for instance, nor on their use in the wider monitoring sense. Indeed there is little mention made of the larger benthic algae which are most commonly used for such excercises. Instead it is a compilation of papers - - arising from a symposium of the same title held in Oklahoma State University back in 1979 - - which attempts to summarise recent developments in the use of algal bioassays as indicators of ecological change. But change in what? It is the answer to this question which ultimately alludes many of the authors. There are six sections. Three papers discuss the freshwater environment with p h y t o p l a n k t o n i c assemblages being used in a variety of techniques, from assay procedures to evaluate 'water quality', to the large in situ enclosures employed in CEPEX (controlled ecosystem pollution experiment) studies. All are strong on techniques but short on results. But at least some degree of standardisation has been achieved, which is more t han can be said of parallel
290 studies in the marine field. These have been excellently summarised in two chapters by Maestrini et al. and relate essentially to experiments which have been carried out to determine the factors which may or may not be effective in controlling primary production and population succession. But one gets the impression t h a t algae are obviously indicators of their own populations but not necessarily of anyt hi ng else. A third paper, on seaweeds, completes the marine section by discussing the possibility of using cell division and elongation of macro-algae as a bioassay test, together with a sketchy summary of t h e u s e of seaweeds as 'bioaccumulators of pollutants' which is too superficial to be of value. The use of algae as indicators of soil fertility is the somewhat unexpected subject of the only contribution to the next section. Not surprisingly it concludes th at more research is required before a more succinct commentary on the utility of such an approach is likely to be forthcoming, but the soil diatom Hantzschia appears to offer potential. It is not, therefore, until the fourth section t h a t the book really arrives at what one would consider to be its main objective: the i nt er a c t i on between algae and toxic substances, heavy metals and vitamins. From the papers on these topics one concludes t hat different species vary widely in their response to toxic chemicals, and t hat they are not particularly useful in freshwater situations as monitors of heavy metals nor of vitamins, given the present state of knowledge and expertise. So are there any industrial applications of such techniques? Two papers - - again heavy on methodology, much of it repetative of earlier sections - - but light on application, do not inspire confidence of a more widespread usage of unicellular algae other th an as general indicators of, again, 'water quality'. The book then concludes with a further two papers on the subject of modelling. T h r o u g h o u t the book one is impressed by the enthusiasm of the authors, and one is led to conclude undeniably t h a t phytoplanktonic cultures can be used to detect changes in the undefinable 'quality of water', whatever t hat may be. But one is also led to conclude t hat what the bioassays indicate is whether or not the water under test is conducive to the well being of the species of alga being used but not necessarily of anything else. There is no evaluation of such 'bio' techniques in comparison with straightforward chemical analyses for a range of possible contaminants, and one suspects t hat if such a comparison were to be made the bioassay method would not begin to compete.
Lowestoft (United Kingdom)
R.J. P e n t r e a t h
Pollutants and Their Ecotoxicological Significance, edited by H.W. Nfirnberg, J o h n Wiley & Sons, Chichester, 1985, 515 pp. Price: £49.50. The general c ont a m i nat i on of the n a t u r a l environment with chemicals has now become such a large and complicated subject t hat it is difficult for a