Atmosphere-Biosphere Interactions Toward a Better Understanding of the Ecological Consequences of Fossil Fuel Combustion (1981) / Chapter Skim
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7 Studying the Effects of Atmospheric Deposition on Ecosystems
7 Studying the Effects of Atmospheric Deposition on Ecosystems
Pages 119-139
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From page 119... ...
Epizootics of benign skin tumors (papillomas) were found in white sucker, Catastomas commersoni populations throughout the Great Lakes.
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From page 120... ...
Alternatively, some sulfate in anaerobic habitats may be reduced to volatile sulfides, and some nitrate to gaseous ammonia, which return to the atmosphere, where the sulfides may again be oxidized and interact with ammonia to form ammonium sulfate aerosols. Metals such as lead, which often accompany sulfate in particulate pollution, will follow yet another path, becoming strongly adsorbed to ion-exchange sites on soil clays or humic acids.
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From page 121... ...
PREDICTING ANTHROPOGENIC EFFECTS ON ECOSYSTEMS Separating human-induced ecological changes from natural ones and measuring them is not a simple matter, particularly when the changes occur slowly. In describing such changes and in establishing causality, there is often an implicit assumption that in the absence of human intervention ecosystems are in some sort of distinguishable and predictable successional state.
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From page 122... ...
Let us review, then, the types of information necessary for predicting the biological effects of atmospheric deposition. · For predictive purposes, one would like to know which source characteristics and emission processes govern the various substances emitted, their forms and properties, and their rates of emission.
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From page 123... ...
(W) 1~:' I Waters ~;;1 Em ission Concen trat ion at Point Emission Amount Em itted Over Unit Time = Transport ~ Rate of Transport \/ diffusion 4;vironmental)
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From page 124... ...
1980~; both are components of coal combustion products. It is also noteworthy that the NOX contribution to acid precipitation may supply both a limiting nutrient, nitrogen, and a potential toxicant, hydrogen ions, to receptor ecosystems, with the nutrient contribution likely to be more important in the short run and the acidifying component more significant over the long term (Tamm 1976, Abrahamsen 1980~.
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From page 125... ...
Information on distribution and abundance of sensitive receptors and distribution and size of pollutant sources is important for determining the effect of a particular pollutant upon a particular ecosystem. A maximum effect could be expected in a situation in which the receptor species is highly sensitive to a particular pollutant, the species is rare but ecologically important, and either the sources and receptors are located together or the pollutant has a long atmospheric residence time.
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From page 126... ...
4. Residence times (up to days, weeks, months, longer)
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From page 127... ...
Economic (metals, other structural materials, fabrics, other organic materials)
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From page 128... ...
have used the feather moss Hylocomium splendens for assessing lead loadings near highways in Sweden, and for examining north-south latitudinal gradients. Cesium residence times in mats of Cladonia lichens were found to range from 4 to 25 years (Liden and Gustafsson 1967~.
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From page 129... ...
and heavy metals (Ruhling and Tyler 1971) , and a global "mussel watch" is now monitoring the dispersal of dangerous contaminants (such as organochlorides, trace metals, petroleum hydrocarbons, and transuranic elements)
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From page 130... ...
Bryophytes and lichens are especially tolerant of a number of these stresses -- e.g., cold, wind, and radiation -- but, as we have seen, where the stress involves entry of a pollutant into cell walls, the absence of a cuticle is a crucial disadvantage. Lichens and mosses generally are susceptible to atmospheric pollutants, such as SO2, fluorine, and trace metals, which are absorbed on the exposed surfaces.
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From page 131... ...
Cycle linkages may be of considerable importance in determining the total effect of air pollution upon a given organism and the ecosystem in which it occurs. For example, acid rain has both direct and indirect effects on fish; directly by toxicity of the hydrogen ion and indirectly by the mobilization of aluminum from soils.
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From page 132... ...
Results from existing studies concerning the fate and ecological effects of anthropogenic pollutants show that the toxicity of trace metals to marine organisms is related to both concentration and chemical speciation (Steemann and Wium-Andersen 1970, Harriss et al. 1970, Allen et al.
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From page 133... ...
MONI TORI NG LARGE- SCALE POLLUT ION No area of the United States or indeed of our planet is free from the effects of air pollution. Acid precipitation is slowly eroding the environmental quality of remote wilderness areas in northeastern
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From page 134... ...
Copyright ~ 1981 by the American Chemical Society.
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From page 135... ...
Copyright 0 1981 by the American Chemical Society.
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From page 136... ...
The international system of biosphere reserves (Risser and Cornelison 1979) could provide suitable sites for baseline monitoring, and the proposed national network of experimental ecological reserves (TIE 1977)
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From page 137... ...
Excess Vanadium I\ (nanograms per cubic meter) \ i' Ny/ 1 1 1 1 1 1 1 1 1 1 1 1 O N D J F M A M J J A S FIGURE 7.4 Monthly mean concentrations at Barrow, Alaska, of atmospheric sulfate and vanadium that could not be attributed to natural processes.
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From page 138... ...
The data points, from three stations in the Savjann River, show the yearly periodic swings, and the arrow shows the average pH value.
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From page 139... ...
For the prediction of effect it is important to know the distribution and abundance of sensitive receptors, the distribution and size of emission sources, and the properties of the pollutant that govern residence times in various ecosystem compartments. Sensitivity of organisms and ecosystems to pollutant stress may be caused by a wide variety of receptor properties, and may vary with the nature of the pollutant and the stage of development of the organism or ecosystem.
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