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31.
Many-year (1981–2009) variations of hydrochemical and hydrobiological characteristics of the state of the aquatic environment in the Lower Volga are presented. The development and transformation of the structural organization of aquatic organism communities are considered against the background of a tendency toward the accumulation of key pollutants and the regional features of those processes are considered. The study has shown that the aquatic ecosystem of the Lower Volga functions with its ecological state disturbed because of the strengthening of ecological regress. 相似文献
32.
Long-term data from Rosgidromet and research results were used in comparing the chemistry condition of the southern reservoirs (Tsimlyansk, Proletarsk and Veselyi) to reveal that the ecologo-toxicological indices and characteristics of such intra-waterbody processes as pollution, eutrophication and toxification differ substantially. In the first place, the differences apply for the hydrochemical regime and mineralization as well as for individual biological indices. Common to the reservoirs are a stable (chronic) character of chemical contamination (in spite of its relatively low level), and a long-lasting presence of stable organochlorine pesticides in the composition of contamination, and a decline in biodiversity. The Tsimlyansk and Veselyi reservoirs show a similar seasonal dynamics of the phytoplankton, and a predominance of blue-green algae in the phytoplankton community. An unfavorable factor for the ecosystem of the Tsimlyansk reservoir is represented by annually recurring water bloom, with a large-scale occurrence of toxic species of algae, and by an increase in toxicity of natural water (toxification). 相似文献
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34.
The thermal regime of the surface water layer in a water body is studied, and its effect on the mass and gas exchange in the water body-atmosphere system is examined by using a mesocosm as a microecosystem model. 相似文献
35.
Water Resources - The relative importance of indicators of biotic and abiotic components of water ecosystems of the Tsimlyansky and the Manychsky (Proletarian and Veselovsky) reservoirs in the... 相似文献
36.
A three-level scheme is proposed for the identification of sources of fresh and old petroleum pollution of water bodies and streams, including an optimal complex of simple, available, and highly effective physicochemical techniques, criteria, and sample processing methods ensuring the reliability of conclusions derived from them. The efficiency of application of the proposed methods is illustrated in several water bodies and streams (the Bol’shaya Krepkaya, Tuzlov, Chitinka, and other rivers), which have experienced oil pollution. 相似文献
37.
Analysis of long-term regime hydrochemical data collected by the State Service of Environmental Monitoring (SSEM) was used
to assess the anthropogenic load on the near-delta area of the Enisei mouth area near Igarka and Dudinka towns. Main trends
in the accumulation of biogenic compounds and pollutants, such as oil products, phenols, and copper and iron compounds are
identified. It is shown that the current anthropogenic load and the degree of aquatic environment pollution bring about a
trend toward the transition of the Enisei near-delta ecosystem from equilibrium into a crisis state. 相似文献
38.
The discharge of organic and biogenic substances by Russian rivers into the Arctic and Pacific seas, their anthropogenic component,
and the trends in variations in the runoff of some components in individual periods of 1981–2000 are estimated. 相似文献
39.
A. M. Nikanorov D. N. Gar’kusha E. A. Zubkov O. B. Bartsev L. I. Minina 《Water Resources》2018,45(2):205-212
Seasonal dynamics of the mineralization, ionic composition, and the concentrations of specific pollutants in subsoil water are studied in populated localities in the southern Rostov oblast. Four major water types are identified: hydrocarbonate–sulfate (sulfate–hydrocarbonate), sulfate, chloride–sulfate (sulfate–chloride), and mixed type of subsoil water. The quality of subsoil water was found to fail to meet the sanitarytoxicological standards in terms of many characteristics. The values of MAC are exceeded for calcium, magnesium, sodium, chloride and sulfate ions, oil products, cadmium, total iron, silicon, and nitrate and ammonium nitrogen. Relationships were found to exist between the concentrations in water of cadmium, potassium, and phosphorus ions; oil products; pH values; water mineralization and total hardness; and seasonal variations of subsoil water levels. The identified relationships were substantiated. 相似文献
40.
A series of field experiments were carried out in natural model ecosystems (mesocosms) with the aim to study the effect of
pollutants on processes proceeding within water body. The generalized thermodynamic state parameters used in the study were
the rate of photosynthetic production and destruction of organic matter. The ratio of destruction to primary production and
the rate of changes in this ratio were used to construct phase portraits of ecosystems. Analysis showed that the dynamics
of ecosystem states described by those characteristics corresponds to the general regularities in the evolution of the state
of dissipative structures, hence the rate of changes in the destruction-to-production ratio can be taken as a thermodynamic
criterion of evolution of aquatic ecosystems. The proposed approach allows this criterion to be used to develop methods for
standardization of ecological loads. 相似文献