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1.
Basic patterns of contemporary functioning of the denudation systems are presented for the areas of southern Siberia. The denudation triggering mechanism is elucidated, which is associated with the climate-induced alternation of the zonal and extreme phases of denudation cycles. Three regional types of denudation with a different directedness of relief-formation, controlled by the structure of climatic fluctuations, are considered.  相似文献   

2.
We examine the contemporary denudation cycles in the steppes of Khakassia, including the phase of integration of matter in the system and of the nival-proluvial removal, and the deflation phase of long-range transport of matter from the Minusinskaya depression. The cartographic model for the contemporary functioning of denudation systems is presented.  相似文献   

3.
We consider some theoretical and methodological issues relating to stability assessment of natural development of vegetation in geosystems. We have ascertained the evolutionary-genetic essentials of vegetation stability and presented the cartographic states of its assessment. The stability map for plant communities has been developed on a conjugate scale of predictive-cartographic products.  相似文献   

4.
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.  相似文献   

5.
This study constitutes a comprehensive attempt to interpret the multistoreyed benchland scenery of the South Indian shield. In South India, two rifted margins (and now competing base levels), a low-elevation margin facing the Bay of Bengal, in existence since ≈130  Ma, and a younger (65  Ma) high-elevation margin facing the Arabian Sea, together with a high-standing backbone of extremely resistant granulitic rocks known as charnockites, have influenced the long-term erosional response to rock uplift and to the eustatic shift of shorelines in a complex way.
Several tiers of flat-lying, denudational topographic surfaces, which are indifferent to stratification, schistosity or foliation and highlighted by a characteristic weathering mantle, are identified and the conditions of their genesis discussed. General definitions and assumptions concerning the evolution of planation surfaces are presented. A major key issue is the nature of crustal uplift in cratonic regions: its relation to global tectonics, its role in the redistribution in time and space of available relief and in the deformation of pre-existing planation surfaces, and its bearing on denudational signals which may be recorded both by isotopic measurement techniques and offshore sedimentary sequences. The proposed denudation chronology considers all these aspects, and the analysis sets out to establish a thread of geodynamic events that can account for the observed morphology. Drainage, weathering and crustal uplift patterns, geological structures and chronostratigraphic data are examined in relation to their possible connections with the migration of drainage divides and surface lowering patterns. The high number of degrees of freedom involved when considering the long-term interplay between gravity-driven and radiation-driven denudation systems is one of the many problems facing this analysis, and is extensively addressed in the discussion.  相似文献   

6.
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.  相似文献   

7.
Using three key areas as an example we examine the tendencies toward changes of the mountain geosystems in southern Siberia caused by fluctuations of climate. Presented are the quantitative parameters of the dynamics of nival-glacial geosystems (glaciers, perennial snow clusters, icings, and stony glaciers). Portions of large-scale maps for the key areas generated for a subsequent monitoring of the mountain geosystems are presented.  相似文献   

8.
An analysis is made of the glaciation status of the mountains in the south of East Siberia to reveal a number of characteristics of changes in glacier systems. It is determined that the mountain systems are all experiencing a deglaciation caused by global climatic changes, while the rates of degradation have increased considerably since the late 1980s. It is established that over the last several decades the rate of thawing of glaciers has decelerated according to data for the key sites in the Kodar, Baikal’skii, Barguzin. Munku-Sardyk and Eastern-Sayan mountain ranges, which is associated with a decrease in mean annual air temperatures in 2009, 2010, 2012 and 2013 after the maximum values in 1990, 1994, 1995, 1997, 2002 and 2007. The changes recorded in the amount of solid atmospheric precipitation do not produce any definite trends in all of the mountain systems analyzed. It is determined that, given a relatively small snow accumulation, the glaciers are fed by snow avalanches and persist due to accumulation of large reserves of cold throughout long and cold winters which impede an intense ablation and promote the sustenance of glaciation. It is pointed out that the thawing of glaciers (especially cirque glaciers) involves a decrease in their thickness, whereas their area changes little.  相似文献   

9.
The evolution of estuarial geomorphological and sedimentary systems in the Late Holocene is considered using the river deltas along the Arctic coast of Siberia as an example. Presented are the stadial development patterns of the main morphogenetic types of estuarial systems for the period of stabilization of postglacial transgression of the World Ocean.  相似文献   

10.
An analysis is made of 100 years of development of specially protected natural territories of Siberia. Attention is centered on the characteristic features of territorial nature conservation which are determined by the dependence on the political, economic and managerial factors. The analysis revealed the periods of formation, decline, opposite trends and negative dynamics in the establishment of new protected natural territories. Using the history of reserve management and studies of Russia as an example, it is shown that most innovations were tested in Siberia, starting from the establishment of Russia’s first state zapovedniks and zakazniks and ending with the setting up of joint directorates of specially protected natural territories in recent years. It is pointed out that the approaches in substantiating the system of protected natural areas were characterized by fundamental differences: from the organization of “pristine benchmarks” of nature with the ideology of total non-interference, to “farm zapovedniks” for breeding valuable game animals and active maintenance of the population of rare species accompanied by measures to eliminate “harmful” species. The rivalry between the geographical and biocentric approaches is described: in the former case, the preservation of typical natural systems was dominant; in the latter case, the preservation of rare and endangered species was paramount. It is concluded that the unevenness of distribution of zapovedniks, zakazniks and national and natural parks depends on the degree of development and exploration of a relevant territory, the likelihood of a total disappearance of the most valuable areas, and on the existence of lands of indigenous ethnic groups. It is demonstrated that the process of development of the system of territorial nature conservation is governed by the administrative initiative, consideration for the characteristics of a region’s economic development and changeable institutional conditions as well as by the factors of the country’s foreign and internal policy.  相似文献   

11.
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.  相似文献   

12.
We examine the time coincidence and spatial homogeneity of the annual stream runoff fluctuations in Siberia and the Far East. A regionalization of the study territory for the time coincidence of the stream runoff fluctuations has been carried out by analyzing the correlation matrix on the basis of the algorithm of automatic classification of objects through identification of groups with homogeneous attributes according to a specified homogeneity criterion. The territory’s spatial homogeneity was assessed by constructing and analyzing spatial correlation functions and accompanied by a checking for the possible anisotropy.  相似文献   

13.
An analysis of statistical data has shown that most Russia’s cities with unfavorable ecological conditions refer to the Siberian Federal District. This is due to considerable amounts of atmospheric emissions from large industrial enterprises with imperfect equipment and technologies as well as to the unfavorable conditions of diffusion of dust and gas emissions. Attention is given to the role of nonferrous metallurgy, including aluminum smelting, in environmental impairment. It is shown that the pollutant emissions not only pollute the atmosphere, but also when returning to land surface, they alter the soil-geochemical habitat conditions for vegetation and animals and lower the quality of human life. The shifting of aluminum smelters to Siberia and the construction of major plants pose a threat of impairment in the ecological situation over a significant part of the territory, which is illustrated with the impact of pollutants from several aluminum smelters. Thus, in spite of the fact that the aluminum smelters of Khakassia are provided with up-to-date equipment, their 30-year-long operation has led to formation of a technogenic geochemical anomaly with an area of about 80 km2, containing 0.05 to 0.2% of the total amount of fluorine in the 0–15 cm topsoil, and water-soluble fluorine from 1 (10 mg/kg) to 3 MAC. The investigations show that the Soderberg method when used to obtain aluminum in large amounts (0.8–1 mln. t per year) is not as ecologically safe as advertised. It is therefore necessary to perfect the technologies used or to decrease the amount of aluminum produced.  相似文献   

14.
The mean values of potential soil loss and of sediments that are removed from the gullies are calculated, and the data on the rates of erosion-accumulative processes on arable lands, in gully-dried-up river-bed systems are provided. For the Yelovka and Kuitunka rivers the basin component of the erosion-accumulative processes has been assessed qualitatively. The sequences of erosion loss to drainage basins of small rivers as well as of scouring and accumulation are determined.  相似文献   

15.
Fuks LP 《Soviet geography》1987,28(10):756-776
"[This] paper devoted to the settlement system and the problem of rural population loss in that portion of West Siberia having a significant agricultural base takes issue with some implicit assumptions incorporated within the General Scheme of Settlement within the USSR. More specifically, policies calling for the deliberate, i.e., forced, resettlement of rural population in selected villages in order to provide economies of scale in rural services provision are criticized on two major counts: (1) that such 'enlarged' settlements will still be too small to be allocated the necessary range of functions according to standard city-planning formulae, and (2) that they accelerate rural depopulation by serving as spring-boards for migration to still larger centers."  相似文献   

16.
The role of the Ob-Irtysh valley in the dynamics and evolution of the soil-earth materials factor of taiga-plain landscape is considered. The study demonstrates the mechanisms of operation of the soil-earth materials factor that is responsible for the formation of zonal forest facies along the valley which undergo swamping at the final stage of their functioning. The progressive development of this regional process leads to marked changes of the biogeochemical situation, and to a deterioration of habitat quality. The problem is complicated by technogenic impacts on the landscape sphere of the oil and gas production complex of Western Siberia.  相似文献   

17.
《Geomorphology》1988,1(2):87-109
A model of denudation processes leading to relief inversion is developed for a section of the plunging anticline at Monte Nerone, in the Umbro-Marchean Apennines of central Italy. This model differs from previous schemes, as it applies to an anticline in which only the core consists of resistant rock. Furthermore, erosion, a combination of gullying and mass movement, is concentrated on the flanks rather than the crest of the fold, as strata dip steeply on the former yet are shallow on the latter. Whereas in most models of the geomorphic evolution of anticlines the crest is first to be eroded away, in the case of Monte Nerone it is preserved by scarp retreat from the upper flanks. Cuestas and flatirons have formed on the lower flanks and are in some cases affected by gravitational deformation. Phases of talus production, debris flowage and gullying have occurred in the valleys between the flatirons, thus dissecting the Cretaceous and Tertiary strata on the limbs of the anticline.The denudation of Monte Nerone shows similarities to and differences from other models of the geomorphic evolution of anticlines, and is related in this article to general neotectonic processes and Quaternary sedimentation.  相似文献   

18.
The stages of geomorphic development of mountains have sometimes been explained based on Strahler's diagram of hypsometric curves. Although the Japanese mountains are young, they do not follow his diagram. Hypsometric curves, simulated using empirical laws deduced from the Japanese mountains, indicate that mountain building resulting from concurrent tectonics and denudation does not produce convex curves but concave and/or s-shaped curves. The hypsometric curve of a mountain changes from a concave curve to an s-shaped curve in accordance with the increase in mountain altitude. The succession of the hypsometric curve during concurrent tectonics and denudation is the reverse of Strahler's diagram. The hypsometric integral increases with the advance in stage which is evaluated based on the change in mountain altitude. It has a relatively good correlation with the stage. However, the sequence of change in the hypsometric integral is different according to the extent of the terrain examined, whether the terrain is restricted to the interior of a mountain or pertains to the whole mountain, and whether it includes newly emerged land. The stage should be evaluated based on the course of change in the integral characteristics for the extent of the mountain examined.  相似文献   

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本文探讨了西伯利亚地区在苏联解体前后地缘政治经济格局的变化及其对外经济联系;分析了俄罗斯联邦独立以来西伯利亚积极调整伙伴关系,强化与世界市场接轨,寻求扩大对外经济联系的新途径和开辟新的通道;论述了改造西伯利亚铁路问题已迫在眉睫,建设北西伯利亚铁路势在必行,以及西伯利亚水上通道和空运在其今后对外经济联系中将发挥日趋重要的作用;提出了西伯利亚对外经济联系的对策。  相似文献   

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