Home – Home – Jornals – Contemporary Problems of Ecology 2014 number 6

In recent decades, an issue concerning the environmental quality and ecological safety has been frequently raised at the global, regional and local levels. The intensive natural-resource development of Siberia leads to a deterioration of the nаtural environment of the region, which was previously almost unаffected by the anthropogenic influence. There are some peculiar features associated with both the specific nаtural conditions and the types of anthropogenic impact. The paper presents the data on environmental pollution, land degradation, and nаtural disasters. Key actions to reduce the environmental hazard in the Siberian region were planned. An attempt to give an integrated assessment of the ecological safety of Siberia was presented.

The paper concerned biological diversity and population of mammals of the Taimyr Peninsula. The information on the distribution of mammals in different natural zones and subzones of the northern part of Central Siberia was presented. Resource assessment of economically important and rare species requiring protection was given in annotated reports. The last sections were devoted to the ecological assessment of small mammal communities living in different natural landscape zones of the peninsula.

Spatial differentiation of bird populations of the Putorana Plateau was analyzed. There are 137 nesting species in the region. Species diversity, population density and abundance of the majority of the birds have been decreasing. The density of bird populations decreases mainly in the course of transition from the subalpine to the alpine belt; such decrease is less pronounced at the transition from the forest to the subalpine belt. Most of the bird species occur in the wide range of altitudes usually encompassing at least two altitudinal belts. Population density of birds inhabiting the alpine, subalpine, and forest altitudinal landscape belts decreases in easterly direction: from the Putoranа Plateau to the Koryak Upland. Spatial dynamics of the bird population density and abundance of the majority of common species in the Putorana Plateau tends to increase from the highest inner regions of highlands to their periphery. Bird communities of the forest belt of the Putorana Plateau are more diverse and stable compared to those of the alpine and subalpine belts. In addition to high coefficient of similarity of populations, minimal amplitudes of species diversity and bird population density, relatively uniform distribution of more than 50 % of species over the territory of the region, and inessential provincial distinctions in the composition of dominant species were revealed here.

The study concerned the investigation of soil cover of tundra and forest-tundra belts in the western part of the Putorana Plateau. The substantive-genetical classification of soils was developed on the basis of large amounts of morphological and physicochemical data. Subaerial aeolian deposits were widely spread in the mountain tundra belt. The largest areas were occupied by cryometamorphic soils (granuzems) and organic-accumulative soils along with abrazems. Cryoturbated soils (cryozems) prevailed in the lowland forest-tundra area where they had developed on sand-loam glaciolacustrine deposits.

The content of chemical elements in soils and plants collected from the tundra ecosystems of Western Taimyr (Russia) was studied to determine the factors influencing the chemical elements concentration in plants and soils. Naturally high Be, Cu, Mn, Nb, Ni, Pb, Sr, V, Zn contents were found in soils, most likely due to polymetallic ores deposits in the region. The increased accumulation of Fe, Mn, Ni, Pb, Cd by plants was also observed, which could be attributed to low soil pH and abundant soil water content.

A review of the studies carried out by the Institute of Forestry in Norilsk industrial region was presented. The impact of mining and metallurgical industry on forest-tundra vegetation was discussed. Several methodological approaches concerning research organization and monitoring of the environment in the regions under extreme technogenic impact, as well as estimation of damage from industrial objects, were suggested. Zoning of the territory by the level of technogenic impact was done according to degradation of vegetation cover and other biogeocenoses components. The territory was divided into several areas: technogenic wasteland, zones with technogenic biogeocenoses, moderate and mildly disturbed ecosystems.

The paper discusses the development of an automated classification of forest growth conditions based on the analysis of GIS data in order to assess the current state of forest vegetation and to build spatial models of its regeneration dynamics. An area located in the northern part of Siberia, close to the Yenisei River, was used as the experimental site to test and improve a methodology of automated classification and mapping of forest growung conditions based on a spatial analysis of a digital elevation model (SRTM 90m) and ground data. Using the classification of heterogeneous data done in Knowledge Engineer Module three layers of potential forest growth conditions were formed to serve as a base for automated mapping of vegetation dynamics.

The study was based on the field data collected in the Norilsk industrial area (2001–2004) and remote sensing imagery (1998–2004). The vegetation degradation was assessed using multispectral satellite sensor ENVISAT MERIS. The terrestrial ecosystems dynamics was analyzed using SPOT VEGETATION satellite data recorded at different time periods. The regression models were developed for the Ni–, Cu– and S–containing pollutants allocated in the terrestrial ecosystems components. The vegetation degradation and pollution degree were also estimated using marking system. The area of study was also zoned by vegetation degradation degree.

The diversity of vegetation of the study area was represented by 17 associations, 9 alliances, 7 orders, and 6 classes. The geobotanic maps of the region were compiled for the first time using modern technology. The medium-scale mapping of natural vegetation was also carried out. It was shown that the spatial structure of the vegetation in the flat lands was presented mostly by ordered structures - complexes and by fewer disordered structures - combinations. In the western part of the territory, which had experienced a greater impact of humid climate of the Atlantic, there was noted a prominent role of subalpine meadows. The Eastern part of the region had always been under the influence of the cold Siberian anticyclone. So in the subalpine altitudinal zone of the Eastern part the combinations with alder played the central role, and in the forest belt the grassy bogs and tundra-swamp complexes were more important. Anthropogenic changes of the vegetation, that had taken place due to the impact Norilsk factories emissions, were detected. The zones of strong, medium and low anthropogenic impact and the stages of vegetation degradation were specified. The cartographic models of transformed vegetation helped to reveal specifics of the spatial structure of the transformed vegetation depending on the elements of the relief. As the emissions from the enterprises were regular, the impact of pollutants (hydrogen sulfide, in particular) on vegetation was constant. Vegetation was dying without ever getting to the recovery stage. The impact of pollutants proved to be an additional ecological factor that significantly changed the environment and created new artificial ecosystems in which species diversity was greatly reduced among all the systematic groups of higher and lower plants. Especially it concerns slowly regenerating plants: mosses, lichens, some species of shrubs, dwarf shrubs and trees. Thus, natural restoration of vegetation is yet impossible due to high level of pollution. Anthropogenic factor plays the limiting role in the region.

The analysis of topoecological differentiation of vegetation in the Norilsk industrial region, reflecting the response of plant communities on the technogenic impact, was conducted. The basic directions of phytocenotic successions, involving replacement of forest associations by tundra and meadow-marsh complexes, were detected. It was noted that upland areas, depending on their orographic confinement and distance from the source of technogenic emissions, were dominated by mono- and oligodominant herbaceous and shrubby plant communities, which had replaced moss-lichen and shrub associations. The highest level of biodiversity and productivity was shown by meso- and hygromorphic ecosystems on low terraces which were considered to be regional cenotic refugiums.

It was shown that carbon sequestrating role of phytomass decreases almost 30 times along the pollution gradient. The processes of copper and nickel release during decomposition and their consumption during production synthesis are unbalanced. Dead plant material serves as a sorption, sedimentation and mechanical barrier where heavy metals and sulfur concentrate.

The radial growth of Siberian larch under the impact of pollutants emitted by the enterprises of Norilsk was analyzed to reconstruct die-off dynamics of larch stands located along Rybnaya River, along the main direction of pollutant air transport. Dendrochronological cross-dating was used to detect the year of die-off of 268 trees growing at 4 sites located at 22, 45, 68 and 85 km from Norilsk. Death of individual trees at the sites nearest to Norilsk was recorded immediately after the first enterprises had started to operate in early 1940s. Mass mortality of the trees had started in 1960s due to operation of new smelters and consequent increase in pollutant emissions. Complete degradation of the stands (100 % die-off of larch trees) had occurred in 1970s. At the most distant site (85 km), the highest rate of larch had been observed between 1975 and 1980 and in 2004 only 23 % of larch trees were alive. Comparative analysis of tree-ring width of the studied trees testified on decrease of tree radial growth at the period before the complete degradation of stands. Unfavorable climatic conditions became an additional factor that enhanced the rate of tree die-off due to the impact of pollutants. Although the increase of tree radial growth had been found in late 1990s - early 2000s at the site located 85 km from Norilsk, the status of studied trees indicated that the area of completely degraded forest ecosystems might become larger under the present conditions.

The current state of peat deposits in bog ecosystems within the emission plume from Norilsk industrial area was investigated. On the basis of a visual survey and analysis of physical, chemical and geochemical properties of the peat it was determined that the bogs in the four key areas, located further than 80 km from the source of emissions, had been only slightly exposed to anthropogenic influences. The bogs, located at a distance of 45 km from Norilsk had received severe technogenic impact.

It was shown that hilly peatbogs had proved to be informative in estimating technogenic changes of the environment. It was established that active accumulation of heavy metals and sulfur took place in the upper levels of peat deposit (on the depth of 5 cm, more rarely - 15 cm). Passage of technogenic fluxes through peat deposit did not exceed 30-35 cm. The control of negative changes under the effect of sulfur emissions was proved desirable to carry out in bog ecosystems of the Rybnaya River valley. Negative changes happening due to the impact of heavy metals should be controlled on the territories near industrial enterprises of the cities Norilsk and Talnakh.

Soils and rocks of natural and technogenic landscapes in the Norilsk industrial region were studied. The main sources of heavy metals and sulfur in cryogenic soils were identified. The peculiarities of elemental composition in cryogenic soils in comparison with non-cryogenic soils were presented. Spatial and subsoil element concentration were determined. Soil and geochemical zoning of the territory was carried out on the basis of rich quantitative data.

The analysis of ecological and functional state of soils within the zone of technogenic impact of Norilsk industrial plants was made. The criteria used for evaluation were: the content of heavy metals and sulfur as well as microbiological activity of the soil. The basic polluting elements were distinguished. As it was determined, the areas of extreme concentration of heavy metals in soils near the sources of emission were located along the directions of the prevailing winds. Structural and functional abnormalities in the soil microbial complex were marked out in case of strong disturbance of vegetation.

The results of long-term studies of the fauna condition in the zone of impact of emissions from the Norilsk industrial complex were presented. Natural factors influencing the species structure and population characteristics were investigated. The analyses of vegetation state and animal population parameters were conducted. That allowed carrying out zoning of the pollutants’ impact on different ecosystems. The list of indicator species for monitoring of pollution was determined, and contamination level of tissues of terrestrial vertebrates was estimated.

Ecological and entomological observations of some key areas in Norilsk industrial district which were subject to technogenic impact were conducted during 2008-2009 field seasons. The preliminary taxonomic and biodiversity studies of the entomological complex were made from an indicative point of view. The activity of main trophic groups was also estimated. Flexible reaction of phyllophagous groups on technogenic emission was observed. The necessity of monitoring of the impact zone’s marginal areas was noted.

The study of soil invertebrate communities in the forest-tundra area under technogenic pollution showed that the further from the pollution source the higher the density of soil invertebrates. Dependence of meso- and mаcrofauna on the concentration of heavy metals (Ni, Co, Cu, Pb) in forest litter was revealed. Low density and diversity of large saprophages, degradation of litter invertebrate complex and increasing abundance of predators and phytophagous species indicated the depressed state of forest-tundra ecosystems affected by anthropogenic impact.

The content of pollutants in snow samples and their composition were determined. The obtained data on the contents of nickel, copper and other heavy metals and sulfur were used to assess the patterns of snow cover pollution in the Norilsk industrial area. Maps of spatial distribution of heavy metals and sulfur in the region were compiled. The major part of the pollutants entering the atmosphere in the form of dust was deposited on the underlying surface near the sources of industrial emissions (up to 7 km from them). The pollutants entering the atmosphere in the form of aerosols and gases were transported over considerable distances. Greater concentrations of water-soluble forms of sulfur, compared with the background, were marked at a distance of more than 400 km. Calculations showed that only 2 % of sulfur emissions were deposited within 250 km from the sources of emissions, and the remaining portion of sulfur incorporated into the global geochemical cycles.

The results of biological recultivation in different areas affected by industrial emissions around Norilsk were presented. The content of heavy metals in recultivated soils, as well as microbiota’s activity were studied. Plant species resistant to industrial emissions in the Norilsk industrial region were identified.