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Cartographic assessment of pollution of forest ecosystems on the Baikal natural territory by technogenic emissions
Geography and Natural Resources 29 (2008) 317–320
Cartographic assessment of pollution of forest ecosystems on the Baikal natural territory by technogenic emissions T. A. Mikhailova *, A. S. Pleshanov and L. V. Afanasieva Institute of Plant Physiology and Biochemistry SB RAS, Irkutsk Received 14 February 2008
Abstract The implementation of these authors’ original approaches in generating maps of forest pollution and vital status of forest stands in a large region is outlined. The maps so far developed can be considered basic, reflecting the phenomena to be subsequently monitored in order to make justified forecasts of the state of forest vegetation on territories exposed to pollution, including under changes of the level and character of emission load. Keywords: atmospheric industrial pollution, forest ecosystems, mapping.
Introduction The Baikal natural territory (BNT) lies at the heart of Asia on the territory of Russia [1]. In accordance with the Law “About the protection of Lake Baikal” [2], it includes Lake Baikal and the adjacent catchment area (within Russia) as well as the territory up to 200 km in width to the westnorth-west of the lake. Its total area is 38.6 mil. ha. The uniqueness of the BNT derives from the great variety of natural complexes, the characteristic properties of mountain-depression topography, and by a high degree of contrast of the biogeographical and bioclimatic situation. The forests within the Lake Baikal watershed basin are represented by ecosystems of high, middle and low mountains, tablelands, depressions, and plains [3]. The structure of forest stands is dominated by conifers, with pine constituting 31%, larch 33%, Siberian stone pine 12%, spruce and fir 45, smallleaved species (birch, aspen, and shrubs) about 20% [1]. It is common knowledge that the forests around Baikal are of vital importance in stabilizing the natural environment. Suffice it to say that about 80% of the liquid runoff flowing into the lake originate in the mountain-taiga belt of the Baikal watershed basin as well as in subtaiga forests, and in subalpine open forests [3]. Among the numerous adverse factors having influence on the forests, atmospheric pollution, along with forest fires, is *
Corresponding author.
coming into particular prominence. Its effects are especially dangerous for conifers which are distinguished by enhanced sensitivity to pollutants. It was shown that Daurian larch, Siberian larch, common juniper, Siberian spruce, common pine, Siberian stone pine, and Siberian fir, when compared with deciduous species, have an order-of-magnitude lower resistance to acidogenous gases: hydrogen fluoride, and sulfur dioxide [4]. The importance of industrial emissions as a detrimental ecological factor affecting the life status of forests stands on the BNT derives from the Baikal region’s ever increasing powerful industrialization. This would imply an aggravation of the problems relating to conservation of the structural integrity and resistance of forests. The BNT is home to more than ten major industrial centers: the Irkutsk, Angarsk, Usolye, Shelekhov, Ulan-Ude, Yuzhnobaikalsk, Gusinoozersk, Nizhneselenginsk and other centers whose emissions are characterized by increased toxicity as they include sulfur, carbon and nitrogen oxides as well as hydrogen fluoride, aerosols of heavy metals, and organic compounds. The yearly volume of air emissions from all industries amounts to 400-450 thou t of pollutants [5]. A large body of evidence has been accumulated to date, which provides a means of assessing the forest pollution level and the life status of forest stands on the BNT as well as construct, based on the findings, adequate spatial models, namely, thematic ecological maps. To accomplish this, an analysis was made of the data we obtained during 1995-2007.
Copyright © 2008 IG SB, Siberian Branch of RAS. Published by Elsevier B.V. All rights reserved doi:10.1016/j.gnr.2008.10.015
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T. A. Mikhailova et al. / Geography and Natural Resources 29 (2008) 317–320
Objects and methods of investigation This investigation is concerned primarily with forest stands of common pine (Pinus sylvestris L.), i.e. one of the forest-forming species on the BNT. Pine is distinguished by high sensitivity to atmospheric pollution; based on this, we used it as the indicator. Field survey of the forests was carried out using the techniques approved by the RF state forestry authorities [6, 7] as well as with due regard for the international ICP Forests technique [8]. For these purposes, more than 200 trial areas were established, with their network encompassing the entire BNT. The establishment of the trial areas took into consideration he characteristics of terrain and hydronetwork, the location of pollution sources, the prevailing direction of atmospheric transport of pollutants, and the specific character of the local circulation of air masses. In each trial area, the main forest inventory characteristics were recorded, the geobotanical description was prepared, the level of tree crown defoliation level and the natural longevity of the needles were determined, and the length and mass of the needles and sprouts as well as some other parameters were measured. (N. S. Berezhnaya, O. V. Kalugina and N. V. Yakovchits participated in expeditionbased work, and in the office data processing). In addition, pine needles samples were collected to be used in the analysis for the level of chemical elements: sulfur, fluorine, lead, mercury, cadmium, copper, aluminum, iron, zinc, manganese, calcium, magnesium, potassium, sodium, silicon, phosphorus, and nitrogen (total, protein and nonprotein nitrogen). The forest pollution level and the life status of forest stands were assessed in accordance with our previously developed methodological approach [9, 10]. Essentially, the approach involves the creation and introduction of interdisciplinary integration algorithms for analyzing multiple heterogeneous primary information and generalizing the parameters, and the use of geoinformation systems in the new ecological constructs. The approach implies integrating the methods of field and chemical analytical investigations, and mathematical formalization (including the use of correlation and cluster analysis); the final stage involves mapping with the use of GIS technologies. To map the level of disturbance of ecosystems across extensive territories polluted by industrial emissions requires: a definite, sufficient body of primary information (input data), its mathematical assessment, the formalized construction of classification scales of relevant processes (changes of the pollution level and of classes of status of forest stands), and the searching for correlations between phenomena analyzed (in this case – between the content of toxicants and the parameters of woody plants). Mapping has a systemic character and involves sequentially compiling (on a common landscape-geobotanical basis) a series of thematic maps. For the purposes of this paper, it is the map of fields of vegetation pollution by industrial air emissions, and the map of status of forest stands on the BNT.
The map of pollution fields displays territories polluted largely by emissions from separate industrial centers as well as through intra- and interregional transport of technogenic emissions. These territories are identified using the results of cluster analysis of data on the content of toxicants in the needles of common pine. Usually, each of the cluster identified corresponds to a definite pollution field. Trial areas with the minimum possible values of pollutant elements constitute a background cluster (unpolluted territories). The map of life (physiological) status of forest stands exhibits the degree of their suppression across the polluted territory. On the basis of a set of visual, morphostructural and physiological-biochemical parameters of trees and using cluster analysis, four main classes of life status of the surveyed forest stands were identified: background, weak, moderate and strong suppression [11, 12]. Accordingly, mapping was used to identify territories occupied by forest stands of a different life status. The maps were constructed on the basis of the attributive data base using the ArcView software package in the Universal Transverse Mercator (UTM) system. Results and discussion The results obtained in the study provided a basis for developing medium-scale maps [portraying forest pollution (Fig. 1) and the life status of forest stands (Fig. 2) for the entire BNT. According to our assessment, within the BNT the area of forests polluted to some or other degree makes up about 30% of the forest-clad territory (20% of the total area). As regards the southwestern part of the BNT (in the Prebaikalia), a distinguishing characteristic of aerotechnogenic pollution implies overlapping of emission flows from different industrial centers and formation of a significant ecologically unfavorable territory with a high pollution level. Another characteristic is the wide occurrence of transregional pollution caused by the transport of emissions not only within the territory involved but also from the other regions of Siberia. In the eastern and southeastern parts of the BNT (within the Republic of Buryatia), technogenic pollution of forests has a different, clearly pronounced local, character and is concentrated in the surroundings of large industrial centers: Ulan-Ude, Yuzhnobaikalsk, Nizhneselenginsk, and Gusinoozersk. Transregional pollution affects relatively small areas on the northern macroslope of the Khamar-Daban range and within the delta of the Selenga river; it is not found in the other area of this part of the BNT, however. This is largely due to the orographic features of the Transbaikalia as well as to the fact that industrial emissions are smaller in the volume when compared with the Prebaikalia. As far as the forests in the northern part of the BNT are concerned, they are experiencing insignificant technogenic impacts. Most of this territory remains virtually unaffected by emissions, and only nearby some residential centers are the air emissions found to have only a slight effect.
T. A. Mikhailova et al. / Geography and Natural Resources 29 (2008) 317–320
Fig. 1. Map of pollution of pine forests of the Baikal natural territory. Pollution fields: 1 – Shelekhov, 2 – Irkutsk, 3 – Irkutsk-Shelekhov, 4 – Angarsk-Usolye-Cheremkhovo (severe pollution), 5 – AngaraUsolye-Cheremkhovo (moderate pollution), 6 – Angara-UsolyeCheremkhovo (mild pollution), 7 – Southern Baikal, 8 – Nizhneselenginsk, 9 – Ulan-Ude, 10 – Gusinoozersk, 11 – Transregional. 12 – area of local pollution; 13 – unpolluted territories.
In an earlier study we calculated the areas of the pollution fields identified [11, 13, 14]. Thus, more than 45 thou ha of the territory are exposed to strong effects of the Shelekhov industrial center (the Shelekhov pollution field), and the Irkutsk industrial center’s impact encompasses about 63 thou ha (the Irkutsk pollution field). Their emissions overlap at some distance from these cities; therefore, cluster analysis rather clearly reveals a so-called Irkutsk-Shelekhov medium-level pollution field with an area of about 200 thou ha. A still greater overlap is observed in the case of the emissions from the other three industrial centers: Angarsk, Usolye-Sibirskoye, and Cheremkhovo. According to the results of cluster analysis, the territory polluted by these cities is identified as a single large Angarsk-Usolye-Cheremkhovo pollution field with an area of about 3 mil. ha. On the other hand, the following territories can be identified within this field according to the pollution level: severely polluted – 650 thou ha, and moderately and weakly polluted – about 1 mil. 200 thou ha each. The emissions from the cities of Baikalsk and Slyudyanka produce the Southern Baikal medium-level pollution field (more than 60 thou ha). A separate field (also having a moderate pollution level) is produced by the emissions from Selenginsk and Kamensk, and it has come to be known as the Nizhneselenginsk field (about 200 thou ha). The emissions from the Selenginsk Pulp and Board mill.
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Fig. 2. Map of the condition of pine stands of the Baikal natural territory. Depression: 1 – strong, 2 – moderate, 3 – weak, 4 – background forest stands.
The air emissions from the Ulan-Ude and Gusinoozersk industrial centers, respectively, have influence on about 240 and about 190 thou ha of the territory, and the Ulan-Ude, Nizhneselenginsk and Gusinoozersk pollution fields are characterized mainly by a moderate pollution level; a high level is recorded within the production areas of large enterprises. A further about 40 thou ha (in the aggregate) are occupied by local areas of weak pollution from the emission points located within separate residential centers (town of Kyakhta, settlement of Tarbagatai, town of Petrovsk-Zabaikalsk, settlement of Nizhneangarsk, town of Severobaikalsk, and others). The area of the transregional pollution field in the Prebaikalia is about 8 mil. ha; within the BNT itself, however, it is nearly twice as small. As pointed out above, this field is due to the intra- and interregional transport of emissions. In the remaining forest-clad area of the BNT (about 70%), no pollution of forest stands has been recorded. The pollution fields identified here differ by the quantitative relationship of pollutants and biophilic elements, and by total toxic pressure. Thus, in the Angarsk-Usolye-Cheremkhovo pollution field plant tissue reveal high contents of sulfur and heavy metals, including mercury, lead, cadmium, copper, and iron. The Shelekhov field show very high concentrations of fluorides, mercury, iron, and silicon. The Irkutsk pollution field is characterized by the highest content
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of lead in plant tissues. Some characteristic properties of elemental composition of the pine needles are also identified in the other pollution fields. The map of the status of pine-tree stands displays the territories with a different degree of suppression (see Fig. 2). Thus, forest stands with a high, moderate and weak suppression level were detected across an area measuring 640, more than 2 mil. and more than 5 mil. ha, respectively. Furthermore, strong suppression is recorded nearby large industrial centers and at a distance of up to 30 km from them, while moderate and weak suppression is observed from 30 to 100 km. Background (relatively undisturbed) forest stands usually are at a significant distance from the industrial centers (by 150-200 km). The highest percentage of background forest stands corresponds to the northern, southern and eastern parts of the BNT. In the southwestern (the most polluted) part of the BNT, background forest stands are detected locally – within, for example, the Goloustnaya river basin as well as at the foothills of the Eastern Sayan mountains. According to field survey and analysis of morphostructural and physiological-biochemical parameters of forest stands, the life status of background stands is influenced considerably by natural factors, including the severe climatic conditions, permafrost and seasonal permafrost, frequent forest fires, epiphytotia of micromycetes, and foci of injurious insects. It should be noted that the negative influence from noxious insects and pathogenic fungi is enhanced in forests deteriorated by industrial emissions. The overall tendency is thus: in forest stands with a strong and moderate degree of suppression, insects and micromycetes are able to enhance the deterioration of trees and accelerate the process of their destruction; usually, however, they are not the dominant injuring factor, with some exceptions, though. Specifically, in the fir forests on the northern macroslope of the Khamar-Daban macroslope, epiphytotia (pandemic fungal diseases), because of the specific character of the natural conditions, often play a determining role in the deterioration of forest stands polluted by the emissions from the Baikalsk Pulp and Paper Mill [15]. Conclusion On the basis of the approaches developed previously, we carried out targeted investigations on a regional scale which allowed us to assess with an optimal degree of detail the impact of industrial air emissions on forest ecosystems. For the first time, a comprehensive assessment of technogenic pollution of the forests throughout the Baikal natural territory, a large region in the boreal zone of Asian Russia. The findings obtained in this study indicate that the territory used in out survey has significant environment-protective and waterregulation potential, which is largely facilitated by the high level of its forestation. On the other hand, there is reason to think that the territory tends to be deteriorated considerably by technogenic emissions. Forest stands nearby industrial centers as well as those occupying extensive areas at some distance from them are experiencing adverse effects
of pollutants. In general the findings from the investigations reported in this paper lend support to the need for a continued monitoring in the interests of making well-grounded forecasts of the state of forest vegetation across polluted territories, including in the case of a change of the level and character of the emission loads. This work was done with financial support from the Russian Foundation for Basic Research (03-04-95565, 05-0497219, 05-05-97259) using equipment of the Baikal Analytical Center at the Shared Data Services Center. References 1. Present and Future of the Baikal Region. Novosibirsk: Studio Design INFOLIO, 1996, 112 p. 2. The law “About the protection of Lake Baikal”. Rossiskaya gazeta, 1999, 12 May, p. 4. 3. The “Baikal” Atlas. Moscow: Roskartografiya, 1993, 160 p. 4. Rozhkov A. S. and Mikhailova T. A. The Effect of FluorineContaining Emissions on Conifers. Berlin Heidelberg: Springer-Verlag, 1993, 142 p. 5. State Report “On the State and Protection of the environment in the Irkutsk Region in 2003”. Irkutsk: Oblmashinform, 2004, 297 p. 6. Instructions on Expedition-based Forest-Pathological Survey of the USSR’s Forests. Moscow: Gosleskhoz SSSR, 1983, 234 p. 7. The Technique for Arranging and Conducting Monitoring Operations on the USSR’s Forests. Pushkino: VNIILM, 1987, 45 p. 8. Manual on Methodologies and Criteria for Harmonized Sampling, Assessment, Monitoring and Analysis of the Effects of Air Pollution on Forests. Hamburg; Prague: United Nations Environment Programmee and Economic Commission for Europe, 1994, 477 p. 9. Pleshanov A. S. and Mikhailova T. A. The formalized method of mapping vegetation pollution by industrial air emissions. The Ecological Problems of Urbanized Territories. Irkutsk: Institute of Geography SB RAS Publisher, 1998, pp. 100-105. 10. Pleshanov A. S., Mikhailova T. A., Voronin V. I. et al. Cartographic assessment of the state of vegetation polluted by industrial air emissions from industrial centers of the Angara region. The Problems of Terrestrial Civilization. Irkutsk technical University Publisher, issue 1, pt. 1, pp. 109-113. 11. Mikhailov T. A. Influence of industrial emissions on the forests of the Baikal natural territory. Geografiya i prirod. resursy, 2003, No. 1, pp. 51-59. 12. Mikhailova T. A. The physiological condition of pine trees in the Prebaikalia (East Siberia). Forest Pathology, 2000, v. 30 (6), pp. 345-359. 13. Afanasieva L. V. Influence of Atmospheric Industrial Pollution on Pine Forests Within the Selenga River Basin: Author’s Abstract of Cand.Sc. (Biol.) Dissertation. Ulan-Ude, 2005, 19 p. 14. Mikhailova T. A., Pleshanov A. S., Berezhnaya N. S. et al. Influence of atmospheric industrial pollution on the forests of the Baikal Natural Territory. Vestn. Buryat. un-ta. Ser. 2. Biology, 2005, issue 7, pp. 193-196. 15. Morozova T. I., Oskolkova T. A. and Pleshanov A. S. The condition of fir forests of Khamar-Daban in the influence area of atmospheric emissions from the Baikalsk paper and Pulp Mill. Sib. ekol. l.. zhurn., 2005, No. 4, pp. 701-706.
Cartographic assessment of pollution of forest ecosystems on the Baikal natural territory by technogenic emissions T. A. Mikhailova *, A. S. Pleshanov and L. V. Afanasieva Institute of Plant Physiology and Biochemistry SB RAS, Irkutsk Received 14 February 2008
Abstract The implementation of these authors’ original approaches in generating maps of forest pollution and vital status of forest stands in a large region is outlined. The maps so far developed can be considered basic, reflecting the phenomena to be subsequently monitored in order to make justified forecasts of the state of forest vegetation on territories exposed to pollution, including under changes of the level and character of emission load. Keywords: atmospheric industrial pollution, forest ecosystems, mapping.
Introduction The Baikal natural territory (BNT) lies at the heart of Asia on the territory of Russia [1]. In accordance with the Law “About the protection of Lake Baikal” [2], it includes Lake Baikal and the adjacent catchment area (within Russia) as well as the territory up to 200 km in width to the westnorth-west of the lake. Its total area is 38.6 mil. ha. The uniqueness of the BNT derives from the great variety of natural complexes, the characteristic properties of mountain-depression topography, and by a high degree of contrast of the biogeographical and bioclimatic situation. The forests within the Lake Baikal watershed basin are represented by ecosystems of high, middle and low mountains, tablelands, depressions, and plains [3]. The structure of forest stands is dominated by conifers, with pine constituting 31%, larch 33%, Siberian stone pine 12%, spruce and fir 45, smallleaved species (birch, aspen, and shrubs) about 20% [1]. It is common knowledge that the forests around Baikal are of vital importance in stabilizing the natural environment. Suffice it to say that about 80% of the liquid runoff flowing into the lake originate in the mountain-taiga belt of the Baikal watershed basin as well as in subtaiga forests, and in subalpine open forests [3]. Among the numerous adverse factors having influence on the forests, atmospheric pollution, along with forest fires, is *
Corresponding author.
coming into particular prominence. Its effects are especially dangerous for conifers which are distinguished by enhanced sensitivity to pollutants. It was shown that Daurian larch, Siberian larch, common juniper, Siberian spruce, common pine, Siberian stone pine, and Siberian fir, when compared with deciduous species, have an order-of-magnitude lower resistance to acidogenous gases: hydrogen fluoride, and sulfur dioxide [4]. The importance of industrial emissions as a detrimental ecological factor affecting the life status of forests stands on the BNT derives from the Baikal region’s ever increasing powerful industrialization. This would imply an aggravation of the problems relating to conservation of the structural integrity and resistance of forests. The BNT is home to more than ten major industrial centers: the Irkutsk, Angarsk, Usolye, Shelekhov, Ulan-Ude, Yuzhnobaikalsk, Gusinoozersk, Nizhneselenginsk and other centers whose emissions are characterized by increased toxicity as they include sulfur, carbon and nitrogen oxides as well as hydrogen fluoride, aerosols of heavy metals, and organic compounds. The yearly volume of air emissions from all industries amounts to 400-450 thou t of pollutants [5]. A large body of evidence has been accumulated to date, which provides a means of assessing the forest pollution level and the life status of forest stands on the BNT as well as construct, based on the findings, adequate spatial models, namely, thematic ecological maps. To accomplish this, an analysis was made of the data we obtained during 1995-2007.
Copyright © 2008 IG SB, Siberian Branch of RAS. Published by Elsevier B.V. All rights reserved doi:10.1016/j.gnr.2008.10.015
13
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T. A. Mikhailova et al. / Geography and Natural Resources 29 (2008) 317–320
Objects and methods of investigation This investigation is concerned primarily with forest stands of common pine (Pinus sylvestris L.), i.e. one of the forest-forming species on the BNT. Pine is distinguished by high sensitivity to atmospheric pollution; based on this, we used it as the indicator. Field survey of the forests was carried out using the techniques approved by the RF state forestry authorities [6, 7] as well as with due regard for the international ICP Forests technique [8]. For these purposes, more than 200 trial areas were established, with their network encompassing the entire BNT. The establishment of the trial areas took into consideration he characteristics of terrain and hydronetwork, the location of pollution sources, the prevailing direction of atmospheric transport of pollutants, and the specific character of the local circulation of air masses. In each trial area, the main forest inventory characteristics were recorded, the geobotanical description was prepared, the level of tree crown defoliation level and the natural longevity of the needles were determined, and the length and mass of the needles and sprouts as well as some other parameters were measured. (N. S. Berezhnaya, O. V. Kalugina and N. V. Yakovchits participated in expeditionbased work, and in the office data processing). In addition, pine needles samples were collected to be used in the analysis for the level of chemical elements: sulfur, fluorine, lead, mercury, cadmium, copper, aluminum, iron, zinc, manganese, calcium, magnesium, potassium, sodium, silicon, phosphorus, and nitrogen (total, protein and nonprotein nitrogen). The forest pollution level and the life status of forest stands were assessed in accordance with our previously developed methodological approach [9, 10]. Essentially, the approach involves the creation and introduction of interdisciplinary integration algorithms for analyzing multiple heterogeneous primary information and generalizing the parameters, and the use of geoinformation systems in the new ecological constructs. The approach implies integrating the methods of field and chemical analytical investigations, and mathematical formalization (including the use of correlation and cluster analysis); the final stage involves mapping with the use of GIS technologies. To map the level of disturbance of ecosystems across extensive territories polluted by industrial emissions requires: a definite, sufficient body of primary information (input data), its mathematical assessment, the formalized construction of classification scales of relevant processes (changes of the pollution level and of classes of status of forest stands), and the searching for correlations between phenomena analyzed (in this case – between the content of toxicants and the parameters of woody plants). Mapping has a systemic character and involves sequentially compiling (on a common landscape-geobotanical basis) a series of thematic maps. For the purposes of this paper, it is the map of fields of vegetation pollution by industrial air emissions, and the map of status of forest stands on the BNT.
The map of pollution fields displays territories polluted largely by emissions from separate industrial centers as well as through intra- and interregional transport of technogenic emissions. These territories are identified using the results of cluster analysis of data on the content of toxicants in the needles of common pine. Usually, each of the cluster identified corresponds to a definite pollution field. Trial areas with the minimum possible values of pollutant elements constitute a background cluster (unpolluted territories). The map of life (physiological) status of forest stands exhibits the degree of their suppression across the polluted territory. On the basis of a set of visual, morphostructural and physiological-biochemical parameters of trees and using cluster analysis, four main classes of life status of the surveyed forest stands were identified: background, weak, moderate and strong suppression [11, 12]. Accordingly, mapping was used to identify territories occupied by forest stands of a different life status. The maps were constructed on the basis of the attributive data base using the ArcView software package in the Universal Transverse Mercator (UTM) system. Results and discussion The results obtained in the study provided a basis for developing medium-scale maps [portraying forest pollution (Fig. 1) and the life status of forest stands (Fig. 2) for the entire BNT. According to our assessment, within the BNT the area of forests polluted to some or other degree makes up about 30% of the forest-clad territory (20% of the total area). As regards the southwestern part of the BNT (in the Prebaikalia), a distinguishing characteristic of aerotechnogenic pollution implies overlapping of emission flows from different industrial centers and formation of a significant ecologically unfavorable territory with a high pollution level. Another characteristic is the wide occurrence of transregional pollution caused by the transport of emissions not only within the territory involved but also from the other regions of Siberia. In the eastern and southeastern parts of the BNT (within the Republic of Buryatia), technogenic pollution of forests has a different, clearly pronounced local, character and is concentrated in the surroundings of large industrial centers: Ulan-Ude, Yuzhnobaikalsk, Nizhneselenginsk, and Gusinoozersk. Transregional pollution affects relatively small areas on the northern macroslope of the Khamar-Daban range and within the delta of the Selenga river; it is not found in the other area of this part of the BNT, however. This is largely due to the orographic features of the Transbaikalia as well as to the fact that industrial emissions are smaller in the volume when compared with the Prebaikalia. As far as the forests in the northern part of the BNT are concerned, they are experiencing insignificant technogenic impacts. Most of this territory remains virtually unaffected by emissions, and only nearby some residential centers are the air emissions found to have only a slight effect.
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Fig. 1. Map of pollution of pine forests of the Baikal natural territory. Pollution fields: 1 – Shelekhov, 2 – Irkutsk, 3 – Irkutsk-Shelekhov, 4 – Angarsk-Usolye-Cheremkhovo (severe pollution), 5 – AngaraUsolye-Cheremkhovo (moderate pollution), 6 – Angara-UsolyeCheremkhovo (mild pollution), 7 – Southern Baikal, 8 – Nizhneselenginsk, 9 – Ulan-Ude, 10 – Gusinoozersk, 11 – Transregional. 12 – area of local pollution; 13 – unpolluted territories.
In an earlier study we calculated the areas of the pollution fields identified [11, 13, 14]. Thus, more than 45 thou ha of the territory are exposed to strong effects of the Shelekhov industrial center (the Shelekhov pollution field), and the Irkutsk industrial center’s impact encompasses about 63 thou ha (the Irkutsk pollution field). Their emissions overlap at some distance from these cities; therefore, cluster analysis rather clearly reveals a so-called Irkutsk-Shelekhov medium-level pollution field with an area of about 200 thou ha. A still greater overlap is observed in the case of the emissions from the other three industrial centers: Angarsk, Usolye-Sibirskoye, and Cheremkhovo. According to the results of cluster analysis, the territory polluted by these cities is identified as a single large Angarsk-Usolye-Cheremkhovo pollution field with an area of about 3 mil. ha. On the other hand, the following territories can be identified within this field according to the pollution level: severely polluted – 650 thou ha, and moderately and weakly polluted – about 1 mil. 200 thou ha each. The emissions from the cities of Baikalsk and Slyudyanka produce the Southern Baikal medium-level pollution field (more than 60 thou ha). A separate field (also having a moderate pollution level) is produced by the emissions from Selenginsk and Kamensk, and it has come to be known as the Nizhneselenginsk field (about 200 thou ha). The emissions from the Selenginsk Pulp and Board mill.
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Fig. 2. Map of the condition of pine stands of the Baikal natural territory. Depression: 1 – strong, 2 – moderate, 3 – weak, 4 – background forest stands.
The air emissions from the Ulan-Ude and Gusinoozersk industrial centers, respectively, have influence on about 240 and about 190 thou ha of the territory, and the Ulan-Ude, Nizhneselenginsk and Gusinoozersk pollution fields are characterized mainly by a moderate pollution level; a high level is recorded within the production areas of large enterprises. A further about 40 thou ha (in the aggregate) are occupied by local areas of weak pollution from the emission points located within separate residential centers (town of Kyakhta, settlement of Tarbagatai, town of Petrovsk-Zabaikalsk, settlement of Nizhneangarsk, town of Severobaikalsk, and others). The area of the transregional pollution field in the Prebaikalia is about 8 mil. ha; within the BNT itself, however, it is nearly twice as small. As pointed out above, this field is due to the intra- and interregional transport of emissions. In the remaining forest-clad area of the BNT (about 70%), no pollution of forest stands has been recorded. The pollution fields identified here differ by the quantitative relationship of pollutants and biophilic elements, and by total toxic pressure. Thus, in the Angarsk-Usolye-Cheremkhovo pollution field plant tissue reveal high contents of sulfur and heavy metals, including mercury, lead, cadmium, copper, and iron. The Shelekhov field show very high concentrations of fluorides, mercury, iron, and silicon. The Irkutsk pollution field is characterized by the highest content
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of lead in plant tissues. Some characteristic properties of elemental composition of the pine needles are also identified in the other pollution fields. The map of the status of pine-tree stands displays the territories with a different degree of suppression (see Fig. 2). Thus, forest stands with a high, moderate and weak suppression level were detected across an area measuring 640, more than 2 mil. and more than 5 mil. ha, respectively. Furthermore, strong suppression is recorded nearby large industrial centers and at a distance of up to 30 km from them, while moderate and weak suppression is observed from 30 to 100 km. Background (relatively undisturbed) forest stands usually are at a significant distance from the industrial centers (by 150-200 km). The highest percentage of background forest stands corresponds to the northern, southern and eastern parts of the BNT. In the southwestern (the most polluted) part of the BNT, background forest stands are detected locally – within, for example, the Goloustnaya river basin as well as at the foothills of the Eastern Sayan mountains. According to field survey and analysis of morphostructural and physiological-biochemical parameters of forest stands, the life status of background stands is influenced considerably by natural factors, including the severe climatic conditions, permafrost and seasonal permafrost, frequent forest fires, epiphytotia of micromycetes, and foci of injurious insects. It should be noted that the negative influence from noxious insects and pathogenic fungi is enhanced in forests deteriorated by industrial emissions. The overall tendency is thus: in forest stands with a strong and moderate degree of suppression, insects and micromycetes are able to enhance the deterioration of trees and accelerate the process of their destruction; usually, however, they are not the dominant injuring factor, with some exceptions, though. Specifically, in the fir forests on the northern macroslope of the Khamar-Daban macroslope, epiphytotia (pandemic fungal diseases), because of the specific character of the natural conditions, often play a determining role in the deterioration of forest stands polluted by the emissions from the Baikalsk Pulp and Paper Mill [15]. Conclusion On the basis of the approaches developed previously, we carried out targeted investigations on a regional scale which allowed us to assess with an optimal degree of detail the impact of industrial air emissions on forest ecosystems. For the first time, a comprehensive assessment of technogenic pollution of the forests throughout the Baikal natural territory, a large region in the boreal zone of Asian Russia. The findings obtained in this study indicate that the territory used in out survey has significant environment-protective and waterregulation potential, which is largely facilitated by the high level of its forestation. On the other hand, there is reason to think that the territory tends to be deteriorated considerably by technogenic emissions. Forest stands nearby industrial centers as well as those occupying extensive areas at some distance from them are experiencing adverse effects
of pollutants. In general the findings from the investigations reported in this paper lend support to the need for a continued monitoring in the interests of making well-grounded forecasts of the state of forest vegetation across polluted territories, including in the case of a change of the level and character of the emission loads. This work was done with financial support from the Russian Foundation for Basic Research (03-04-95565, 05-0497219, 05-05-97259) using equipment of the Baikal Analytical Center at the Shared Data Services Center. References 1. Present and Future of the Baikal Region. Novosibirsk: Studio Design INFOLIO, 1996, 112 p. 2. The law “About the protection of Lake Baikal”. Rossiskaya gazeta, 1999, 12 May, p. 4. 3. The “Baikal” Atlas. Moscow: Roskartografiya, 1993, 160 p. 4. Rozhkov A. S. and Mikhailova T. A. The Effect of FluorineContaining Emissions on Conifers. Berlin Heidelberg: Springer-Verlag, 1993, 142 p. 5. State Report “On the State and Protection of the environment in the Irkutsk Region in 2003”. Irkutsk: Oblmashinform, 2004, 297 p. 6. Instructions on Expedition-based Forest-Pathological Survey of the USSR’s Forests. Moscow: Gosleskhoz SSSR, 1983, 234 p. 7. The Technique for Arranging and Conducting Monitoring Operations on the USSR’s Forests. Pushkino: VNIILM, 1987, 45 p. 8. Manual on Methodologies and Criteria for Harmonized Sampling, Assessment, Monitoring and Analysis of the Effects of Air Pollution on Forests. Hamburg; Prague: United Nations Environment Programmee and Economic Commission for Europe, 1994, 477 p. 9. Pleshanov A. S. and Mikhailova T. A. The formalized method of mapping vegetation pollution by industrial air emissions. The Ecological Problems of Urbanized Territories. Irkutsk: Institute of Geography SB RAS Publisher, 1998, pp. 100-105. 10. Pleshanov A. S., Mikhailova T. A., Voronin V. I. et al. Cartographic assessment of the state of vegetation polluted by industrial air emissions from industrial centers of the Angara region. The Problems of Terrestrial Civilization. Irkutsk technical University Publisher, issue 1, pt. 1, pp. 109-113. 11. Mikhailov T. A. Influence of industrial emissions on the forests of the Baikal natural territory. Geografiya i prirod. resursy, 2003, No. 1, pp. 51-59. 12. Mikhailova T. A. The physiological condition of pine trees in the Prebaikalia (East Siberia). Forest Pathology, 2000, v. 30 (6), pp. 345-359. 13. Afanasieva L. V. Influence of Atmospheric Industrial Pollution on Pine Forests Within the Selenga River Basin: Author’s Abstract of Cand.Sc. (Biol.) Dissertation. Ulan-Ude, 2005, 19 p. 14. Mikhailova T. A., Pleshanov A. S., Berezhnaya N. S. et al. Influence of atmospheric industrial pollution on the forests of the Baikal Natural Territory. Vestn. Buryat. un-ta. Ser. 2. Biology, 2005, issue 7, pp. 193-196. 15. Morozova T. I., Oskolkova T. A. and Pleshanov A. S. The condition of fir forests of Khamar-Daban in the influence area of atmospheric emissions from the Baikalsk paper and Pulp Mill. Sib. ekol. l.. zhurn., 2005, No. 4, pp. 701-706.