Conflagration fires in taiga landscapes of Central Siberia

We examine the issues relating to the origin of conflagration fires, and the conditions for their emergence and occurrence in taiga landscapes of Central Siberia. We carry out an analysis of the natural-pyrological conditions of landscape where conflagration fires occur.     

Resoiling on anthropogenically disturbed surfaces in the southern taiga subzone

Based on investigating dated anthropogenic structures, we present the results derived from studying the development features of soddy podzolic soils over the course of the first 600 years from the zero time of soil formation. A commonness of the chronological regularities has been ascertained for the reproduction of morphological structure of soddy podzolic and chernozemic soils.     

Using the landscape map to assess the productivity of geosystems in the southern taiga of Western Siberia

The principle of structural-dynamical landscape science was used in mapping the taiga of the Ob’-Irtysh, Lower Irtysh and Tobol regions. The spatiotemporal dynamics of the regions’ geosystems is outlined, and their productivity is assessed from forest inventory data and NDVI indices as calculated on the basis of Landsat-5 TM images.     

Diatom Paleolimnological Record of Holocene Climatic and Environmental Change in the Altai Mountains, Siberia

The sedimentary diatom records of three shallow lakes in the Altai Mountains, southern Siberia, were examined to assess the nature and timing of Holocene environmental changes. Few paleoenvironmental records, especially reconstructions not based on pollen, have been reported from this region. The lakes differ in elevation, annual precipitation, and catchment vegetation. Diatom assemblages in all lakes were dominated for the entire period of record by small benthic species of Pseudostaurosira Williams & Round, Staurosira Ehrenberg, and Staurosirella Williams & Round. Planktonic taxa only occur in very low abundances (<5%). The most diverse diatom flora was found in Dzhangyskol, which is situated at the lowest elevation within a forested catchment. A lack of detailed information on the ecological preferences of the dominant taxa and the complexity of environmental drivers make direct interpretation of the diatom record difficult. However, other proxies suggest that dramatic shifts in dominance between Staurosira elliptica and Staurosirella pinnata in Grusha Ozero reflect millennial-scale variability in climate. Together, chironomids and diatoms provide evidence of a cooling possibly correlative to the Younger Dryas Stade and subsequent early-Holocene warming consistent with pollen evidence of afforestation, which also is likely linked to increased humidity. By ~6000 cal year BP, the transition to a cooler, more continental climate had begun. The diatom record of Akkol shows significantly less variation in diatom community composition, but biogenic silica accumulation rates, a proxy for diatom productivity, appear to reflect climatic variability driven by insolation trends over the past 8000 years. Long-term variability in Dzhangyskol is not clearly linked to climate.     

The ecologo-geographical framework for the protection and recovery of taiga reindeer populations within the Konda river basin (Western Siberia)

The key aspects of reindeer ecology within the Konda river basin are considered. The study revealed the factors governing the characteristics of calving reindeer pastures determined by the structure of forest-bog landscapes of a different generalization level. A deficit of such pastures is regarded as the factor of differentiation of reindeer groups with respect to migrants and residents. It is shown that the individual geocomplexes have a multifunctional role. Of particular significance among them are the aufeis glades with outcrops of salt-saturated groundwater, and the dark-coniferous forests along river valleys rich in epiphytic lichens (beard lichens).     

阿尔泰山中东部西伯利亚落叶松生长量及其对气候变化的响应研究

利用阿尔泰山中东部两个样点(AYS、SYK)的西伯利亚落叶松(Larix sibirica)树轮资料,采用新疆西伯利亚落叶松一元材积式获得1969-2011年材积生长量序列。利用相关分析和回归分析等方法对生长量数据和气象资料进行分析,研究气温要素与生长量的关系及树木生长对气温和降水变化的响应。结果表明:近50 a来,西伯利亚落叶松材积生长量表现出显著增加趋势,且与生长季气温有较好的相关性;与当年6月降水量呈负相关趋势,8月降水量呈正相关趋势;生长季平均气温在19~20.9℃时,西伯利亚落叶松生长量最大;SYK样点西伯利亚落叶松生长对气温变化的敏感性高,气温每升高1℃生长量增加0.936 mm³·棵^-1;AYS样点西伯利亚落叶松生长对气温变化的敏感性较低,气温每升高1℃生长量增加0.661 mm³·棵^-1。     

Transformation of climatic response in radial increment of trees depending on topoecological conditions of their occurrence

We report the research results derived from identifying the regional climatic signal contained in the coniferous tree ring-width variability for different topoecological conditions in the forest-steppe of the Republic of Khakassia. It is found that under different growth conditions for trees of the same species the climatic signal undergoes a significant transformation. We demonstrate the possibility of using a combination of tree-ring chronologies of different tree species for an adequate dendroclimatic reconstruction of the leading climatic variables.     

Combining ordination techniques and geostatistics to determine the patterns of diatom distributions at Lake Lama, Central Siberia

The patterns of spatial variation of diatom assemblages from surface sediments in Lake Lama were quantified using a combined approach of ordination and geostatistics. The aims were (i) to estimate the amount of variation between diatom assemblages within the lake, (ii) to model the spatial variability of the diatom assemblages and their diversity, and (iii) to map the diatom distributions in the lake. A correspondence analysis (CA) separated the diatom assemblages into a planktonic and a periphytic group. Rheophilic taxa were found within the periphytic group. Variogram analysis showed that only the sample scores of the first CA axis and the Shannon diversity index were spatially structured. The range of spatial correlation was estimated to be 55 km for both variables. The diversity and, to a lesser extent, the sample scores had considerable small-scale variability of about 20 and 3%, respectively. Estimates of the first component of the CA and the Shannon index were derived using block-kriging. The maps of the estimates provided a basis for partitioning Lake Lama according to the spatial structures into an eastern and a western basin, a north–south connection between the basins, and a north–south directed tip at the far eastern end. It was shown that variation in diatom assemblages is mainly spatially structured at the catchment scale and that there is a considerable amount of variation at smaller scales. According to the modeled spatial distribution, the assemblages are most likely affected by the lake size, morphology, and the water and nutrient input introduced by rivers. This has to be taken into account when paleolimnological interpretations are drawn from records of complex lake systems like Lake Lama.     

Structure and functioning of soil zoocenoses of taiga geosystems of the Lena-Angara plateau

A unified methodological approach was used to study the soil zoocenoses of uneven-age industrial areas of the Kovykta gas and condensate field. Regeneration of the soil-biotic block is characterized by sequential changes in quantitative characteristics, and in the taxonomic and functional structure of invertebrate communities. The study revealed distinguishing characteristics of the progressive successions of drastically disturbed mountain-taiga geosystems, and the factors that are responsible for the direction and duration of the individual successions.     

The economic-geographical position of Siberia in Russia and in the world

Three main kinds of economic-geographical position (EGP) of Siberia: global, international transit and neighboring, and interstate, are considered. A quantitative assessment is made of the macroregion’s global position relative to world markets. The study ascertained the role played by the EGP in the formation of economic-settlement patterns of Siberia. The possible avenues for more intense use of this position are suggested.     

Seismic investigation of the El’gygytgyn impact crater lake (Central Chukotka,NE Siberia): preliminary results

The 12 km wide and about 175 m deep El’gygytgyn crater lake in Central Chukotka, NE Siberia, is of special interest for investigation as it could provide the first undisturbed 3.6 Ma terrestrial record from the Arctic realm, reaching back a million years before the first major glaciation of the Northern Hemisphere. A single-channel seismic survey was carried out on an expedition to the lake in 2000, in which both high resolution and deep penetration data were acquired. Seismic data suggest an impact crater structure in Cretaceous volcanic bedrock, indicated by velocities of >5000 m s⁻¹, whose upper 500–600 m is brecciated. The lake is filled with two units of sediments, the upper one well stratified and the lower one massive. In the center of the lake, the combined thickness of the two sedimentary units is estimated to be 320–350 m. The upper unit is draped over the location of an interpreted central peak and is locally intercalated with debris flows, mainly in the western part of the lake and at the lake margins. Most of the lower unit is obscured by multiples as a result of high reflection coefficients in the upper unit. As at least the upper unit appears to be undisturbed by glaciation, the lake should yields unique information on the paleoclimatic development of the East Siberian Arctic. This is the fourth in a series of eleven papers published in this special issue dedicated to initial studies of El'gygytgyn Crater Lake and its catchment in NE Russia. Julie Brigham-Grette, Martin Melles, Pavel Minyuk were guest editors of this special issue.     

季节变化对全球气候变化的响应——以湖北省为例

根据湖北省10个代表站1951(或建站)~2006年逐日平均气温,计算分析了四季初日和长度及其变化趋势,以揭示气候季节对全球气候变暖的响应。结果表明:(1)湖北省平均春、夏、秋、冬四季初日分别为3月22日、5月27日、9月27日、11月27日,四季长度分别为65.7、122.8、60.9、115.6d,且时空差异明显;(2)56a来湖北省平均入春、入夏分别提前2.8、1.6d,入秋、入冬分别推后4.0、6.1d;(3)56a来湖北省平均冬季缩短8.9d,夏季延长6.3d,秋季延长2.0d,春季无变化;荆州夏季延长21.1d,武汉冬季缩短17.0d。     

Geographical determinants of the quality of life in Siberia

Central to socio-geographical research is the principle of determinism which provides a means for analyzing the development patterns of social systems in the context of their geographical location and natural and territorial factors that are responsible for the geographical heterogeneity of social phenomena and processes reflecting the quality of human life.     

The resource-ecological basis of the forest complex in East Siberia

The resource-ecological potential of forests is represented by the reserves of growing stock and total phytomass. Non-exhaustion forest exploitation can be based on a balance of deafforestation and appropriate regeneration of timber and other forest resources, and efficient protection against fires and other negative impacts for a stable development of the forest complex and for sustained resource and ecological functions of forests.     

邕江洪水的特征及其气候成因研究

利用邕江洪峰水位、年最高水位资料及邕江流域气象测站逐月降雨量资料,对邕江洪水的特征进行分析表明,洪水多数发生在华南后汛期7～9月,并与流域夏季降雨量密切相关。利用NCEP/NCAR再分析资料以及NOAA卫星观测的OLR资料,分析邕江洪水形成的天气气候条件,研究结果表明:热带气旋影响是邕江发生洪水的主要原因。当西太平洋副热带高压位置偏北,邕江流域易受热带辐合带(ITCZ)影响,对流活跃,热带气旋活动频繁,此时邕江易发生洪水;地形对邕江洪水的形成有较重要的作用;邕江洪水易发生在赤道东太平洋海温为负距平的条件下。分析了邕江洪水气候成因。     

Spatial Structure of the Relationships of Annual Precipitation Amounts in Siberia and Kazakhstan

Joint variability in annual precipitation amounts across the territory of Siberia and Kazakhstan was analyzed using multifactor stochastic modeling tools. It is shown that there are statistically significant correlations between these variables, which satisfy the temporal stability condition. Such correlations that reflect the regularities in the formation of the annual precipitation field have also both a positive and a negative character. Positive correlations are observed between closely spaced meteostations and reflect mainly the local homogeneity of the formation of the annual precipitation field. They are reliably identified by methods of both multifactor and single-factor statistics. Negative correlations are observed between the significantly more remote weather stations. They are revealed according to the condition of the significance of the deviation from zero for the negative coefficients of the variables in multifactor linear regression models. Paired negative, statistically significant associations between annual precipitation amounts at meteostations occur extremely rarely. From an applied perspective, the presence of significant regular correlations between annual precipitation amounts can be used to construct models based on such regularities, for an approximate reconstruction of missing data in the past or in problems of a combined forecasting of the expected annual precipitation for the territory under consideration in the future.     

厦门市旅游气候资源评价及其利用

本文在评价了福建沿海城市厦门的气候特点和优势后，指出厦门风光秀丽，常年无冬，秋春相连，夏无酷暑，气候宜人，四季咸宜旅游，有利于形成独具特色的自然景观及形成地方特色的农渔产品，为旅游业的发展提供了丰富的物质基础；并提出利用厦门旅游气候资源，培育经济增长点，使资源优势转变为经济优势的开发对策。     

Climatic and Anthropogenic Influences on Radial Growth of Scots Pine at Hanvedsmossen, a Raised Peat Bog, in South Central Sweden

Past studies of the climatic influence on tree growth at peat bogs in northern latitudes have shown weak correlation between annual tree-ring widths and climatic parameters during the growing season. At Hanvedsmossen, a raised peat bog in south central Sweden, tree-ring width chronologies from one drained and one undrained growth site, as well as one dry site outside the bog, were compared to meteorological records. Low temperatures, which means less evaporation, as well as high precipitation appear to be inhibiting pine growth at the undisturbed bog site as the trees are sensitive to changes in the local water table. Drainage causes an instant increase in annual tree growth for approximately 10 years. If draining is maintained, the response to climate of the pines resembles that of pines growing on mineral soils. The variance in annual tree-ring growth explained by temperature/precipitation or both was low for the entire lengths of all chronologies, but high for some analysed subperiods; the significant months changed with time. The reason for this seems to be that pines at Hanvedsmossen are growing in a region where precipitation and temperature are less limiting to tree growth than at higher and lower latitudes.     

Climatic Changes from 12,000 to 4,000 Years Ago in the Austrian Central Alps Tracked by Sedimentological and Biological Proxies of a Lake Sediment Core

Major and trace elements, minerals, and grain-size were analysed from the early to mid-Holocene (12 to 4 ky BP) period of a sediment core from the Alpine lake Oberer Landschitzsee (ObLAN, 2076 m a.s.l.), which is located on predominantly crystalline bedrock on the southern slopes of the Austrian Central Alps. Geochemistry and mineralogy were compared with diatom-inferred (Di-) ‘date of autumn mixing’ (A_mix), DOC, pH, and selected indicator pollen species from the same sediment core. Principal components analysis (PCA) indicated a positive correlation between processes triggered by temperature and precipitation (e.g., lake mixing, DOC). PCA grouped indicators of physical weathering and enhanced catchment run-off (sand, quartz, feldspar), elements of weathering (e.g., Ti, Rb, Mn) under dryer conditions (clay to silt fractions), and elements that probably were related to changes in redox conditions (Cu, Fe, S, Zn). The duration and height of the snow-pack played an important role in this high-alpine environment, affecting weathering, erosion, pH, and lake stratification. Low Alnus viridis pollen abundance, together with markers for increased elements of erosion, indicated extensive snow-pack. Changes in S coupled with As, and elements indicating increased weathering, reflected climate oscillations. LOI was affected by productivity and erosion. High (late) Di–A_mix coupled with increased Di-DOC indicated prolonged summers with increased productivity. Cold and wet (snow-rich) phases and subsequent melting caused low pH and a decoupling of the significant linear correlation between sedimentary Ca and Di-pH. Weathering and leaching during climate deteriorations opposed the long-term trend in a loss of cations and forced in-lake alkalinity generation during the following lake warming. Overall, the multi-proxy study indicated complex climate-driven processes within different time-scales (long-term trends, climate oscillations, seasonality). The climate oscillations within 12–5 ky BP corresponded well with the cool and wet phases known from central Europe suggesting a dominant common Atlantic climate impact. When Mediterranean climate established between 5 and 4 ky BP, its influence on the southern slopes of the Alps increased.     

The structure of denudation cycles in the forest-steppes of Middle Siberia

A comparison between the evidence from station-based investigations into contemporaneous denudation with the data on the structure of reference sections of the loess formation from the late Pleistocene revealed a hierarchical structure of denudation cycles in the submontane forest-steppes of Middle Siberia. It is established that an elementary 3–5-year cycle exhibits features typical of high-order cycles. Similarity features manifest themselves in the denudation mechanism, and in the sequence of phase change inside the cycles. A denudation cycle of any hierarchical level inheritedly from the late Pleistocene includes accumulation phases of Aeolian material, redistribution of matter by the slope processes, and of fluvial removal of matter from the system.