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Interactions between air contaminants and forest ecosystems
187 taking place, i.e. the application of advanced physical theories (quantum theory, molecular dynamics, solid-state theories, etc.) to the single particle, or to a small number of particles. This volume is a significant contribution to this transition from phenomenological to physically rigorous work in the field of aerosol microphysics. It includes reviews of the physics of microparticles and aerosol growth by condensation, as well as discussions of c o m p u t e r modelling of heterogeneous systems and of the electronic structure of chemisorbed overlayers on surfaces and clusters. Aerosol microphysics I has been reviewed in Vol. 25, pp. 94--95 of this journal. The same rigour, the same very high standard o f the physico-mathematical treatment, and the same good presentation, characterize this volume too. Bretign y (France)
Michel Benarie
Interactions between Air Contaminants and Forest Ecosystems by W.H. Smith, Springer-Verlag, Berlin (Springer Series on Environmental Management, Ed: R.S. DeSanto) 1981, 379 pp. Price: cloth DM 64,00 (approx US$ 30.50). Professor Smith, in an original way, divides the interactions between air pollutants and forest ecosystem into three classes. In Class I relationships (conditions of low doses), pollutants would be exchanged between the atmospheric compartments and various elements of the biota. Depending on the nature of the pollutant, the ecosystem impact of this transfer could be undetectable (innocuous effect) or stimulatory (fertilizing effect). Under conditions of low dose, the vegetation and soils of forest ecosystems function as important sources and sinks of air pollution. To mention "source" in this c o n t e x t may surprise some non-specialists, but forests produce globally a b o u t as much carbon monoxide as comes from the exhausts of m o t o r vehicles all over the world, they produce a b o u t 400 times more organic and inorganic sulphur volatiles SO2 included, than all human activities; they produce a b o u t seven times more reactive hydrocarbons than man does, and so on (p. 120 of the book). At intermediate doses (Class II relationships), the effect of air pollution on some c o m p o n e n t m a y be inimical. Individual tree species or individual members of a given species may be subtly and adversly affected by nutrient stress, impaired metabolism, predisposition to entomological or pathological stress, or direct disease induction. Exposure to high doses (Class III relationships) may induce morbidity or mortality in an acute way. Specific trees may be impaired through changes in energy flow and biogeochemical cycling, changes in hydrology and erosion, climate alteration and major impacts on associated ecosystems. While these classes of interaction are conceptually right and didactically useful, they suffer from the weakness that the experimental data so far available allow one only in exceptional cases to distinguish between the
188 threshold concentrations among the classes in general, and, in particular, between Class I and II relationships. To q u o t e the author (p. 305): "Perhaps the most disappointing aspect of sulphur dioxide studies is infrequent presentation of dose information. Ambient concentrations and exposure durations were rarely monitored or reported. For historical studies it is clearly frequently impossible to provide this information. For contemporary investigations, however, inclusion of this information would greatly increase the utility of the data". In other words, while the effects are well known, we are still ignorant of the damage functions, which are the core of the problem. Without quantitative relationships, air pollution " d a m a g e " is a fuzzy belief and n o t an economic-~scientific fact. Class III, where the damage is heavy and the s y m p t o m s are visible, is perhaps the easiest to discuss. The other end of the scale, where there is no effect, as for example acid rain, is also relatively simple: "The possibility of enhanced cation availability in, or loss from, soils due to increased weathering of parent soil materials by hydrogen ions from acid precipitation is n o t supported by evidence presently available" (p. 188), and "The authors concluded that no clear effects of acid precipitation on diameter growth of spruce and pine were detected by regional tree-ring analyses" (p. 306); and further: "Cogbill concluded that no correlation of forest growth and acid rain could be established for eastern North America" (p. 307). This volume contains a comprehensive synthesis and overview of what is so far known about the interactions between atmospheric pollutants and forest ecosystems. At least as valuable is the fact that the author points n o t only at the emerging tip of the iceberg represented by the established facts, b u t also to the larger submerged part, the still u n k n o w n and uncertain part. Taking into account that the literature review for the b o o k was completed in January 1980, it is nevertheless surprising that Stren's widely known "Air Pollution" is quoted only as its one-volume 1973 edition (pp. 54, 295). In the meantime, rapid progress in the field has justified first a three-volume second, then a five-volume third edition.
Bretign y (France)
Michel Benarie
Michel Benarie
Interactions between Air Contaminants and Forest Ecosystems by W.H. Smith, Springer-Verlag, Berlin (Springer Series on Environmental Management, Ed: R.S. DeSanto) 1981, 379 pp. Price: cloth DM 64,00 (approx US$ 30.50). Professor Smith, in an original way, divides the interactions between air pollutants and forest ecosystem into three classes. In Class I relationships (conditions of low doses), pollutants would be exchanged between the atmospheric compartments and various elements of the biota. Depending on the nature of the pollutant, the ecosystem impact of this transfer could be undetectable (innocuous effect) or stimulatory (fertilizing effect). Under conditions of low dose, the vegetation and soils of forest ecosystems function as important sources and sinks of air pollution. To mention "source" in this c o n t e x t may surprise some non-specialists, but forests produce globally a b o u t as much carbon monoxide as comes from the exhausts of m o t o r vehicles all over the world, they produce a b o u t 400 times more organic and inorganic sulphur volatiles SO2 included, than all human activities; they produce a b o u t seven times more reactive hydrocarbons than man does, and so on (p. 120 of the book). At intermediate doses (Class II relationships), the effect of air pollution on some c o m p o n e n t m a y be inimical. Individual tree species or individual members of a given species may be subtly and adversly affected by nutrient stress, impaired metabolism, predisposition to entomological or pathological stress, or direct disease induction. Exposure to high doses (Class III relationships) may induce morbidity or mortality in an acute way. Specific trees may be impaired through changes in energy flow and biogeochemical cycling, changes in hydrology and erosion, climate alteration and major impacts on associated ecosystems. While these classes of interaction are conceptually right and didactically useful, they suffer from the weakness that the experimental data so far available allow one only in exceptional cases to distinguish between the
188 threshold concentrations among the classes in general, and, in particular, between Class I and II relationships. To q u o t e the author (p. 305): "Perhaps the most disappointing aspect of sulphur dioxide studies is infrequent presentation of dose information. Ambient concentrations and exposure durations were rarely monitored or reported. For historical studies it is clearly frequently impossible to provide this information. For contemporary investigations, however, inclusion of this information would greatly increase the utility of the data". In other words, while the effects are well known, we are still ignorant of the damage functions, which are the core of the problem. Without quantitative relationships, air pollution " d a m a g e " is a fuzzy belief and n o t an economic-~scientific fact. Class III, where the damage is heavy and the s y m p t o m s are visible, is perhaps the easiest to discuss. The other end of the scale, where there is no effect, as for example acid rain, is also relatively simple: "The possibility of enhanced cation availability in, or loss from, soils due to increased weathering of parent soil materials by hydrogen ions from acid precipitation is n o t supported by evidence presently available" (p. 188), and "The authors concluded that no clear effects of acid precipitation on diameter growth of spruce and pine were detected by regional tree-ring analyses" (p. 306); and further: "Cogbill concluded that no correlation of forest growth and acid rain could be established for eastern North America" (p. 307). This volume contains a comprehensive synthesis and overview of what is so far known about the interactions between atmospheric pollutants and forest ecosystems. At least as valuable is the fact that the author points n o t only at the emerging tip of the iceberg represented by the established facts, b u t also to the larger submerged part, the still u n k n o w n and uncertain part. Taking into account that the literature review for the b o o k was completed in January 1980, it is nevertheless surprising that Stren's widely known "Air Pollution" is quoted only as its one-volume 1973 edition (pp. 54, 295). In the meantime, rapid progress in the field has justified first a three-volume second, then a five-volume third edition.
Bretign y (France)
Michel Benarie