Дата публикации: 08 октября 2021
Автор(ы): Tatyana MOISEENKO, Alexander SHALABODOV, Sergei GASHEV →
Публикатор: Научная библиотека Порталус
Рубрика: ЭКОЛОГИЯ →
Источник: (c) Science in Russia, №4, 2012, C.13-19 →
Номер публикации: №1633681102
Tatyana MOISEENKO, Alexander SHALABODOV, Sergei GASHEV, (c)
by Tatyana MOISEENKO, RAS Corresponding Member, Head of the Biogeochemistry and Ecology Department of the Institute of Geochemistry and Analytical Chemistry named after V. Vernadsky; Alexander SHALABODOV, Dr. Sc. (Biol.), Director of the Institute of Mathematics, Natural Sciences and Information Technologies of Tyumen State University; Sergei GASHEV, Dr. Sc. (Biol.), Head of the Chair of Zoology and Evolutionary Ecology of Animals of the same university
How to give an objective assessment of water arteries of Western Siberia, a region that is crucial for the economic development of our country? How big are negative consequences of oil-and-gas extraction and other anthropogenic loads on the nature of the territory making up 14 percent of Russia? Answers to this questions can be obtained only according to the results of comprehensive ecological studies.
Water meaning emblem (proposed by S. Gashev).
Map of Tyumen Region lakes.
The project "Formation of Water and Ecosystem Quality in Terms of Anthropogenic Loads and Climatic Changes in Western Siberia", developed by our team, was acknowledged as one of the 40 winners of the open public contest organized by the RF Government with the intent to support surveys carried out by leading national institutes in 2010. The two-year state grant made it possible to set up an analytical state-of-the-art laboratory at the Tyumen State University that proved to be highly useful for getting important data on the ecologically balanced use of the natural wealth in Western Siberia.
The project initiated in 2010 and headed by one of the authors of this article-Tatyana Moiseenko, RAS Corresponding Member, implied an unconventional research schedule and new research methods. Why?
The problem of qualitative depletion of water resources has come to the fore in recent decades, as in many cases an anthropogenic factor is no less significant for the formation of chemical composition of waters than natural geochemical and biological processes. Mining, pollution of rivers with industrial and household waste waters, transformation of gutters due to industrial development of territories-all these things lead to negative effects. Climatic changes do not stand aside either-temperature mode determines mobility of chemical elements in ecosystems. As a result of transborder transfer of toxic substances with air, heavy metals and chlororganic compounds have been detected even in remote high-altitude and arctic lakes.
In other words, water ecosystems are affected simultaneously by local and global factors, and to study their consequences, it is necessary to conduct interdisciplinary research for a complex assessment of water quality.
WHAT IS WATER QUALITY?
What kind of water can be taken as a quality sample, what criteria can be adopted for its assessment? These
questions only seem to be simple, while today we are not able to give simple answers. Perhaps, the most rational thing is to proceed from water consumption: for example, industrial waters have their own assessment criteria as compared with water used in natural or artificial reproduction of fish. But as we are speaking of the natural wealth crucial for all living organisms, including man, the researcher should apply a broader approach.
In Russia, as in many other countries, monitoring of natural water resources consists in measurements of the content of this or that substance (usually toxic) and whether it exceeds the maximum admissible concentration (MAC) or not. This indicator is constant for each monitored substance irrespective of the place of research-in Arctic or arid regions. In other words, behavioral characteristics of the pollutant in specific landscape-geographical conditions are not taken into account. Meanwhile, external factors may boost or diminish its effect, which means that MAC-based assessment approach is not universal.
For this reason hydrochemists offer to assess quality of waters and set up pollution rates on the basis of the so-called average background values of indicators of their chemical composition (i.e. measured in water bodies of the same area, that have never experienced anthropogenic intervention). Results of measurements carried out in such water bodies represent a spread of values, and this spread, typical of natural environment, is then processed by statistical methods-the average value is added to 1-2 square deviations (a square root of a random value dispersion), i.e. values devoid of physical meaning.
In their turn, biologists consider it necessary to assess water quality by revealing disorders in the state of animals, their populations and communities. However, it is not always clear when (i.e. under what kind of indicators of chemical composition of waters) the registered transformations have taken place.
At the same time, if we put aside our subjective requirements to water quality as consumers and consider this problem from ecological point of view, we can make the following conclusion. Quality of water means properties of water formed as a result of chemical, physical and biological processes both in a water body and a drain. It can be assessed positively, if organisms living in and adapted to a specific habitat, develop normally and keep reproducing, in particular, the most sensitive organisms. If the latter condition is met, we can say (with rare exceptions) that such water is safe for human health.
It is obvious that water quality assessment procedures in experimental or natural conditions should be based on the results of fundamental research in the field of life- and geosciences. Here are two "milestones" of our conception: regularities of migration, transformation, sedimentation (precipitation), and behavior of anthropogenic elements, their interaction with natural factors; regularities of anthropogenic variability of ecosystems, their stability and adaptation limits, borderline states.
We are convinced that it is not possible to create a sound water quality assessment system and develop an impact rating system without in-depth studies of water properties forming today and response reactions of living systems to anthropogenic pollution.
TECHNOGENIC THREAT TO WATER ARTERIES OF SIBERIA
Although many regions of Western Siberia do not suffer from water deficit, today we are facing a problem of qualitative depletion of water resources due to local and global anthropogenic loads. Unfortunately, Russian economy is still making use of the natural resources of the country, and over 6 percent of global oil reserves are concentrated in this region. The result is that surface waters contain increased concentrations of phenols, ammonia, copper, zinc, manganese and ferrum compounds, but the principal threat for rivers and lakes of the Ob-Irtysh basin comes from petroleum hydrocarbons, making up 80 percent of all pollutants. Some toxic substances are carried by air to big distances, and we register them in places where natural environment seems to preserve its initial state. It is worth saying that these places and regions are natural depositories of unique species of fish, such as Siberian whitefish, Siberian powan, broad whitefish and muksun.
In recent years a number of Asian countries-China, Mongolia, Kazakhstan, etc.-have increased industrial emissions of carbon dioxide and other acid-forming gases, metals and other hazardous substances, and forecasts are depressing. The problem is that Western Siberia is on the way of air flows carrying the said pollutants to the north-western direction. As a result, quality of water in the southern regions and oil production areas is almost critical. Many elements and chemical compounds brought to ecosystems by man are able to transform, directly or indirectly, living organ-
isms causing toxic, cancerogenic, teratogenic and mutagenic effects.
Scientists handling the problem of technogenic pollution are also attracted by Western Siberia as a unique geographical object incorporating different natural climatic zones (from tundra to steppe) and landscapes (arctic, marshy, taiga and forest), which enables them to carry out in-depth theoretical studies to cognize natural laws, determining anthropogenic variability of physical and chemical properties of waters in the present-day conditions.
By the way, a target-oriented program "Clear Water" is being developed now on the initiative of the RF State Duma and other interested institutions; it will be implemented in the context of results obtained by our researchers.
LARGE-SCALE INTERDISCIPLINARY STUDIES
The proposed research structure consists of three interrelated blocks. First, we study geographical and physico-chemical transformation characteristics of abiotic media, associated with pollution and climatic changes. Secondly, we analyze the response of living organisms to these effects, including long-term biochemical and cytogenetic consequences. Finally, we determine critical impact levels for different pollutants, taking into account varying natural conditions and develop a strategy of water usage and recovery of ecologically impaired territories (water areas).
The completion of such a large-scale task requires solid scientific support provided by the Institute of Mathematics, Natural Sciences and Information Technologies of the Tyumen State University, head of the project. The Tyumen State University, a university that has a number of big grants-"Formation of Innovative Scientific and Educational Complex of the Tyumen University for Efficient Environmental Management in Terms of Intense Development of Natural Resources in Western Siberia", "Research and Development of Priority Trends of Science and Techno-
logy", "Development of Scientific Potential of Universities (2006-2008)", including our project, etc.-is today well equipped. The university has it own laser scanning motorized microscope LSM 5 LIVE DUO SCAN (produced by the well-known German company Karl Zeiss) with a sample preparation system; automatic rotary microtome HM 360S with a section transfer system STS, DNA sequenator, nuclear (proton) magnetic resonance spectrometer Hewlett Packard SPM 2R T21, atomic emission spectrometer with a mass detector Agilent-7500 for an element analysis of samples (ICP + MS), liquid chromatograph Agilent-1100 with a mass-selective detector (to analyze supertoxicants-benzpyrene, dioxins, chlorophenols, etc.), capillary electrophoresis system Agilent-3DCE (to analyze medicines, poisons, toxic substances). Thus, the laboratory of water quality, stability of water ecosystems and ecological toxicology was ready to carry our tests and research activity at short notice.
In 2011, in order to achieve goals set in the project, we organized large-scale expeditions and research works in the Tyumen Region-the only region in Russia covering the territory (together with autonomous territories) from the Arctic Ocean in the north to the state border in the south. To survey such a vast territory, incorporating some natural zones-from tundra to steppe-we organized seven groups of specialists, who carried out works on the basis of a single unified procedure, based on foremost world research practices in hydrochemistry, geoecology, ecology and biology. In particular, we conducted express-surveys of lakes and took samples of 110 water bodies of different size. Geobotanists, ornithologists, zoologists, hydrochemists, hydrobiologists and paleoecologists obtained very interesting results working with model drains (10 sites in tundra, taiga and forest-steppe zones). Paleoecologists took samples of bottom sediments there and carried out geochemical and diatomic analyses*.
Data on the water and near-water ecosystems in conditioned-background regions (not experiencing direct anthropogenic impact) were taken as a "reference point" for assessment of pollution effects, though even remote autonomous landscapes, located far away from industrial centers, fall under the influence of transboundary transfer of toxic substances.
Ecological surveys have their specific characteristics: seasonal sampling restrictions, biological and chemical analyses of samples are rather difficult. Specialists know well: processing of samples takes a year or two on the average, which makes it impossible to complete the project in 2.5 years. However, at the present moment we have data enabling us to make conclusions on the state of water and near-water ecosystems of Western Siberia, and soon we'll be able to offer a rational plan of environmental management.
It has turned out that the natural background for such microelements as Fe, Mn and Al in the region under consideration exceeds the maximum permissible concentration tenfold. At the same time concentrations of the said elements, except for Fe, are quite low in the waters of tundra and taiga zones of Western Siberia. As for the forest-steppe, decreased moisture content and carbonate content of soils provoke accumulation of Sb, Zn, and Pb.
On the basis of obtained data we developed vulnerability assessment methods for the surface waters of the Tyumen Region to acidic precipitation and determined their critical loads. After surveying transformations of ecosystems in historical perspective, it was discovered that on the example of the natural park "Kondinskiye Lakes" (Khanty-Mansi Autonomous Area), acidification of the local water bodies increased and the anthropogenic impacts exceeded all permissible levels before 2000. However, by 2008, there was registered a tendency to recover the environment in Lake Arantur, which agrees with the general European situation: in the original alkalinity of waters is gradually increasing together with their acid-neutralizing properties.
After the detailed studies of mechanisms of electrostatic sorption of metals and formation of metalhumus complexes, we managed to develop a procedure for theoretical calculation of concentrations of these substances in the natural media of the region. The results of data analysis carried out for 140 water bodies enabled to make relevant forecasts for rivers and lakes located in different zones. The discovered regularities can be used to assess toxicity of pollutants and adjust water quality standards.
The ichthyologists, making part of the expedition, made their own research and finally substantiated physiological standards for fish, living in the water bodies of Western Siberia. To assess the state of fish
* See: T. Moiseenko, "What Tarns and Arctic Lakes Tell Us", Science in Russia, No. 6, 2006.--Ed.
Science in Russia, No.4, 2012
populations in the background lakes located in different natural and climatic zones of the Tyumen Region, scientists studied morphological and histological indicators of organs and tissues of the principal representatives of the arctic fresh water (loach, whitefish) and boreal-plain (roach, perch) fauna complexes. In the arctic tundra-Gydan and Yamal peninsulas-hampered maturation and extension of the sexual cycle of the selected species are explained by poor feeding and short fatting period. As for the taiga zone, scientists registered a number of deviations of the examined organs and poor development of the reproductive system, but in general the ecological situation is more favorable there.
The cytogenetic analysis of embryos of different species of whitefish, living in the polluted water systems of the Tyumen region, showed: frequency of chromosome breakages is an efficient biomarker indicating presence of pollutants. Specialists established: quality of waters in the Ob-Irtysh basin, in particular, its spawning areas, deteriorated so much that mutagenicity of this medium increased, which is proved by dynamics of an increased frequency of chromosome breakages in the cells of developing fish embryos.
According to the results of our laboratory experiments, pollution of water with crude oil provokes a nonspecific reaction in the organisms of small mammals and becomes a stress factor for animals, which agrees with the results of field surveys in oil-contaminated territories. The rodents forced to take an oil "diet", showed accelerated metabolism affecting their heart, kidneys, and liver. Poisoning effect was also proved by a simultaneous increase of the spleen index and lowering of the Hb level in those animals that consumed the said toxicant. In addition, scientists registered breakages of the processes of haemopoiesis, increased level of lymph cells in the blood and other changes. They also established that adaptation to such unfavorable conditions is a specific process in the species, sex and age of different groups within one
species, along with the active participation of the hypothalamic-hypophysial-adrenal system.
To assess the environmental conditions, we also used bioindication methods, based on the adequate response of animal communities and certain populations to changes in the habitat. It is worth saying that the negative response was registered in the ecosystem structure, as well as in morphophysiological and histological level of forms. Ornithologists carried out studies within a conventional corridor (transect) of about 3,000 km in the direction from the north to the south. Observations made on 12 sample sites in different natural zones of Western Siberia showed: the shift of northern boundaries of the area of distribution of birds in the region under consideration was undoubtedly predetermined by a widely-discussed climate warming registered in the course of 15 years of the 60-year astronomical cycle. However, the temperatures rose only in summer, due to which migratory birds, including water and marsh species, settled in new areas, while cold winters make all birds fly to the south. In other words, it would be more correct to speak about the increased continental nature of the climate.
Results of interdisciplinary surveys, partially set forth in this article, served as a basis for working out of practical recommendations for efficient environmental management. Our group is working on this issue at the moment. National scientists are trying to find ways for preserving purity of rivers and lakes of Western Siberia, its vast and picturesque boggy lands-one of the most urgent present-day tasks, since it determines not only biodiversity on our planet, but also life and health of people.
Опубликовано на Порталусе 08 октября 2021 года
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