reaching its maximum, gradually decreases, large-scale pollution not 

 only does not decrease its intensity as long periods of time pass, but, 

 in terms of a number of its indices, is gradually increasing. This is 

 quite understandable if we consider the relative stability and the 

 increasing trend of the characteristics of world industrial production, 

 which correlate directly to the fluxes and levels of pollution of the 

 hydrosphere. 



1.3 Biologic and Ecologic Effects of Pollution . 



The basic difficulty which arises upon analysis of the effects of 

 anthropogenic changes in the chemical composition of the marine 

 environment results from the fact that living systems react to the 

 presence of toxic or other pollutant ingredients at the same time at all 

 levels of organization of life--from the subcellular to the 

 superorganismic. A complex mosaic of direct and indirect mechanisms and 

 manifestations of the effects of toxicants arises, against the 

 background of the natural dynamics of biologic processes. 



Various versions of systematization of biologic effects and 

 aftereffects of pollution of the marine environment are possible. In 

 the first approximation, it is desirable to differentiate two groups of 

 ecologic-toxicologic situations: direct toxic or stress effects on 

 separate populations and communities, accompanied by rapid damage to the 

 primary physiologic-biochemicl systems of organisms, with subsequent 

 lethal intoxication, elimination of individual species or clear 

 pathologic changes, and the effect of comparatively low concentrations 

 of pollutants on the organisms and communities upon long-term, chronic 

 pollution. The impressive, at times tragic, examples of situations of 

 the first kind, usually arising as a result of an accident or one-time 

 spill of industrial wastes, are well known (Fontaine, 1966; Mironov, 

 1972; Aubert, 1973). Fortunately, these areas of intensive pollution 

 are usually located within very limited zones in the sea and the results 

 of such events, even if quite severe, do not extend over broad areas of 

 water. The second group of effects is not so obvious, and has been much 

 less studied. Due to differences in the level of resistance of various 

 species and of various stages of ontogenesis of hydrobionts, a complex 

 chain of biologic reactions and responses arises in the community, the 

 final and most significant manifestation of which is a change in the 

 equilibrium and stability of the community. These changes may be 

 manifested as a decrease in the index of species variety (Bechtel , 

 Copeland, 1970), a disruption in the timing and relationship of 

 processes of production and destruction of organic matter (Kamshilov, 

 1968), anomalies of the dynamics of dissolved oxygen (Braginskii, 1972), 

 changes in dominant species in the biocenosis (Bellan, Bel lan-Santini , 

 1972) or other ecologic disruptions (Woodwell, 1970). 



The non-obvious nature of this type of result, in comparison to 

 acute intoxication (for example, massive fish kills) does not mean that 

 these consequences are any less serious or significant. The situation 

 is more probably the opposite, considering the scale and universality of 

 large-scale pollution, as well as its other aspects, noted above 

 (correlation with distribution of biologic productivity, constancy of 



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