UDC 551.794(282.256.341)

Pollen analysis of two dated cores of lake-marsh sediments from different regions of the Baikal basin provided the first complete record of deep changes in the lake's natural environment in the late glacial period and its significant amplitude of fluctuations in the Holocene. Pollen stratigraphy reflects the unstable state of landscapes and climate in the late Glacial and early Holocene periods. For the early - middle Holocene, the existence of an optimum is confirmed - a humid and mild climate with warm winter periods. 10 000 - 7 000 The Late Holocene of the Southern Hemisphere is identified as a period of progressive increase in climate continentality and the change of dark coniferous forests to light coniferous ones. Comparison of the variability amplitudes of Late Glacial and Holocene Paleogeographic events from our pollen records with the already known records from the Lake Baikal basin. The study of Lake Baikal and a number of other territories of Eurasia has shown that major changes in vegetation and climate are mainly associated with the melting of global ice, variations in the level of insolation and atmospheric carbon dioxide concentration. Less significant short-term fluctuations in Holocene climate and vegetation recorded in pollen records may be the response of a regional ecosystem to changes in solar activity on a quasi-thousand-year scale. Regional pollen records show a clear relationship with the climate of the Northern Hemisphere as a whole. The amplitude of these changes is higher in the north-east of the lake than in the south.

Key words: pollen analysis, paleoclimate, paleoecology, late Glacial period, Holocene, Lake Baikal basin. Baikal.

Introduction

For a correct assessment of climate changes caused by human activity and overlapping with the natural trend, it is necessary first of all to understand the direction of climate changes during the last transition period and the Holocene (Rind and Overpeck, 1993). As long as the natural dynamics of the closest to us past - Termina 1 and the Holocene, whose deposits are developed everywhere-are not reliably described and explained, it is impossible to adequately assess the degree of anthropogenic impact on the natural environment and climate. In addition, our knowledge of the closest geological past is still limited. To date, the most reliable oxygen isotope record of temperature changes in the late Glacial and Holocene periods from the Greenland ice core contains signals of sharp short-term climate variations in the late glacial period and a relatively high degree of Holocene climate stability (GRIP Members, 1995). However, data on geochemical admixture from the same core are indicators of climate instability and the Holocene proper, at least in Greenland (Mayewski et al., 1997). Significant climate variability in the Holocene was shown for many regions [Enzel et al., 1999; Wurster and Patterson; 2001; Zhao et al., 2007]; various mechanisms that determined climate changes at this time were proposed [Bond et al., 2001; Visbeck, 2002]. Present a temporal and spatial map-

The work was carried out within the framework of project N 09 - 05 - 00123-and the Russian Foundation for Basic Research and the Baikal Archaeological Project.

Fig. 1. Map-diagram of core sampling sites.

1 - Duguldzera; 2 - Dulikha; 3 - VER93 - 2, station 24 GC.

The accuracy of the late Glacial and Holocene climate, as well as the natural environment in general, is impossible without information from different regions of the planet, especially from those where the natural environment is most susceptible to climate change. Earlier studies have shown that geochemical and diatomic records from the bottom sediments of Lake Baikal were found in the same area. Lake Baikal is very sensitive to paleoclimate variations [Participants..., 1998; Khursevich et al., 2001; BDP-99..., 2005; et al.]. However, the climate reconstructions presented in the publications are based on a significantly averaged signal from deep-sea cores of lake sediments. Meanwhile, the length of the lake basin itself. Lake Baikal, which corresponds to almost 4° in latitude, and a significant difference in the parameters of the current climate in the southern and northern regions of the basin suggest differences in the trend of climate change in the past. Information about this can be obtained from the sediments of swamp ecosystems. A thick layer of organic sediments accumulated in them, storing continuous records of changes in the natural environment with high time resolution for the last 5-15 thousand years (Kataoka et al., 2003; Bezrukova, Krivonogov, Abzaeva et al. Bezrukova, Belov, Abzaeva et al., 2006; Bezrukova, Belov, Letunova et al., 2008; Bezrukova, Krivonogov, Takahara et al., 2008]. The study of these records showed that climate variability in the Holocene, despite a weaker range than during the last glaciation, was more significant in amplitude and more often in time than is usually recognized.

The purpose of this article is to conduct a high - resolution reconstruction of the variability of the natural environment of the Baikal Basin in the late Glacial and Holocene periods using the example of dated pollen records from swamp massifs currently located in areas with different bioclimatic parameters: from the southern and north-eastern shores of the lake. Both territories were practically unaffected by anthropogenic impact until the middle of the 17th century, so sedimentation records from these ecosystems will reflect the natural dynamics of the natural environment.

Study areas

Duguldzer. The core of the Duguldzer was selected on the eastern coast of Lake Baikal (Fig. 1), in the area of forest ecosystems of the mid-mountain relief. The ecosystems are dominated by larch, pine and cedar forests. Higher up on the mountain slopes and in the valleys, larch-cedar-spruce forests are located, which are replaced up the profile by cedar-fir rare-coniferous, mainly valley forests. The climate in this area is sharply continental. The average temperature in January, according to the nearest weather station Davsha, is -22 °C, July - +14 °C, the average annual temperature is -3.3 °C. The average annual precipitation varies from 350 to 400 mm. Permafrost of the island type is widespread on the territory (Baikal..., 1993).

Dulikha. The peat massif is located on the southern coast of the lake (Fig. 1), where the South Siberian taiga of Siberian cedar and fir prevails. Larch is rare in wetlands. Birch forms derived forests, replacing dark coniferous forests in the areas of clearings and harems. The territory's climate is temperate continental [Ibid.]. The average temperatures of July, January and the year are +14.4, -17.7 and -0.7 °C, respectively. The average annual precipitation is 600 - 650 mm. Thus, the difference in the values of modern indicators of the average January temperature in the studied territories is 4 - 5 °C, the average July temperature is approx. 2 °C, average annual temperature - approx. 2.5 °C, average annual precipitation - almost 250 mm.

Materials and methods

The core length of the Duguldzer is 400 cm. The upper 330 cm are represented by peat of different composition, the lower 70 cm are formed by lake gittia with an admixture of clay-sized mineral particles. Every fourth santi was studied by pollen analysis-

This provided an average time resolution of 150-200 years. The age model of the section is based on seven radiocarbon dates.

The thickness of Late Glacial and Holocene peat deposits in the Dulik core is 500 cm (Bezrukova, Krivonogov, Abzaeva et al., 2005). Every fourth centimeter was studied by pollen analysis. The average time resolution of recording is 100-150 years. The age model of this section is provided with three dates (see the table).

The palynozone chronological framework is calculated by linear interpolation between dates. To assess possible mechanisms that determined vegetation shifts in the territory and correlate the time boundaries of these shifts with those in the Northern Hemisphere, radiocarbon age values were converted to calibration values using the CalPal software package [Danzeglocke, Joris, and Weninger, 2008]. On the pollen charts, the age scales of the sections are given in a calibrated calculation.

The biome reconstruction method was used to calculate the pollen heat and humidity indices and the formula for calculating the indices [Prentice et al., 1996; Tarasov et al., 2000; Demske et al., 2005].

Pollen charts are presented in the most generalized form possible due to the following reasons:: 1) the complete diagram of the Dulikh section has already been published [Bezrukova et al., 2005], but the dates in the publication were given in conditional ¹⁴ C-values, without calibration of the results, as well as pollen indices of heat and moisture; 2) the complete diagram for the Duguldzer section is given in the article: [Abzaeva et al., 2008]; 3) for the purposes of this paper, it is more important to show not so much the diagrams themselves, but rather the indices of changes in various parameters of the natural environment obtained on their basis. The zones identified in the diagrams are interpreted in a complex way from the point of view of both vegetation and climate dynamics, so they are called bioclimatic zones; for Duguldzer, the designation is Dz, for Dulikhi-Dl.

Research results and their interpretation

The pollen diagram of the Duguldzer section shows four zones (Fig. 2). The description is given from bottom to top. The zones are characterized by the most important pollen taxa for reconstructions.

Dz4-Artemisia-Betula alba-type-Picea: >16,000 bp; depth 400 - 385 cm. The sediments are represented by highly mineralized gittia. The spore-pollen spectra (hereinafter referred to as SPS) show the first maximum of pollen from Picea obovata spruce and Betula sect birches of both sections. Albae, Betula sect. Nanae. The grass pollen group is dominated by Artemisia wormwood pollen.

Dz3d - Artemisia-Salix-Betula alba-type-meadow-steppe mixed grasses. ~16 000 - 14 700 BP; depth 385-355 cm. SPS are formed in the lake mantle. Tree birch pollen prevails along with the pollen of shrub birch, willow and mesoxerophytic mixed grasses.

Dz3g-Betula alba-type-Cyperaceae-Salix: ~14 700 - 14 000 l. n.; 355-345 cm). The spectra are dominated by birch and willow pollen, and there is a lot of sedge pollen.

Results of radiocarbon dating of sediments

* The dating was performed by accelerator mass spectrometry at the Chronological Research Center of Nagoya University, Japan.

2. Pollen diagram of Duguldzer peat bog deposits.

* Here and further in the column "Pollen indices", the thick line corresponds to the change in the heat index, the thin line corresponds to the change in the moisture index.

Dz3b - Duschekia-Picea - Larix-Betula alba-type-Equisetum. -14 000 - 13 200 l. n.; 345-325 cm. SPS zones accumulated in the mantle. Spruce pollen reappears in the SPS and the abundance of alder pollen increases.

Dz3b - Larix-Betula alba-type-Duschekia. ~13 200 - 12 800 l. n.; 325-315 cm. SPS is characterized by the second and most significant maximum of spruce pollen. The sediments are represented by a transition layer from mantle to peat.

Dz3a-Picea - Duschekia-Betula alba-type ~12 800 - 11 300 The spectra of the zone were formed already in peat deposits. The spectra are characterized by the most significant maxima of birch and alder pollen.

Dz2b - Larix-Betula alba-type-Picea - Polypodiophyta. ~11 300 - 10 000 l. n.; 265-225 cm. A lot of larch and birch pollen, the first maximum of fern spores and sedge pollen. The abundance of spruce pollen is constantly changing. At the beginning of the zone, the maximum pollen of hygrophytes of the genus Potamogeton and Typha was observed.

Dz2a - Abies - Larix-Picea-Betula. ~10 000 - 6 000 l. n.; 225-110 cm. Fir pollen is constantly present against the background of a decrease in the abundance of spruce pollen, with a slight but constant presence of Siberian pine pollen, an increased abundance of pollen about the sap and spores of ferns and horsetails.

DZ1B-Pinus sylvestris-Pinus sibirica - Pinus pumila; ~6000-2500 BP; 110-55 cm. The SPS zone is characterized by a predominance of pollen from both pines and cedar elfin.

DZ1A-Larix-Pinus sylvestris - Pinus sibirica-Pinus pumila-Betula papa-type; ~2,500-0 bp; 55-0 cm. The SPS zone is characterized by a second maximum of shrubby birch pollen, an increase in the abundance of high birch pollen, and sphagnum moss spores.

The pollen diagram of the Dulich section shows four zones (Fig. 3). The description is given from the bottom up.

DL4-Larix-Picea-Salix-Betula Papa-type-Betula alba-type >13,200 bp; 500-480 cm. The SPS is dominated by the pollen of shrubs and grasses. The pollen group of woody plants is dominated by spruce, larch, and birch pollen from both sections.

Dl3 - Artemisia - Larix-Picea-Betula nana-type-Betula alba-type-Cyperaceae - Polypodiophyta. -13 200 - 10 600 l. n.; 480-405 cm. The SPS continues to be dominated by pollen from shrubs and grasses. In the composition of the pollen of woody plants, the predominance passed to the pollen of birch and larch. The abundance of pollen from mesoxerophytic mixed grasses, grasses, sedges, and fern spores increased.

Dl2b-Abies-Picea-Betula alba-type ~10 600 - 10 000 l. n.; 405-370 cm. In SPS, the abundance of tree pollen in general has increased, and fir pollen has appeared-

3. Pollen diagram of the Doolikha peat bog deposits.

you, Siberian pines, scots pines and cedar elfin.

Dl2b-Pinus sibirica-Betula alba-type-Abies. ~10 000 - 9 200 l. n.; 370-330 cm. The spectra are dominated by fir pollen, and the abundance of pollen from both pines increases.

D12a-Abies-Pinus sibirica-Betula alba-type ~9 200 - 6 200 l. n.; 330-215 cm. The content of fir pollen is steadily decreasing, and the abundance of Siberian and Scots pine pollen continues to increase. The abundance of birch pollen is almost unchanged.

Dl1-Pinus pumila-Betula-Pinus sylvestris -Pinus sibirica; ~6200-0 BP; 215-0 cm. The Siberian pine pollen abundance reached a maximum, the scots pine pollen abundance continued to increase, and the birch pollen abundance decreased. Many spores of sphagnum mosses appeared.

Discussion of the results: reconstruction of the paleoenvironment

Pollen records and radiocarbon dating of lake-marsh sediments allowed us to reconstruct changes in vegetation and climate, and partly in the hydrological regime of the southern and northeastern shores of Lake Baikal after the maximum of the last glaciation.

Late glacial vegetation and climate

The pollen record from Duguldzer covers a longer time interval than the record from Dulikha. Based on the results of the palynological study of the Duguldzer core, the continuous dynamics of vegetation and climate change in the transition period from the last glaciation to the modern interglacial period were reconstructed for the first time for the entire Baikal basin.

The lowest part of the Duguldzer pollen record, up to 16,000 BP (Dz4), reflects the natural conditions for the formation of mineralized mantle in an overgrown lake on the site of a swamp massif. At that time, the northeastern coast was dominated by forest-tundra vegetation of larch, birch, spruce, and grass-shrub tundra. An analog of such vegetation is currently found in the Pechora River Delta, where a cold climate is noted with an average annual temperature of approx. -4 °C, an average July temperature of approx. +13 °With an average annual precipitation of about 400 mm (Valiranta, Kaakinen, and Kuhry, 2003). The time of vegetation existence coincides with the beginning of deglaciation after ~17,000 BP (Bowen et al., 2002) and with relative warming. The heat and humidity indices indicate that cold (especially in winter) and wet weather persisted

climate. At the same time, judging by the vegetation composition, the humidity index characterizes high soil humidity due to the melting of permafrost, and low summer temperatures, rather than high values of the amount of precipitation. Almost complete disappearance of spruce pollen simultaneously with a decrease in the abundance of tree pollen in the spectra formed in the mineralized mantle ~16 000 - 14 700 L. N., and the predominance of pollen from birch of both sections, willow, and mesoxerophytic mixed grasses indicate a deterioration in the conditions for the existence of forest vegetation (Dz3d). This may have been caused by a general deterioration of the climate during one of the terminal 1 stadials, the pessimum of which occurred ~15,500 BP (Wehrli and Tinner, 2007). Heat and moisture indexes show a decrease in the level of heat and moisture available to plants. The heat index has slightly increased ~14 700 - 14 000 It coincided with the first significant warming of terminal 1, and humidity continued to decline. The vegetation composition was dominated by shrubby yernik and willow tundras with areas of birch woodlands. The appearance of the first significant maximum of sedge pollen suggests the initiation of local swamp formation. In the interval ~14 000 - 13 200 near the lake, forest-tundra vegetation is distributed first with larch, and then with spruce, birch, and alder. The same time on the southern coast of Lake Baikal (previously -13,200 BP) was marked by the predominance of birch-spruce woodlands with larch; it corresponded to the conditions of climate mitigation of interstadial warming, similar in time to the manifestation of alleredu. The short-term culmination of heat and moisture in the Duguldzera area refers to the period of -13 200 - 12 800 l. n. (Dz3b); it led to the expansion of spruce. In the south of the lake, spruce also dominated at this time. A new stage of reducing the level of heat and instability of humidification took place ~12 800 - 11 300 l. n. (Dz3a). At that time, the north-eastern coast was dominated by spruce-birch forest tundras and alder tundras. Unfavorable conditions for the existence of forest vegetation were probably a consequence of climate deterioration during the period similar in time to the Late Dryas [Dansgaard et al., 1993]. At about the same time, the climate in the south of the lake became more continental, which led to the development of birch-larch forest tundra with spruce and grass-shrub tundra (D13). Pollen indices indicate the maximum moisture content for the entire studied period and the minimum level of heat supply. The appearance of vegetation supports the idea of high soil moisture (thawing permafrost) due to low summer temperatures (low evaporation). This period in the south of the lake was longer and lasted until almost 10,600 years ago.

Vegetation and climate of the Holocene humidity optimum

Since the beginning of the Holocene (~11 300 - 10 000 Dz2b) ) in the north-east of Lake Baikal, a low-lying sedge swamp has formed on the site of an overgrown lake. Around the Duguldzer swamp massif, the positions of larch and spruce have strengthened. On the south coast, on the contrary, the area of larch trees decreased at this time, but the area of fir trees began to expand quite quickly. Such shifts in vegetation composition indicate a softening of continentality, an increase in the annual amount of precipitation and the average temperature of the winter seasons. These changes led to the beginning of the expansion of the moist fir taiga, which means that the Holocene humidity optimum began on the southern coast. The maximum development of the fir taiga took place here ~10 000 - 9 200 l. n. (Dl2b). The completion of the Holocene humidity optimum on the southern coast occurred gradually-from -9,200 to ~6,800 BP (Dl2a). The northeastern coast of Lake Baikal is characterized by a different manifestation of the humidity optimum and its chronological boundaries. Here, the beginning of the moisture optimum occurred later than 10,000 years ago, and its maximum corresponded to ~7 000 - 6 000 L. N. (maximum abundance of fir pollen). However, despite such a significant difference in the time of the optimal moisture onset, its completion in both the north-east and south of Lake Baikal occurred between 7 000 - 6 000 Previously reconstructed on the basis of a pollen record from the bottom sediments of Lake Baikal (VER93-2, station 24 GC (see Fig. 1) quantitative climate characteristics the Holocene moisture maxima showed that ~9 500 - 6 500 The average annual precipitation exceeded the current values by 80-100 mm, and the average winter temperatures were 2-4 °C higher than the current values. At the same time, the average temperature in July could be almost the same as today's [Tarasov et al., 2007]. The combination of mild, snowy winters with no spring frosts, cool and humid summers ensured the development of dark coniferous fir forests. The nature of the variability of pollen indices shows a steady trend of decreasing humidity and increasing heat. 10 000 - 6 000 L. N. in the north-east and 10 500 - 7 000 L. N. in the south of the lake. As the relative values of heat and moisture approach the current level, the dominance of the fir taiga ends.

In general, the Holocene optimum should be considered as a very important interval from the point of view of drawing analogies with it of possible climate changes in the future. Usually, the optimum is attributed to the time of maximum postglacial warming (Winkler and Wang, 1993), which is characterized by warm and generally stable climate.

humid climate in Northern Europe. But, for example, in China, as in the Baikal basin, the Holocene optimum is defined as the period of maximum precipitation totals rather than maximum heat (Xiaoqiang Li et al., 2004; Porter and Weijian, 2006). The softening of the continental climate and the onset of the fir forest phase in the Baikal basin could be the result of an increase in the temperature gradient between the ocean and land, which led to increased transport of moist air masses to the continent, reaching even the lake basin and contributing to an increase in the level of convective precipitation here. The Holocene optimum with a humid and cool climate is found in a wide variety of paleoclimatic records for almost the entire Northern Hemisphere (Herzschuh et al., 2005; Blyakharchuk et al., 2004; Mudie et al., 2007). New confirmation that approx. 11 000 - 7 000 The highest level of atmospheric precipitation and a low-continental climate with cool summer and warm winter seasons were recorded in Western Transbaikalia (Bezrukova, Krivonogov, Takahara et al., 2008).

Vegetation and climate of the post-optimal Holocene period

In the interval ~7 000 - 6 000 in the south and after ~6 000 AD in the north-east of the lake, the composition of forest vegetation radically changed: Siberian pine, scots pine, and larch replaced fir and spruce. The shift in the composition of woody plants occurred under conditions of a significant decrease in moisture content and an increase in heat. Moreover, the ecological and edaphic requirements of new elements of forest vegetation suggested an increase in the continental climate due to a significant decrease in atmospheric humidity and average temperature in winter seasons, and an increase in summer seasons (Tarasov et al., 2007). The end of the humidity optimum in the Baikal basin coincided with the onset of the neoglacial period on the Loess Plateau (Porter and Weijian, 2006), with the well-known peak of North Atlantic drifting ice ca. 6,000 years ago (Bond et al., 2001). At about the same time (~5,500 BP), the relatively cool and humid "green" period in North Africa, which provided, for example, the existence of numerous lakes within the territory of the modern Sahara Desert, also ended (Renssen et al., 2006). Transition of the climate system in almost the entire territory of Eurasia to a significantly more stable climate system. This signified the global spread of this phenomenon and the presence of global mechanisms that caused it. Landscapes of the Baikal basin responded to changes in the global climate by radically rearranging their structure and composition: dark coniferous mesophytic forest vegetation of the early - Middle Holocene was replaced by light coniferous, significantly more xerophytic, forest vegetation of the late Holocene. Starting from about 6 000 AD, the level of moisture available to plants shows a steady downward trend with minor fluctuations, and the relative values of the heat level are characterized by a trend of frequent and small fluctuations near its current values (see pollen indices in Figures 2, 3). Consequently, the level of heat and moisture did not remain constant; this indicates instability and in the late Holocene. The frequency and amplitude of these fluctuations require further study, although it is clear from the presented records that these climate shifts had an impact on the landscapes of the Baikal ecosystem. But the changes that took place were expressed rather in the variability of local landscapes. In the Late Holocene, ca. 2,400, 500 BP. on the southern shore of the lake, the swamp's hydrological regime was variable, which occurred with a decrease in the level of heat. Moreover, after 2,400 AD, the expansion of cold glacial associations began here. On the north-eastern coast of Lake Baikal, this phenomenon became even more pronounced (ca. 2,500 bp Determination of a clear pollen signal of climate deterioration and development of glaciers in the lake basin as well. Kotokel (Bezrukova, Krivonogov, Takahara et al., 2008) suggests that the response of the entire Baikal ecosystem to a decrease in solar activity occurred after 2,700 BP, when climate deterioration occurred in both hemispheres (Swindles, Plunkett, Roe, 2007). Even shorter time fluctuations in the landscape and climate situation in the Baikal basin, which coincided in time with known paleogeographic events, such as the medieval optimum and the Little Ice Age, are known from pollen records of the northern coast of the lake (Bezrukova, Belov, Abzaeva et al., 2006).

Conclusion

The results of palynological and radiocarbon studies of lake and marsh ecosystems on different coasts of Lake Baikal, as well as their comparison with available dated records of changes in the natural environment in neighboring regions, provided a detailed, geochronologically reliable record of the variability of the natural environment of the lake basin since the end of the last glaciation maximum. 17 000 - 16 000 Significant shifts in the atmospheric circulation system of the Northern Hemisphere early deglaciation contributed to the onset of relatively warm and dry summers 16,000-

12,000 BP in Siberia (Schirrmeister et al., 2002). It was at this time that the formation of peat deposits proper began on the southern and northeastern coasts of Lake Baikal: approximately 13,000 and 11,500 bp, respectively. In general, the high-resolution pollen records presented in this article indicate profound changes in the vegetation and climate of the lake basin in the late Glacial - early Holocene and the high variability of the climate of the modern interglacial proper. Pollen records show the unstable state of landscapes and climate in the late Glacial and Early Holocene, as well as frequent changes in plant associations. The reason for such shifts could be the destruction of cover and mountain glaciers, which led to the instability of the ocean-atmosphere-cryosphere system. Pollen records confirm the onset of a long Holocene optimum period with a humid and mild climate, with warm winter periods of approx. 11 000 - 10 000 The southern part of Lake Baikal is dominated by spruce-cedar-fir forests in various regions of the Baikal basin under conditions of increased insolation in the high latitudes of the Northern Hemisphere. Completion of the optimal period took place ~7 000 - 6 000 L.this coincided with a decrease in the level of insolation, the establishment of the current level of the World Ocean. The optimum was followed by a period of progressive strengthening of the continental climate - a decrease in the amount of precipitation, the average temperature of the winter seasons, and an increase in summer air temperatures. As a result, dark coniferous forests were replaced by light coniferous ones. Such a significant climate shift is mainly associated with changes in the level of solar radiation and the concentration of atmospheric carbon dioxide. Less significant, short-term variations in Holocene climate and vegetation ca. 2 500 - 2 400, 1 200 - 1 600, 500 - 400 The solar deposits recorded in our pollen records may be a response of the regional ecosystem to the variability of solar activity on a quasi-thousand-year scale (Meeker and Mayewski, 2002). Records from the Doolich and Duguldzer sections show a fairly strong relationship with climate variations in the Northern Hemisphere as a whole. The amplitude of these changes is higher in the north-east of the lake than in the south. In addition to climate, local factors (features of the geological and geomorphological structure of the territory and vegetation cover, changing ground water levels, variations in the thickness and depth of the permafrost layer) actively controlled the history of the region's natural environment.

New, higher-resolution records with more detailed chronological control are needed to confidently recognize small, age-old variations in the variability of the South coast's natural environment.

List of literature

Abzaeva A. A., Bezrukova E. V., Letunova P. P., Belov A.V. Detailed paleoclimatic reconstruction of the Late Glacial and Holocene periods of the northeastern coast of Lake Baikal based on palynological data. - 2008. - T. 49, N 10/11. - pp. 375-379.

Baikal: Atlas, Moscow: Federal Service of Geodesy and Cartography, 1993, 160 p.

Bezrukova E. V., Belov A.V., Abzaeva A. A., Letunova P. P., Orlova L. A., Kulagina N. V., Fischer E. E. First high-resolution dated records of vegetation and climate changes in the Middle-Late Holocene of the northern coast of Lake Baikal. Baikal / / Doklady RAN, 2006, vol. 411, N2, pp. 254-258.

Bezrukova E. V., Belov A.V., Letunova P. P., Abzaeva A. A., Kulagina N. V., Fischer E. E., Orlova L. A., Shafer E. V., Voronin V. I. Biostratigraphy of peat deposits and climate of the northwestern part of the mountain frame of Lake Baikal in the Holocene. - 2008. - T. 49, N 6. - pp. 547-558.

Bezrukova E. V., Krivonogov S. K., Abzaeva A. A., Letunova P. P., Orlova L. A., Takahara Kh., Miyoshi N., Nakamura T., Krapivina S. M., Kawamuro K. Landscapes and climate of the Baikal region in the Late Glacial and Holocene period based on the results of complex studies of peat bogs. - 2005. - V. 46, N 1. - pp. 21-33.

Bezrukova E. V., Krivonogov S. K., Takahara Kh., Letunova P. P., Shichi K., Abzaeva A. A., Kulagina N. V., Zabelina Yu. S. Lake Kotokel-a reference section of the Late Glacial and Holocene of the South of Eastern Siberia / / Doklady AN. - 2008. - Vol. 420, n 2. - P. 248 - 253.

Participants of the Baikal-Drilling project. Continuous recording of paleoclimate changes over the last 5 million years from the bottom sediments of Lake Baikal. - 1998. - Vol. 39, N2. - pp. 135-154.

BDP-99 Baikal Drilling Project Members. A new Quaternary record of regional tectonic, sedimentation and paleoclimate changes from drill core BDP-99 at Posolskaya Bank, Lake Baikal // Quaternary International. - 2005. - Vol. 136. -P. 33 - 48.

Blyakharchuk T.A., Wright H.E., Borodavko P.S., Knaap W.O. van der, Ammann B. Tate Glacial and Holocene vegetational changes on the Ulagan high-mountain plateau, Altai Mountains, southern Siberia // Palaeogeography, Palaeoclimatology, Palaeoecology. - 2004. - Vol. 209. -P. 259 - 279.

Bond G., Kromer В., Beer J., Muscheler R., Evans M.N., Showers W., Hoffmann S., Lotti-Bond R., Hajdas I., Bonani G. Persistent solar influence on north Atlantic climate during the Holocene // Science. - 2001. - Vol. 294. - P. 2130 - 2136.

Bowen D.Q., Phillips E.M., McCabe A.M., Knutz P.C., Sykes G.A. New data for the last glacial maximum in Great Britain and Ireland // Quaternary Science Review. - 2002. -Vol. 21. - P. 89 - 101.

Dansgaard W., Johnson S.J., Clausen H.B., Dahl-Jensen D., Gundestrup N.S., Hammer C.U., Hvidberg C.S., Steffensen J.P., Sveinbjurnsdottir A.E., Jouzel J., Bond G. Evidence for general instability of past climate from a 250-kyr ice core record // Nature. - 1993. - Vol. 364. - P. 218 - 220.

Danzeglocke U., Joris O., Weninger B. CalPal-2007 ^online URL: http://www.calpal-online.de (accessed: 27.05.2008).

Demske D., Heumann G., Granoszewski W., Nita M., Mamakowa K., Tarasov P.E., Oberhansly H. Late Glacial and Holocene vegetation and regional climate variability evidenced in high-resolution pollen records from Lake Baikal // Global and Planetary Change. - 2005. - Vol. 46. - P. 255 - 279.

Enzel Y., Ely L.L., Mishra S., Ramesh R., Amit R., Lazar B., Rajaguru S.N., Baker V.R., Sandler A. High resolution Holocene environmental changes in the Thar Desert, northwestern India // Science. - 1999. - Vol. 284. - P. 125 - 128.

GRIP Members. Climate instability during the last interglacial period recorded in the GRIP ice core // Nature. -1995. -Vol. 364. - P. 203 - 207.

Herzschuh U., Zhang C., Mischke S., Herzschuh R., Mohammadi E., Mingram B., Kurschner H., Riedel F. A late Quaternary lake record from the Qilian Mountains (NW China): evolution of the primary production and the water depth reconstructed from macrofossil, pollen, biomarker, and isotope data // Global and Planetary Change. -2005. -Vol. 46. -P. 361 - 379.

Kataoka H., Takahara H., Krivonogov S., Bezrukova E., Orlova L., Krapivina S., Kawamuro K. Pollen Record from the Chivyrkui Bay Outcrop on the Eastern Shore of Lake Baikal since the Late Glacial // Long Continental Records from Lake Baikal. - Tokyo: Springer Verlag, 2003. - P. 207 - 218.

Khursevich G.K., Karabanov E.B., Prokopenko A.A., Williams D.F., Kuzmin M.I., Fedenya S.A., Gvozdkov A.N., Kerber E.V. Insolation regime in Siberia as a major factor controlling diatom production in Lake Baikal during the past 800,000 years // Quaternary International. - 2001. - Vol. 80/81. -P. 47 - 58.

Mayewski P.A., Meeker L.D., Twichler M.S., Whitlow S., Yang Q., Lyons W.B., Prentice M. Major features and forcing of high-latitude Northern Hemisphere atmospheric circulation using a 110000 year long glaciochemical series // J. of Geophysical Research. - 1997. - Vol. 102, N 263. -P. 45 - 66.

Meeker L.D., Mayewski P.A. A 1400-year high-resolution record of atmospheric circulation over the North Atlantic and Asia // The Holocene. - 2002. - Vol. 12. - P. 257 - 266.

Mudie P.J., Marret E., Aksu A.E., Hiscott R.N., Gillespie H. Palynological evidence for climatic change, anthropogenic activity and outflow of Black Sea water during the late Pleistocene and Holocene: Centennial- to decadal-scale records from the Black and Marmara Seas // Quaternary International. -2007. -Vol. 167/168. -P. 73 - 90.

Porter S.C., Weijian Z. Synchronism of Holocene East Asian monsoon variations and North-Atlantic drift-ice tracers // Quaternary Research. - 2006. - Vol. 65. - P. 443 - 449.

Prentice I.C., Guiot J., Huntley В., Jolly D., Cheddadi R. Reconstructing biomes from palaecological data, a general method and its application to European pollen data at 0 and 6 ka // Climate Dynamics. - 1996. - Vol. 12. - P. 185 - 194.

Renssen H., Brovkin V., Fichefet T., Goosse H. Simulation of the Holocene climate evolution in Northern Africa: the termination of the African Humid Period // Quaternary International. - 2006. - Vol. 150. - P. 95 - 102.

Rind D., Overpeck J. Hypothesized causes of decade-to-century-scale climate variability: climate model results // Quaternary Science Reviews. - 1993. -Vol. 12. -P. 357 - 374.

Schirrmeister L., Siegert C., Kuznetsova Т., Kuzmina S., Andreev A., Kienast F., Meyer H., Bobkov A. Paleoenvironmental and paleoclimatic records from permafrost deposits in the Arctic region of Northern Siberia // Quaternary International. - 2002. - Vol. 89. - P. 97 - 118.

Swindles G.T., Plunkett G., Roe H.M. A delayed climatic response to solar forcing at 2800 cal. BP: multiproxy evidence from three Irish peatlands // The Holocene. - 2007. - Vol. 17, N2. -P. 177 - 182.

Tarasov P., Bezrukova E., Karabanov E., Nakagawa Т., Wagner M., Kulagina N., Letunova P., Abzaeva A., Granoszewski W., Riedel E. Vegetation and climate dynamics during the Holocene and Eemian interglacials derived from Lake Baikal pollen records // Palaeogeography, Palaeoclimatology, Palaeoecology - 2007. - Vol. 252. - P. 440 - 457.

Tarasov R.E., Volkova V.S., Webb T., Guiot J., Andreev A.A., Bezusko L.G., Bezusko T.V., Bykova G.V., Dorofeyuk N.I., Kvavadze E.V., Osipova I.M., Panova N.K., Sevastyanov D.V. Last glacial maximum biomes reconstructed from pollen and plant macrofossil data from northern Eurasia // J. of Biogeography - 2000. - Vol. 27. - P. 609 - 620.

Valiranta M., Kaakinen A., Kuhry P. Holocene climate and landscape evolution East of the Pechora Delta, East-European Russian Arctic // Quaternary Research. - 2003. -Vol. 59. - P. 335 - 344.

Visbeck M. The ocean's role in Atlantic climate variability // Science. - 2002. - Vol. 297. - P. 2223 - 2224.

Wehrli M., Tinner W. Ammann B. 16 000 years of vegetation and settlement history from Egelsee (Menzingen, central Switzerland) // The Holocene. - 2007. - Vol. 17, N6. -P. 747 - 761.

Winkler M.G., Wang P.K. 1993. The late-Quaternary vegetation and climate of China // Global Climates Since the Last Glacial Maximum. - Minneapolis: University of Mnnesota Press, 1993. -P. 221 - 264.

Wurster C.C., Patterson W.R. Late Holocene climate change for the eastern interior United States: evidence from highresolution d180 value of marital otoliths // Palaeogeography, Palaeoclimatology, Palaeoecology. - 2001. - Vol. 170. -P. 81 - 100.

Xiaoqiang Li, Zhou Jie, Shen Ji, Weng Chengyu, Zhao Hongli, Sun Qianli. Vegetation history and climatic variations during the last 14 ka BP inferred from a pollen record at Daihai Lake, north-central China // Review of Paleobotany and Palynology - 2004. - Vol. 132. - P. 195 - 205.

Zhao Y., Cheng Yu Z., Chen E., Ito E., Zhao С. Holocene vegetation and climate history at Hurleg Lake in the Qaidam Basin, northwest China // Review of Palaeobotany and Palynology. - 2007. - Vol. 145. - P. 275 - 288.

The article was submitted to the Editorial Board on 26.09.08.

Permanent link to this publication: