The evolution of soils of the taiga forest-steppe ecotone of the Baikal region during the Holocene

Geography and Natural Resources 30 (2009) 324–331

The evolution of soils of the taiga forest-steppe ecotone of the Baikal region during the Holocene L. V. Danko * Institute of Geography SB RAS, Irkutsk Received 24 December 2008

Abstract The territorial specific character of the main stages of Holocene pedogenesis is demonstrated. The study uncovers the characteristic features of bioclimatic evolution of chernozemic and texture-differentiated soils of the Mid-Holocene into organo-accumulative (soddy) soils typical of contemporary landscapes. For the Mid-Late Holocene five stages of soil formation have been identified, which are interrupted by an intensification of denudation-accumulative processes as a consequence of global coolings. Keywords: soil evolution, landscape-climatic changes, Holocene, taiga forest-steppe ecotone, Baikal region.

Formulation of the problem The general course of regional landscape-climatic changes during the Holocene in the Baikal region has been reconstructed to date and detailed in [1–3]. Most palaeogeographical reconstructions rely on biostratigraphic data, even though a large number of publications are devoted to the issues relating to the region’s soil evolution during the Late Pleistocene and Holocene [4–6]. At the same time there is a scarcity of data on the properties of soils, structural changes in soil cover, and the directedness and rate of soil formation processes for that period. To this we can add the extremely scant current evidence regarding the soil formation characteristics under different landscape conditions on different landforms. Undoubtedly one of the reasons behind the scantiness of palaeopedological information has to do with the poor persistence of palaeosoils in conditions of mountain topography, and with the relatively unstable tectonic situation. Another reason is that the greater part of the sections under investigation occurs immediately at Baikal’s terraces, and on the shores of the bays and gulfs of Lake Baikal. Of particular importance for palaeogeographical and palaeolandscape reconstructions are the sections in which uneven-aged soils in the vertical profile alternate with sedimentary rocks of a different genesis. In essence, buried soils and stratigraphic sequences of Quaternary sediments represent

* Corresponding author. E-mail address: [email protected] (L. V. Danko)

two interacting types of record of information on temporal changes in natural environment [7, 8]. An integral, comprehensive study of them makes it possible, on the one hand, to reconstruct the properties of soils and the character of soil formation, and, on the other, to reconstitute the appearance of palaeolandscapes, characterize situations and processes of sedimentation, and to identify palaeogeographical events. Objects and methods of investigation The investigations were made on the western shore of Lake Baikal within the foothills areas of the Primorsky Range, the Priolkhonskoye plateau and the Kuchelga-Talovskaya depression separating them (Fig. 1). Given the Baikal region’s continentality of climate, the study area is generally characterized by the most arid conditions because of the manifestation of the barrier-shadow and piedmont-depression landscape-forming effects under the influence of the main orographic landforms, namely: the Primorsky Range and the Baikalsky Range which formed during the Pliocene-Early Quaternary period. The territory is shielded by these mountain ranges from northwesterly moisture-carrying winds. The present-day climate is notable for its anti-cyclonic regime, insufficient atmospheric humidification (100–250 mm/year), a short growing period (4–4.5 months), and for winters with little snow. The mean air temperature for January and July, respectively, is –17.3 and 14.4 оС, and the yearly mean temperature is –0.7 оС [9]. Three sections were selected for reconstructing the soil formation history during the Holocene. The Kuchelga sec-

Copyright © 2009 IG SB, Siberian Branch of RAS. Published by Elsevier B.V. All rights reserved doi:10.1016/j.gnr.2009.11.004

L. V. Danko / Geography and Natural Resources 30 (2009) 324–331

Fig. 1. The study area (hatched).

tion was established on a deluvial apron of the northwestern slope of the Kuchelga-Talovskaya depression, the Kharga section was installed in the foothills area of the Primorsky range on a planate watershed surface, and the Kulura section was placed in the upper part of a gently sloping depression between ridges. The foothills area of the Primorsky Range and the Kuchelga-Talovskaya depression is distinguished by a complexity and contrast of contemporaneous landscape pattern which are determined not only by the natural course of evolution of ecosystems but also by the characteristics of their economic utilization [10–12]. The appearance of the territory is governed by piedmont-taiga broken and open pine-larch and larch forests with the inclusion of Daurian rhododendron, Duschekia fruticosa, black cotoneaster, and Spiraea media with true moss-sedge, forbs-sedge and, more rarely, grassforbs soil cover. Steppe species have a significant occurrence in the soil cover on the southern and southwestern slopes. In felled and burned-over areas there occur secondary birch and aspen shrubs forests. Steppe grass and grass-forbs facies occur in patches on the southern and southeastern slopes, on the slope aprons, and along intermontane small river valleys as well as at places of piedmont-taiga geosystems that were destroyed as a result of the economic activities and wild fires. Xerophytic steppe communities prevail on the slopes surrounding Baikal, and in the vicinities of human settlements. The differentiation of soil cover is determined by the territory’s landscape characteristics, specifically by exposure factors, and by the non-uniformity of geological-geomorphological conditions which is complicated by an alternation of subvertically occurring earth materials resistant and non-

325

resistant to weathering. Contemporaneous soils have largely a weakly developed, thin, strongly and moderately stony profile. Every so often the slopes and watersheds exhibit rock outcrops. The structure of soil cover in the foothills area of the Primorsky Range is dominated by organic-accumulative grey-humic (soddy) soils [13]. The northern slopes of the Kuchelga-Talovskaya depression are notable for a contrasting complex composition of soil cover with replacement (from watershed to piedmont) of typical petrozems and humic petrozems by light- and grey-humic lithozems, and by organic-accumulative grey-humic soils. The southern slopes are typified by a weakly contrasting complex composition and a different sequence of soils in the catena: humic petrozems – light-humic lithozems – organic-accumulative light-humic soils. Humic carbo-petrozems and grey-humic carbo-lithozems are produced on compact calcareous earth materials. Polygenetic dayside, fossil and buried soils usually occur in the lower parts of the slopes, aprons, creek valleys and valleys, and more rarely in the near-watershed areas of the slopes. About thirty different methods are currently used in the study of palaeosoils [14–17]. This paper is based on the genetic analysis of sediments and soils, and their relict attributes. For reconstructing the character of soil formation, in addition to analyzing stable diagnostic attributes (consistency, grain-size composition, distribution and type of neoformations, color, structure, jointing, traces of cryogenic processes, etc.), the exchange bases, the bulk elemental composition of soils and sediments, and the fractional-group composition of humus have been determined. This research has used generally accepted techniques [18, 19]. Radiocarbon dating of soils made it possible to analyze the data obtained at time intervals of 500–1500 years. The radiocarbon age dating of soils was carried out at the Laboratory of Geology and Palaeoclimatology of the Cainozoic of the Institute of Geology and Mineralogy SB RAS (Novosibirsk) from humic acids. The radiocarbon dates were calibrated using the “CalPalA” software program [20]. The text provides radiocarbon age. Discussion of research results The morphological and physicochemical properties of sediments, the character of humus, and radiocarbon datings provide a means of reconstructing the evolution patterns of soils and landscape situations for the taiga-steppe ecotone, and the chronology of palaeogeographical events during the Holocene in the Baikal region. The Kuchelga section. The structure of the vertical profile of the section (Fig. 2) clearly shows six uneven-aged soils corresponding to soil formation stages of a different duration. The polygenetic profile consisting of buried soils V and IV records the Atlantic stage of soil formation (14С dates: 6125 ± 150 years ago, СОАН–7252; 4960 ± 80 years ago, СОАН–7117); buried soil III – the Subboreal stage (4270 ± 45 years ago, СОАН–6060; 3265 ± 80 years ago, СОАН–

326

L. V. Danko / Geography and Natural Resources 30 (2009) 324–331

Fig. 2. Structure of the Kuchelga section. Horizons: 1 – humus-accumulative sand-loamy, 2 – transitional sand-loamy, 3 – humus-accumulative coarse-silty sandy, 4 – sand-gruss. 5 – boundary of horizons, 6 – boundary of the effervescence zone. Carbonaceous neoformations: 7 – efflorescence (pseudo-mycelium), 8 – seepage mottles; 9 – blocks; 10 – crushed rock; 11 – gruss; 12 – calendar age, years. I–V – buried soils.

6439); buried soils II and I – the Early and Late Subatlantic (2400 ± 85 years ago, СОАН–6432; 370 ± 35 years ago, СОАН–6440), and the dayside soil marks contemporaneous soil formation. Judging from the radiocarbon age of the overlying soil V, the non-uniformity of the sediments that formed at the beginning of the Holocene indicates a multiple alternation of short-duration soil formation stages with stages of active accumulation of loose sediments. Fragments of peatified horizons are present in the lower part of the section. In the study

area, a cardinal change in landscape conditions occurred during the Early Holocene [21, 22]. The soil profile that was forming over the course of the Atlantic period is distinguished by the largest thickness of the humus-accumulative layer, a high degree of humusification, unstable structure and a conspicuous porosity, and by an abundance of calcareous neoformations. In all likelihood, the lower part of the profile that is represented by a brownish-black humus-accumulative (АVca) horizon began to form in the Early Atlantic beneath meadow-steppe communities

L. V. Danko / Geography and Natural Resources 30 (2009) 324–331

under conditions of a considerably higher heat availability and atmospheric humidification as against the present. The overlying brownish-dark-grey humus-accumulative horizon (А(АВ)IVca) corresponds to the Late Atlantic pedogenesis stage. Soils V/IV are characterized by the humate type of humus, elevated contents of coarse silt, a minimal rubbliness with heavily weathered fragments predominating, and, on the whole, by a high degree of reworking by soil processes (Table 1). The morphological and physicochemical differences between humus-accumulative horizons show that 5–6.2 thousand years ago the character of soil formation was gradually changing, and the rate of sedimentation was increasing. The small thickness of the А(АВ)IVca horizon can be accounted for by the partial removal of the Late-Atlantic soil due to an intensification of the denudation-accumulation processes at the interface of the Atlantic and Subboreal periods as a result of landscape-climatic changes. About 4.5 thousand years ago there occurred an extremum of a rather abrupt cooling which was recorded in different regions of Eurasia [23–25], including in the Baikal region [26]. It seems likely that this event manifested itself in the mountain-depression landscapes of the Baikal region as an enhancement of the seasonal contrast and continentality of climate. The subsequent pedogenesis stage resulted in the formation of the profile of subboreal soil III. The upper part of the profile clearly shows a humus-accumulative brownish-black horizon (АIIIca) which, when compared with the Atlantic and Subatlantic soils, is characterized by higher content of exchange bases, carbonates and organic matter. Humus is of the fulvate-humate type. Obviously, this soil was forming beneath steppe communities under conditions of adequate heat availability, yet with a decrease in moisture content. Soil III is overlaid with a layer of coarse-debris weaklyweathered gruss-sand filling material. This gives evidence of the active slope processes in the time interval from 3.3 to 2.5

327

thousand years ago and corresponds to the long-lasting stage of decreases in temperatures and atmospheric precipitation as recorded in the south and north of Siberia [25] as well as of an aridization of landscapes in the intermontane depressions of Southern Siberia [27]. The new dayside surface developed soil II under conditions of stabilization of the denudation-accumulation processes. According to diagnostic attributes, this soil was similar to contemporaneous organic-accumulative grey-humic soils. The differences involve the lower content of exchange calcium, silicon oxide, and sesquioxides. The humus content can also be compared with the present, because the reserves of organic matter in the case of burial of soils are usually decreasing with time on account of mineralization of humus and of the cessation of the entry of vegetable organic matter [17]. It can be suggested that soil II was evolving under conditions of a relative increase in heat and, most importantly, moisture availability as against the preceding period of time. Burial of the subboreal soil, however, records an intensification of the deluvial-gravitational removal associated, we believe, with a next long-lasting cooling. The main diagnostic attributes of soil I are similar to those of contemporaneous light-humic soils of the organicaccumulative type. The morphological characteristics, the low content of organic matter, and the fulvate type of humus indicate relatively cold climatic conditions at the end of the Subatlantic. The intensification of the exogenous processes that was responsible for the burial of soil I can be thought of as resulting from a maximal cooling during the Little Ice Age 200–250 years ago [24]. On the whole, the set of diagnostic attributes of the buried soil horizons makes it possible to compare soils IV/V and III with contemporaneous humus-accumulative soils of the chernozem type characteristic for the zonal steppes of southern Siberia, and soils II and I with organic-accumulative soils of contemporaneous geosystems in the study area. Table 1

Characteristic of buried soils and sediments of the Kuchelga section Age, 14С years The present 370 ± 35 2400 ± 85

Horizon

Water рН

С tot., %

Сha/Сfa

СО2 of carbonates, %

Ad АВ/С АIса АВIса/Сса

8.2 8.2 8.2 8.4 8.3 8.3 8.4 8.4 8.4 8.2 8.2 8.3 8.2 8.2

4.8 1.5 2.0 1.3 2.5 2.0 1.8 1.1 1.2 4.1 4.3 2.3 3.2 3.0

0.7 0.3 0.4 0.3 0.9 0.4 0.3 0.2 0.6 1.4 1.4 0.4 2.1 2.1

3.2 4.5 4.8 5.0 4.9 4.9 4.8 5.2 5.4 5.3 5.3 5.7 5.1 4.3

АIIса АВIIса

Late Holocene 3265 ± 80 4270 ± 45 Mid-Holocene 4960 ± 80 6125 ± 150

ВСIIса АIIIса ВСIIIса АIVса АVса

Exchange cations, mg/100 g Са2+ 35.6 24.0 26.4 20.0 25.2 25.6 20.4 16.0 25.2 37.6 35.6 25.2 29.2 28.8

Ca2+ + Mg2+ 37.6 26.0 28.8 22.8 28.8 28.8 25.2 20.0 30.0 42.8 41.2 30.0 33.6 34.0

328

L. V. Danko / Geography and Natural Resources 30 (2009) 324–331

The development of a differentiated soil profile indicates a long-lasting predominance of syngenetic processes of soil formation and weathering as well as a substantial attenuation of sedimentation processes. This is possible only under conditions of stabilization of the relief and with the landscape situation which is notable for high heat and moisture availability. According to palaeoclimatic reconstructions for the northern hemisphere [23–25], the formation time of soil V/IV and soil III corresponds to long-lasting maximal warmings during the Holocene, and that of soils II and I corresponds to shorter-duration warmings against the background of a general cooling trend in the Late Holocene. Furthermore, the amount of atmospheric precipitation was largely increasing during the aforementioned time intervals. Natural burial of soils bears witness to the disastrous development of the slope processes. The rate at which debris material outcrops on the surface was increasing during the time period concerned to an extent that the soil processes had not manage to rework it. The time limits of four such scenes were recorded in the Kuchelga section: 5–4.3 thousand years ago, after 3.3 and 2.4 thousand years ago, and 300–100 years ago which correspond to global coolings.

The Kharga section. The section exposed a polygenetic soil profile (Fig. 3) whose chronological correlation was carried out using two radiocarbon dates: organic remains (7200 ±140 years ago, СОАН–5776) buried in the subvertical seismogravitational crack, and a buried humus-accumulative horizon (1275 ± 70 years ago, СОАН–6441). The lower part of the profile is represented by sand sediments with traces of gleying, by weakly humusified sands with the inclusion of unrounded gruss and rubble, and by silty sand sediments. It is likely that the middle part of the section was shaping itself during the Atlantic period (from 7.2 thousand years ago) characterized by the following features: gradual transitions between horizons, absence of tonguing, brown color with bleaching in the upper part and with reddish hue in the lower part of the layer, compact composition, relatively strong nutty-finely prismatic (В2tca hor) and prismatic (В3tca hor) structure with luster on the edges of the soil separates, and good aggregation. The vertical distribution of silicon oxide, sesquioxides, calcium carbonates and fine dispersed particles is indicative of the occurrence of eluvial-illuvial processes (Table 2).

Fig. 3. Structure of the Kharga section. Horizons: 1 – humus-accumulative sand-loamy, 2 – eluvial sandy, 3–4 – textural light-loamy. 5 – boundary of horizons, 6 – boundary of the effervescence zone; 7 – gruss; 8 – crushed rock; 9 – seismo-gravitational crack; 10 – calendar age, years.

Early Holocene

7200 ± 140

Late Holocene

1275 ± 70

The present

Early Holocene

7485 ± 85

Mid-Holocene

5625 ± 80

4120 ± 95

8.7

74–95 8.6

8.5

46–73

96–120

7.1

31–45

6.2

12–19

6.6

6.3

2–9

25–30

8.5

101–110

6.2

8.4

96–100

20–23

8.1

8.0

71–90

91–95

7.8

7.6

51–54

60–70

7.5

41–50

7.7

7.4

31–40

55–59

7.3

21–30

7.2

16–20

Late Holocene

7.1

11–15

1840 ± 100

6.9

4–10

The present

Depth, cm

Water рН

0.5

0.1

0.1

0.4

0.6

1.0

1.8

2.4

1.2

1.5

1.8

1.5

2.3

2.0

1.8

2.8

3.7

2.4

3.2

2.8

2.7

С tot., %

–

0.4

0.4

0.5

1.0

1.4

1.4

1.7

1.9

1.8

1.4

2.4

2.1

1.2

1.0

0.9

0.8

Сha/Сfa

5.3

1.6

1.7

0.3

0.5

0.4

0.4

0.5

0.5

0.6

0.6

0.7

0.8

0.8

0.9

0.9

0.9

0.7

0.8

0.7

0.6

СО2 of carbonates, %

16.0

13.2

12.8

8.6

8.8

13.6

13.6

12.8

13.2

17.4

17.4

19.2

19.6

19.6

21.6

22.8

24.4

21.2

19.6

19.6

19.6

Са 2+

26.8

23.2

19.2

14.0

14.0

18.4

18.4

17.2

16.4

20.0

20.0

22.0

22.6

22.6

25.4

28.5

29.2

24.2

22.8

24.0

24.0

Са2+ + Mg2+

Exchange cations, mg/100 g

47.3

58.9

60.8

61.6

63.2

62.4

63.8

56.8

50.8

–

55.1

51.8

SiO2, %

4.9

6.5

5.8

6.1

4.5

4.6

4.4

4.3

4.8

–

4.2

4.8

Fe2O3. %

3.5

4.0

4.4

4.2

4.4

4.7

5.0

4.0

3.4

–

3.8

2.6

2.8

3.1

3.0

3.5

3.5

3.7

3.1

2.5

–

2.9

2.7

R2O

Al2O3 3.5

SiO2

SiO2

2.7

2.3

2.4

2.4

3.0

2.9

2.9

3.3

3.1

–

3.5

3.0

Fe2O3

Al2O3

0.5

0.2

0.3

0.3

0.4

0.4

0.4

1.0

0.7

–

1.3

0.7

Fe2O3

FeO3

Note. “–“ – undetermined, the geochemical coefficients are calculated from silicate analysis data: ВА – basic (СаО + К2О + Na2O/Al2O3), Cc – carbonate (СаО/MgO).

Kharga

Kulura

Section

Age, 14 С years from 1950

Characteristic of buried soils and sediments

1.1

0.5

0.6

0.5

0.5

0.5

0.5

0.7

0.7

–

0.7

0.6

ВА

2.7

1.6

1.4

1.0

1.4

1.4

1.3

5.9

5.8

–

5.4

6.1

Cc

Table 2

L. V. Danko / Geography and Natural Resources 30 (2009) 324–331 329

330

L. V. Danko / Geography and Natural Resources 30 (2009) 324–331

Therefore, the soil can be classified with texture-differentiated soils with a profile of the А–(EL)Вt–ВС type. The occurrence of a seismogravitational crack in this layer records one of the recent events of an active geodynamical situation that set in 9.1–8.3 thousand years ago [28]. The buried humus-accumulative horizon, identified in the upper part of the section, reflects the characteristic properties of Subatlantic soil formation (1.2 thousand years ago) and, according to diagnostic attributes, bears similarities with contemporary organic-accumulative grey-humus soils. An interruption in soil formation as recorded by the overlying layer of rubble sediments is indicative of the activity of the deluvial removal at the end of the Subatlantic. Kulura section 1–03. The vertical profile of the section is represented by a weakly differentiated polygenetic humusaccumulative thick (1 m) layer which had been forming in the interval 9000–1000 calendar years ago and is characterized by a low degree of aggregation, a loamy-sand grain-size distribution, and by a high content of gruss-debris material. Note that in the foothills area of the Primorsky Range and on the Priolkhonskoye plateau, such polygenetic soils typically occur in the zone of faults. The properties of sediments in the lower part of the section (see Table 2) occurring beneath the layer with radiocarbon dating of 7485 ± 85 years ago (СОАН–6433) imply the formation (at the end of the Early Holocene) of a thin layer of humus-accumulative soil with humate-fulvate humus, the composition of which was dominated by calcium-bound humic acids. Based on the fact that relict humus of soils is mineralized faster in drained areas and on lighter-weight earth materials and that in weakly drained areas and heavy earth materials its content had remained almost unaltered within as long as 3–4 thousand years [17], we are led to suggest that the soil under investigation has a rather high initial humusification. According to the aggregate of diagnostic attributes, the overlying humus-accumulative layer is clearly divided into two horizons which, judging by the datings, can be referred to the Early (7485 ± 85 years ago, СОАН–6433) and late Atlantic (5625 ± 80 years ago, СОАН–6434) period of time. There is a conspicuous layer in between, showing a clear increase in the content of unrounded gruss-debris material, which indicates an intensification of the slope processes, perhaps, as a result of a short-lasting cooling and a decrease in atmospheric precipitation. The Late Atlantic horizon is notable for an elevated content of organic matter and exchange calcium, and for a rather high level of humic acids. Such characteristic features suggest the more intense development of soil formation processes, notably the humus formation processes. The increase of the amount of debris material in the layer overlying this horizon can be thought of as resulting from an enhancement of the deluvial removal during a cooling at the interface of the Atlantic and the Subboreal time. The principal attributes of the humus-accumulative layer that has shaped itself in the Subboreal (4120 ± 95 years ago, СОАН-6435), are signaled by maximum humus accumula-

tion. It is distinguished by darker (black) color and a high (up to 6%) reconstructed content of humus, and by the predominance of humic acids in its composition, which are bound to calcium, which implies an abundant entry of remains of grass vegetation into the soil under dry, sufficiently warm conditions. On the whole, this layer compares in its attributes with contemporary chernozems. The specific character of Subatlantic soil formation is embodied in the layer dated 1840 ± 100 years ago (СОАН– 6436). It is similar in its properties to the contemporaneous organic-accumulative grey-humic soils. The difference implies lower levels of humus and exchange calcium. Conclusion The analysis of the reconstructed chronology of soil formation in the study area indicates a contrasting evolution of soils during the Holocene under the influence of long-lasting changes in landscape-climatic conditions. The stratigraphic sequence of Quaternary sediments and palaeosoils in the sections furnish a means of identifying for the Baikal region several soil formation stages of a different duration, each of which was distinguished by intrinsic characteristics of the soil genesis. The longest stage of intense soil formation dates back to the latter half of the Atlantic period (7–5 thousand years ago). At the Subboreal and Subatlantic periods the pedogenesis stages had a shorter duration. The soil formation stages alternated with stages of intensification of denudation-accumulation processes in connection with global changes of climate. On the whole, the Holocene was quite a complicated epoch, and the soil cover of the taiga-steppe ecotone along the western shores of Baikal had gone in its evolution through a number of stages characteristic for all soils of the Baikal region. First and foremost it is the stage of Early-Holocene shaping of the soil cover with a discontinuous pedogenesis (an alternation of soil formation stages with stages of intensification of denudation-accumulation and permafrost processes), and with formation of thin layers of soils of the humus-accumulation type during the boreal period. A next stage involves Mid-Holocene soil formation characterized by the stablest state of soil cover, and by the shaping of fully developed soils with a texture-differentiated profiles in the foothills area of the Primorsky Range and of accumulative-humus soils of the chernozem type on the slopes of the Kuchelga-Talovskaya depression. Humus accumulation, carbonization and lessivage were prevalent in the soil formation processes. The last stage comprises Late Holocene soil formation, over the course of which the soils in the study area were evolving in the wake of a change in bioclimatic conditions. The Subboreal period was the development optimum of steppe soil formation under the driest climate. A cooling, coupled with an increase in atmospheric precipitation, at the interface of the Subboreal and the Subatlantic was accompa-

L. V. Danko / Geography and Natural Resources 30 (2009) 324–331

nied by a change of the soil formation type, an attenuation of the humus formation and humus accumulation processes, and by an intensification of erosion and cryogenic processes. The contemporary features of soil formation began to shape themselves during the Subatlantic period. Soil evolution is an important component of the development of geosystems. The study of the palaeosoils in the Baikal region is basic to an indication of palaeogeographical events and phenomena, palaeoclimatic and palaeolandscape reconstructions, and eventually to an understanding of the evolutionary-dynamical organization patterns of the region’s geosystems and forecasting their development under differrent-scale changes of climate and under anthropogenic impacts.

12.

13.

14. 15. 16.

References

17.

1. Bezrukova E. V. Palaeogeography of the Baikal Region During the Late Glacial and Holocene. Novosibirsk: Nauka, 1999, 128 p. 2. Karabanov E. B., Prokopenko A. A., Williams D. F. et al. A new record of Holocene climate change from the bottom sediments of Lake Baikal. Palaeogeography, Palaeoclimatology, Palaeoecology, 2000, v. 156(3–4), pp. 211–224. 3. Demske D., Heumann G., Granoszewski W. et al. Late glacial and Holocene vegetation and regional climate variability evidenced in high-resolution pollen records from Lake Baikal. Global and Planetary Change, 2005, v. 46, 255–279. 4. Vorobyeva G. A., Goryunova O. I. and Saveliev N. A. Chronology and palaeogeography of the Holocene of southern Middle Siberia. In: Geochronology and the Quaternary Period. Moscow: Nauka, 1992, pp. 174–181. 5. Vorobyeva G. A. and Goryunova O. I. The Early – Mid-Holocene of the Preolkhon region in light of the latest data. In: The Problems in Archaeology, Ethnography and Anthropology of Siberia and Neighboring Territories. Novosibirsk: Institute of Archaeology and Ethnography SB RAS Publisher, 1997, v. 3, pp. 179–183. 6. Vorobyeva G. A. and Mats V. D. The evolution of soil formation and subaerial sedimentation in the Baikal-Yenisei Siberia. In: Soil as a Link of Functioning of Natural and Anthropogenically Transformed Ecosystems: Proc. II Intern. Scint.-Pract. Conf. Irkutsk: Irkutsk University Publisher, 2006, pp. 18–24. 7. Shantser E. V. Studies on the Theory of Genetic Types of Continental Formations. Moscow: Nauka, 1966, 233 p. 8. Targulyan V. O. The memory of soils: formation, carriers, spatial diversity. In: The Memory of Soils: The Soil as the Memory of Biosphere-Geosphere-Anthroposphere Interactions. Moscow: Izd-vo LKI, 2008, pp. 24–57. 9. Atlas of Baikal. Moscow: FSGKR, 1993, 160 p. 10. Danko L. V., Kuzmin S. B. and Snytko V. A. Risk assessment and disaster management for natural and anthropogenically induced geologic hazards: Application for Preolkhon region, Western Lake Baikal, Siberia, Russia. Natural Resources Research, 2000, v. 9, No. 4, pp. 1–5. 11. Kuzmin S. B., Danko L. V., Andreyeva I. O., and Bezrukova E. V. The stages of anthropogenic impact on landscape in the Pre-

18.

19. 20.

21.

22.

23.

24.

25.

26.

27.

28.

331

olkhon region (Western Baikal region). Izv. RAN. Ser. geogr., 2006, No. 1, pp. 47–60. Danko L. V., Bezrukova E. V. and Kuzmin S. B. Regional and local development patterns of present-day geosystems in the Baikal Region. Landscape Analysis for Sustainable Development: Theory and Applications of Landscape Science in Russia. Moscow: Alex Publishers, 2007, pp. 137–143. A Classification and Diagnostics of Soils. Shishov L. L., Tonkonogov V. D., Lebedeva I. I., and Gerasimova M. I. Smolensk: Oikumena, 2004, 342 p. Ivanov I. V. and Alexandrovsky A. L. The methods of studying the soil evolution. Pochvovedeniye, 1987, No. 1, pp. 112–121. Ivanov I. V. Soil Evolution of the Steppe Zone in the Holocene. Moscow: Nauka, 1992, 144 p. Dergacheva M. I. Archaeological Pedology. Novosibirsk: Izdvo SO RAN, 1997, 228 p. Alexandrovsky A. L. and Alexandrovsky E. I. Soil Evolution and Geographical Environment. Moscow: Nauka, 2005, 223 p. Soil Chemistry. A. Basic Elements. Second revised edition. Ed. A. H. Bolt and M. A. M. Bruggenwert. Elsevier Science Publishing Company, 1978, 281 p. Orlov D. S. Soil Chemistry. Moscow: Izd-vo Mosk. un-ta, 1992, 400 p. Danzeglocke U., Bernhard W. and Jöris O. CalPal-University of Cologne Radiocarbon Calibration Program Packagе. http:// www.calpal-online.de/index.html. ver. 1.5. Vorobyeva G. A., Goryunova O. I. and Novikov A. G. Culturalchronological periodization and the palaeoecological situation of the Early Holocene in the Preolkhon region. In: Current Problems in Archaeology of Russia. Institute of Archaeology and Ethnography SB RAS Publisher, 2006, pp. 189–191. Danko L. V. On the development tendency of geosystems along Baikal’s western shores. Geografiya i prirod. resursy, 2005, No. 4, pp. 48–54. Klimanov V. A. Cyclicity and quasi-periodicity of climatic fluctuations during the Holocene. In: Palaeoclimates During the Late Glacial and Holocene. Moscow: Nauka, 1989, pp. 29–33. Velichko A. A., Andreev A. A. and Klimanov V. A. Climate and vegetation dynamics in the tundra and forest zone during the Late Glacial and Holocene. Quaternary International, 1997, Nos. 41/42, pp. Velichko A. A., Klimanov V. A. and Kononov Yu. M. Climate change over the last millennium versus climatic variations during the Holocene. In: Possibilities of Avoiding Climate Change and Its Negative Consequences: The Problem of the Kyoto Protocol. Moscow: Nauka, 2006, pp. 306–340. Bezrukova E. V., Belov A. V., Abzayeva A. A. et al. First detailed dated records of vegetation and climate changes in the Northern Baikal region during the Mid-Late Holocene. DAN, 2006, v. 411, No. 2, pp. 254–258. Dirksen V. G. and van Geel B. Mid to Late Holocene climate changes and its influence on cultural development in South Central Siberia. In: Impact of the Environment of Human Migration in Eurasia. Dordrecht; Boston; London: Kluwer Academic Publishers, 2004, pp. 291–307. Kuzmin S. B., Mekhanoshin P. A. and Danko L. V. New data on geodynamical situations during the Late Glacial and Holocene in the Baikal region. Izv. RGO, 2007, issue 3, pp. 45–52.