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The results of a study on morphophysiological variation in fish inhabiting a subarctic lake exposed to chronic industrial pollution are described using an example of cisco, Coregonus lavaretus. It is shown that indices of the heart, liver, kidneys, gills, and fatness in these fish are increased significantly and have retained increased values for the past 20 years. The observed changes are analyzed on the basis of biochemical data. The results of studies on the dynamics of hematological parameters in fish are used for characterizing the development of toxicosis. Adaptive rearrangements associated with an increase in the metabolic rate and the activation of protective systems in the fish are explained in the context of S.S. Schvarts' concept. The idea is proposed that the additional energy cost of detoxification may be responsible for morphophysiological variation in fish under conditions of water pollution. 相似文献
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Disturbances in fish that result from water acidification and related factors are analyzed in the context of generalizations based on the results of experimental and field studies. It is shown that low pH, monomeric aluminum, and other metal ions have an adverse effect on physiological processes in fish and are a major cause of their death in acidified lakes and rivers. The vulnerability of fish to low water pH at different stages of their life cycle and mechanisms of delayed mortality are discussed. 相似文献
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Fish of a polymorphic and evolutionarily young species Coregonus lavaretusfrom a subarctic lake that has been polluted for more than 60 years are used as an example for analyzing principal trends in the dynamics of structural and functional organization of fish populations. It is shown that fish exposed to sublethal doses of toxic substances for a long time have a smaller body size, the period of their sexual maturation becomes more variable, and the frequency of spawning and life span decrease. The biochemical and bioenergetic mechanisms of variation in populations are analyzed. The ecological expediency of change in the life cycle strategy corresponding to r-selection (conversion to a short reproductive cycle) is substantiated. 相似文献
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T. I. Moiseenko 《Russian Journal of Ecology》2010,41(3):237-243
The effect of pollution on fish populations has been analyzed. It has been demonstrated that the strategy of the fish life
cycle changes in the direction corresponding to r-selection. Smaller individuals that mature at an earlier age and are preadapted to energy allocation for maintaining a higher
metabolic rate and activating detoxification gain a survival advantage under toxic conditions. If young females whose gametogenesis
is within the normal range join the spawning stock, the population size is successfully maintained but its parameters and
gene pool are changed. 相似文献
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T. I. Moiseenko 《Russian Journal of Ecology》2005,36(2):93-102
Effects of acidification on aquatic ecosystems are analyzed on the basis of an analytical synopsis of relevant data. Major active agents influencing aquatic organisms and main trends in the reorganization of microbial, phyto- and zooplanktonic, benthic, and fish communities in an acidified environment are described. A generalized concept of changes in ecosystems caused by acid precipitation and accompanying factors is formulated. These changes include the reduction of biodiversity of all structural elements due to the disappearance of species sensitive to acidification, modification of trophic structure, and decrease of fish stock.Translated from Ekologiya, No. 2, 2005, pp. 110–119.Original Russian Text Copyright © 2005 by Moiseenko. 相似文献
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T. I. Moiseenko 《Russian Journal of Ecology》2008,39(6):390-397
A methodological approach to water quality assessment within the scope of the ecosystem health concept is substantiated. Key tasks in water body pollution rating are specified. A rationale for the system of criteria for the diagnosis of aquatic ecosystem health is given on the basis of analysis of determinate changes in their organization levels under anthropogenic stress. The results of testing the proposed methods in water objects of the Volga basin and Lake Imandra are described. 相似文献
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Problems concerning microevolutionary transformations in animal populations are considered. It is shown that genetic variation
is the main factor providing the basis for adaptation to environmental changes, including toxic pollution. The selection pressure
of a toxic factor gives an advantage in survival to more resistant genotypes in animal populations, which eventually leads
to the reduction of their genetic diversity and potential for adaptation to other natural or anthropogenic stress factors.
Microevolutionary transformations follow the pattern of r-selection, i.e., occur in favor of smaller, earlier maturing individuals capable of expending a greater proportion of their
energy resources for reproduction. 相似文献
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T. I. Moiseenko 《Russian Journal of Ecology》2011,42(6):485-492
The development of concepts concerning the stability of aquatic ecosystem and their variation under conditions of toxic pollution
and after its reduction is considered. General trends in ecosystem transformation are explained in terms of theoretical ecology
and thermodynamic mechanisms of energy ordering in living systems. Basic symptoms of disorganization in ecosystems under extreme
loads and of their regenerative self-organization are discussed. It is shown that the development of a new modification of
an aquatic ecosystem after a decrease in toxic pollution complies with the pattern of ecosystem succession: from a natural
ecosystem, via the critical stage, to its more stable but structurally different modification. 相似文献
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Trace metal accumulation and fish pathologies in areas affected by mining and metallurgical enterprises in the Kola Region, Russia 总被引:2,自引:0,他引:2
Throughout the Kola region of Russia there has been a substantial increase of metal concentrations in water, which are related to local discharges from metallurgical and mining industry, transboundary transmissions as well as indirect leaching of elements by acid precipitation. This study presents data on the levels of Ni, Cu, Sr, Al, Zn, Co, Mn, Pb, Cd, Hg in the organs and tissues of fish, and evaluates relationships with water chemistry. Special attention is paid to fish pathologies, whose aetiology is related to the accumulation of metals and the associated changes of the elementary ratios within the organism. Ecotoxicological assessment of the copper nickel, strontium and acidification regimes also is considered in this article. In general we observed a large number of lakes that are heavily contaminated by Ni and Cu. Fish in these lakes contain high concentrations of Ni and Cu and display frequent pathologies, mostly associated with the kidneys. In lakes contaminated with Sr, there also are high Sr levels in fish and pathologies associated with skeletal tissues. Exposure to acidified water appears to increase the transport of metals (including Al, Ni and Cu) into fish and hence the toxic effects. 相似文献
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