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Electricity generation and the ecology of natural waters
3-~
Book Re;ie;~s
Electricity G e n c r l t i ~ and tile F_,edogy of Natural ~'sters, b~ T. E. L~.xc, m a v . Liverpool University Press. England. 1¢~83. 342 pp. £14.50 This pleasantly written and well-illustrated paperback draws on the author's own experience and a v e r , , useful compilation of nearly 1200 references. The nine chapters are each clearly and Iomcatly divided, with concluding summaries, so that within minutes of first opening the book one can choose to turn to the final conclusions and read that natural waters have been tar more affected by dams, diversions and lake control schemes than b) nuclear, coal- or oil-fired power stations. In some of the diagrams there is a mixture of m e m c and imperial units and in a few the description is inadequate. While the author uses the term "'s,,nergism'" correctly iand not in the looser manner c o m m o n i,a aquatic toxico!ogy as "'greater than additive toxicity") he misuses ' t o x i n " as a synonym t\~r "poison" rather than as a poisonous substance originating from a living organism. Apart from these minor points the text is almost free of errors. Tile scene is set with an account of the hundrcd-,,ear history of electricity generation, always involving water as a source of energy or for cooling. The awakening of ecological concern is traced and the variety of discharges from thermal power stations is d e m o n s t r a t e d Chapters 2 and 3 consider the physical and chemical consequences of power generation, the physical a s p ~ t s being divided between effects on the movement and temperature of the water. There is a lull discussion on dissolved gases followed by other chemical details, including the discharge of toxic wastes. After necessarily brief descriptions of the natural attributes and requirements of taxonomic groups (bacteria, fungi and p r o t o z o a - - a l g a e - - - m a c r o p h y t e s - - z o o p l a n k t o n - benthic macro-invertebrates--fishes), there is a thorough review of the considerable erects of hydro-electricity generation. The section on fishes forms the major part of this chapter. Having described normal temperature relationships, site studies are drawn on to demonstrate that permanent changes to ecosystems receiving thermal discharges are rarely due to added heat alone, perhaps because unlike the effects caused by dams, temperature effects may be transient, avoided or tolerated by adaptation. Organisms can have costly effects on power generation, such as the clogging of intakes to turbines and cooling systems. Physical, mechanical and chemical methods for
h m m n g the problems are dt~cussed. The trapping of ii~h on intake screens ~riousi? endangers certain p,-~pu~.~'~,~r',,5at ensuring that fiov,s at the screen are gentle .~ad r,u~hi: horizontal can help considerabk~ Chlorma~.:~a ,. ~t~ii "he cheapest and best anti-fouling method although ~t ~eads ~.c, mortality of entrained individuals and to e~uer~ pr,~bi¢.,::s These last are considered next, with the eflect-~ of a,h. hea,,~. metals, oil !minor). acid or alkaline waste~..iunospherJc emissions and radio-nuclides. It is concluded 'hat cn!~ chlorine is cleari? of major significance. ' A c i d r ~ m had not attracted the attentmn of the media untd after the book ',~a~ written, Had it done so perhaps the section on amlospheric emissions would have been enlarged from ~ts present three pages, which nevertheless mention most of the current arguments without going deeply into the exacerbating and complicating effects of. for example, coniferous forestr~ The changes caused by power stations are a,,, ~,i1 d e m mental. Commercial and recreational fishing rna? be c~haneed but the use of waste heat in aquac~Hture and horticulture is limited, although in its infant,. Nutura]!>. benefits onl> partially counterbalance environmental damage : building a dam may create a fishery hut prc~ents Hlc advantageous deposition of silt on the flood pLitn downstream.
Finally, legal aspects are touched on--fisher? protecuon (where d a m s obstruct migratJont---mimmum tlov, and patterns of flow--consent conditions for the discharge ot effluents from thermal, including nuclear, stations. The author is opposed to blanket limitation of temperature change, as recommended in the U.S,A and ~mposed m the EEC, preferring, laudably, to see individual circumstances individually handled. Similarly. a discussion of environmental impact statements concludes with a warmng of hov, wasteful in .scientific effort such legislation can become. Before s u m m i n g up, three notable legal acnons are described and a prediction made of future developments m power generation and in research needs. As l:ar as alternative sources of energy are concerned some telhng figures are given : 2000 M W - 130 km" o f solar power cells in the U.K.: one or two power stations - a,000 large windmills. It seems that water and power generation are going to be intimatelx linked for decades yet. T h e book will serve both as an introduction to the subject. tbr the university student, and as a distillation of the world's literature (and a valuable compendium o f references~ for the practising environmental scientist_ J. F SOLB~
Book Re;ie;~s
Electricity G e n c r l t i ~ and tile F_,edogy of Natural ~'sters, b~ T. E. L~.xc, m a v . Liverpool University Press. England. 1¢~83. 342 pp. £14.50 This pleasantly written and well-illustrated paperback draws on the author's own experience and a v e r , , useful compilation of nearly 1200 references. The nine chapters are each clearly and Iomcatly divided, with concluding summaries, so that within minutes of first opening the book one can choose to turn to the final conclusions and read that natural waters have been tar more affected by dams, diversions and lake control schemes than b) nuclear, coal- or oil-fired power stations. In some of the diagrams there is a mixture of m e m c and imperial units and in a few the description is inadequate. While the author uses the term "'s,,nergism'" correctly iand not in the looser manner c o m m o n i,a aquatic toxico!ogy as "'greater than additive toxicity") he misuses ' t o x i n " as a synonym t\~r "poison" rather than as a poisonous substance originating from a living organism. Apart from these minor points the text is almost free of errors. Tile scene is set with an account of the hundrcd-,,ear history of electricity generation, always involving water as a source of energy or for cooling. The awakening of ecological concern is traced and the variety of discharges from thermal power stations is d e m o n s t r a t e d Chapters 2 and 3 consider the physical and chemical consequences of power generation, the physical a s p ~ t s being divided between effects on the movement and temperature of the water. There is a lull discussion on dissolved gases followed by other chemical details, including the discharge of toxic wastes. After necessarily brief descriptions of the natural attributes and requirements of taxonomic groups (bacteria, fungi and p r o t o z o a - - a l g a e - - - m a c r o p h y t e s - - z o o p l a n k t o n - benthic macro-invertebrates--fishes), there is a thorough review of the considerable erects of hydro-electricity generation. The section on fishes forms the major part of this chapter. Having described normal temperature relationships, site studies are drawn on to demonstrate that permanent changes to ecosystems receiving thermal discharges are rarely due to added heat alone, perhaps because unlike the effects caused by dams, temperature effects may be transient, avoided or tolerated by adaptation. Organisms can have costly effects on power generation, such as the clogging of intakes to turbines and cooling systems. Physical, mechanical and chemical methods for
h m m n g the problems are dt~cussed. The trapping of ii~h on intake screens ~riousi? endangers certain p,-~pu~.~'~,~r',,5at ensuring that fiov,s at the screen are gentle .~ad r,u~hi: horizontal can help considerabk~ Chlorma~.:~a ,. ~t~ii "he cheapest and best anti-fouling method although ~t ~eads ~.c, mortality of entrained individuals and to e~uer~ pr,~bi¢.,::s These last are considered next, with the eflect-~ of a,h. hea,,~. metals, oil !minor). acid or alkaline waste~..iunospherJc emissions and radio-nuclides. It is concluded 'hat cn!~ chlorine is cleari? of major significance. ' A c i d r ~ m had not attracted the attentmn of the media untd after the book ',~a~ written, Had it done so perhaps the section on amlospheric emissions would have been enlarged from ~ts present three pages, which nevertheless mention most of the current arguments without going deeply into the exacerbating and complicating effects of. for example, coniferous forestr~ The changes caused by power stations are a,,, ~,i1 d e m mental. Commercial and recreational fishing rna? be c~haneed but the use of waste heat in aquac~Hture and horticulture is limited, although in its infant,. Nutura]!>. benefits onl> partially counterbalance environmental damage : building a dam may create a fishery hut prc~ents Hlc advantageous deposition of silt on the flood pLitn downstream.
Finally, legal aspects are touched on--fisher? protecuon (where d a m s obstruct migratJont---mimmum tlov, and patterns of flow--consent conditions for the discharge ot effluents from thermal, including nuclear, stations. The author is opposed to blanket limitation of temperature change, as recommended in the U.S,A and ~mposed m the EEC, preferring, laudably, to see individual circumstances individually handled. Similarly. a discussion of environmental impact statements concludes with a warmng of hov, wasteful in .scientific effort such legislation can become. Before s u m m i n g up, three notable legal acnons are described and a prediction made of future developments m power generation and in research needs. As l:ar as alternative sources of energy are concerned some telhng figures are given : 2000 M W - 130 km" o f solar power cells in the U.K.: one or two power stations - a,000 large windmills. It seems that water and power generation are going to be intimatelx linked for decades yet. T h e book will serve both as an introduction to the subject. tbr the university student, and as a distillation of the world's literature (and a valuable compendium o f references~ for the practising environmental scientist_ J. F SOLB~