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971.
M. M. Ivanov N. N. Ivanova V. N. Golosov E. N. Shamshurina 《Geography and Natural Resources》2016,37(4):355-361
We examine the use of two alternative techniques for assessing the redistribution volumes of sorbed 137Cs within the upper components of the fluvial network, based on the concept of catchment as a lithodynamical system. In terms of one of them, we made a substantive analysis of changes in reserves on accumulative positions where the 137Cs distribution curves showed a significant increase in radionuclide content levels. We carried out a typization o the accumulation surfaces in order to extrapolate data, obtained for a group of soil profiles, to the territory of the entire catchment and to make a direct assessment of the increases in accumulation. An alternative technique was used to assess the volumes of accumulated sediment loads on accumulative positions by analyzing the 137Cs distribution curves, and to correlate with denudation zones in the drainage area under consideration. Values of the wash-out rates for the period 1986–2012 have been obtained, which are necessary for the formation of the accumulative layer observed. We calculated the volume of 137Cs swept away during 26 years after the Chernobyl accident, based on information regarding the volumes of initial reserves in the denudation zones and a correlation between the erosion rate and a specific reduction in reserves. It is established that the technique on the basis of analyzing the wash-out zones featuring high economical efficiency can be used in assessing 137Cs migration for larger territories with relatively low labor-consuming effort. 相似文献
972.
973.
We examine the intrasecular morphodynamics of the Irkut river within the Tunkinskaya depression and the associated partitions between depressions. An analysis is made of the changes in the channel pattern in plan, and a typization is provided for the channel processes for three time intervals: 1914, 1975 and 2015. We identified eleven morphodynamically uniform reaches of the channel: three, one and seven of them are of the adapted, incised and broad-floodplain types, respectively. The types of morphodynamical development of the river are systematized, and reaches with a different degree of deformation are identified within the most mobile broad-band segment of the river in conditions of free meandering. It is ascertained that the reaches of the braided type and the reach with sharp loop-like bends are the most stable, which is, in either case, due to the consolidation of vegetation by the high floodplain which made it possible to stabilize the movement of the channel in plan. The most strongly altered reaches are determined, where river channel displacements were accompanied by a complete change of the morphodynamical types of bends; the macrobends mainly experienced a regular breakthrough or were complicated by lower-order bends. We identified the reaches with lower-order (local) changes where the development of the bends (for the most part, of the loop-like type) changed into a new evolutionary cycle). We determined the role played by the influence of the territory’s geologo-geomorphological structure, hydrological conditions and natural processes of channel evolution on the dynamics of homogeneous reaches, and on morphological changes within them. The period of the most significant channel deformations, from 1914 to 1976, was determined, which is accounted for by an enhancement in anthropogenic pressure and by the associated increase in suspended load, and the period of decrease in the magnitude of manifestations of channel deformations from 1976 to 2015. 相似文献
974.
D. V. Lisitskii 《Geography and Natural Resources》2016,37(4):296-301
This paper is concerned with some issues related to the changes in the role, properties and characteristics of cartography in connection with the transition of mankind from the industrial age to the information (post-industrial) age. Emphasis is placed on the essence of the process of perception of the environment by humans through data provided to them where the object of perception and the subject perceiving information are located at different points of the space-time continuum. The study identifies eight characteristic features of the information age, the new challenges and requirements, the possibilities of information society, and the related new tasks of cartographic support of the economy. It is shown that the main difference of the information age from the industrial age implies a transition from the commodity-producing economy to the economy of information services. Based on this, it is concluded that there is a need for the provision of various cartographic services, such as the generation of cartographic information as requested as well as supplying it to various users. Seven main statements are formulated, which characterize the peculiarities, properties and methodological foundations of cartography under the new conditions. The definitions of the role and subject of cartography in the information age are suggested. An interpretation is given to the term “neocartography”, and its main characteristics are presented. The notion of a multipurpose cartographic resource is introduced. 相似文献
975.
F. L. Brazhalovich M. I. Klyuchnikov A. I. Lukyanov 《Geography and Natural Resources》2016,37(3):264-270
We examine the phenomenon of “collapsed” states by using, as an example, Somalia that is being faced with a vast array of problems: collapse of state institutes, civil war, separatism, terrorism, radical Islamism, and piracy. It is found that clannishness and tribalism of Somali society are complicating the process of political settlement and national reconciliation. It is pointed out that some of the tribes and groups, including under the action of external forces, are actually forming the country’s political space. It is shown that the pseudo-state entities in Somalia are unstable, and their boundaries of “flowing” so that they are incapable of exercising a full control over the territory. It is emphasized that the problem of Islamic extremism can be treated as deriving from failure of the state institutes; the peak of activity and territorial expansion of Islamist groups in the country is now in the past, and the area of their activity is bounded by the area inhabited by the Somali ethnos. It is found that the piracy problem is determined by the geographical location of Somalia, and its solution is impossible without the reestablishment of the state institutes and the economic system of the country. Two potential cores of reestablishment of Somali statehood have been revealed: Federal Government in Mogadishu as well as the Autonomous Republic of Puntland. It is forecasted that the international community will be gradually recognizing the Republic of Somaliland. It is concluded that the federalization of the country as declared by authorities is formal in character but yields first results implying that the negotiation process between the groups of clans has been led into a political channel. 相似文献
976.
K. S. Ganzei 《Geography and Natural Resources》2016,37(3):257-263
The dynamics of land use in Russkii Island is considered for the period from 2007 to 2014, and some issues of its future development are analyzed. The areas of lands of different categories and the maps of land use on the Sapernyi Peninsula are provided for different time spans. It is established that the implementation of the program of the preparation of Vladivostok for APEC Summit 2012 led to a substantial change in the land use pattern in Russkii Island: the area not involved in the economic turnover decreased by 5.09%, the zone of production, engineering and transport infrastructure increased by a factor of 21.5, and the share of lands for recreational purposes increased more than twice. It is shown that recreational activities implying a decrease in the share of lands not drawn into the economic turnover by more than a factor of 5 must become the dominant kind of land use (according to the program of development of Vladivostok). Attention is focused on the issue related to the creation of the territory of priority socioeconomic development in Russkii Island through the use of private-state partnership mechanisms. It is pointed out that the implementation of the development plans for the island is delayed, in spite of the legislative and financial support from federal and regional authorities. Emphasis is placed on the need to develop the program of comprehensive substantiation, modeling and forecasting of the development of Russkii Island in the interests of the sustainable functioning of the natural-economic system. 相似文献
977.
An analysis is made of the manifestations of fluvial and aeolian processes in the southern, developed areas of Irkutsk oblast belonging to the upstream part of the Angara basin. We examine the formation probability and the recurrence frequency of disastrous geomorphological events. The study revealed their association with positive (fluvial processes) and negative (aeolian processes) extremes and anomalies of atmospheric moistening. It is shown that at the time of an extreme event the rate of the processes and the volumes of transported material increase abruptly (by an order of magnitude), and the affected areas show an increase. The criteria for an extreme fluvial event can be represented by a spasmodic buildup of gullies and appearance of new gullies, an abrupt increase in soil losses due to erosion of agricultural lands reaching 100?200 m3/ha, death of crops, releases of mud flows, and destruction of roads, dams, bridges and other structures. The geomorphological consequences of the 1960 summer storm rains are considered to exemplify the disastrous fluvial events. The extremes of aeolian processes have the character of hurricanes encompassing most of the agricultural areas of Irkutsk oblast. The hurricanes are accompanied by a powerful removal of aeolian material from north-west to south-east to the water area of Baikal, to windward slopes and watershed divides of the mountain ranges along the eastern coast. The finest dust particles are transported to neighboring areas of Buryatia, Mongolia and China. The negative consequences of extreme aeolian events include agricultural crop destruction or damage, soil deflation, pollution of surface waters by deflation products, fires, damage to power transmission lines or even death of people. The findings were used in zoning the Upper Angara region according to the degree of geomorphological security of the territory. 相似文献
978.
L. M. Sorokovikova V. N. Sinyukovich I. V. Tomberg G. I. Popovskaya N. V. Bashenkhaeva N. P. Sez’ko N. A. Zhuchenko 《Geography and Natural Resources》2016,37(3):220-227
Field observations showed that the characteristics of chemical composition of waters and the development of plankton algae in the lakes within the delta of the Selenga river are determined by their flowage. The most open Lake Nekipelovskoe communicates with the Selenga outlets throughout a year, and Lake Zavernyaikha only at the period of an open channel. Lake Semenovskoe and Lake Khlystov Zaton are located in the islands and are isolated from the outlets. According to composition of main ions, the lakes under investigation refer to the hydrocarbonate class, the calcium group. The sum of ions in the water of Lake Nekipelovskoe approaches the one in the Selenga (86?221 mg/dm3), and the highest sums of ions were recorded in the wintertime in the lakes isolated from the outlets (446?743 mg/dm3). The lakes of the delta are characterized by a high trophicity. The maximum concentrations of total phosphorus in Lake Nekipelovskoe and Lake Zavernyaikha were 68 and 122 μg mg/dm3, and in Lake Semenovskoe and Lake Khlystov Zaton ?0.8 and ?0.63 μg mg/dm3, respectively. The most intense development of algae is observed in Lake Zavernyaikha, which is due to the high population of Baikal endemics. Lake Zavernyaikha showed a close negative correlation between the concentration of NO 3 ? , mineral phosphorus and phytoplankton biomass; the correlation coefficient was ?0.8 and ?0.63, respectively. The lakes exhibited increased contents readily hydrolysable organic matter, and a decrease in dissolved oxygen concentration in winter; hydrogen sulfide was repeatedly recorded in Lake Khlystov Zaton. The water quality in the lakes during the springtime varies from “quite clean” to “weakly polluted”; at low-water periods, especially in winters, it can drop to the category of “exceedingly dirty”. The water quality of the Selenga can be influenced by the lakes during spring floods when material accumulated during the wintertime is transported to the river outlets and further to Lake Baikal. 相似文献
979.
D. A. Burakov I. N. Gordeev A. V. Ignatov O. E. Petkun L. A. Putintsev A. A. Chekmarev 《Geography and Natural Resources》2016,37(2):158-164
We consider the various methods of constructing models intended to forecast the average water inflow, in the second quarter of the year, into two reservoirs on the Yenisei river. To solve modeling problems used a new computer technology implemented in the specialized “Stochastic Modeling” software package. Independent data were employed to verify the variants of the models for the formation of variability in quarterly inflow as generated based on different algorithms. A more sophisticated and robust model for forecasting the inflow was constructed as an ensemble of partial models. Based on aggregate results of modeling, we suggest the method of constructing a forecast of the average (for the second quarter) lateral inflow into the Krasnoyarsk reservoir and the inflow into the Sayano-Shushenskoe reservoir by use of observational data accumulated by Srednesibirskoe UGMS (Weather Control and Environmental Monitoring Service), based on an ensemble of partial models. It is established that such an operation reduces the probability of forecasting errors implying an arbitrary selection of models. We constructed forecasts of the aforementioned characteristics using real-time data for 2015. It is stated that the solution of the forecasting problem can be facilitated by using additional information. 相似文献
980.
А. T. Barabanov 《Geography and Natural Resources》2016,37(2):106-113
An analysis is made of the chief causes for degradation of agricultural lands: exhaustive agricultural land use, poor planning quality of land use management, deforestation, low volumes of forest planting and reforestation, and a high degree of plowing of lands. The principles of adaptive-landscape generation and land use practices are substantiated on the basis of a system approach to the exploitation of the natural-resource potential and a package of anti-degradation measures. The structure flowchart is given for the model of adaptive-landscape generation as developed on the basis of assessing the natural-climatic conditions, land resources, the degree of land degradation, and analyzing the set of indicators and criteria for a classification of landscapes. It is found that the key elements of the adaptive-landscape organization of land use on slopes are a typization of lands, the determination of the land use pattern, and the employment of technologies, methods and measures to ensure a normal functioning of agroecosystems. The following groups of lands are identified: gentle near-watershed slopes with a steepness of up to 2–3°; near-network lands, the lower boundary of which runs along the edge of the hydrographic network, and lands on the hydrographic network. The schematic of the organization of a large balka catchment is provided. 相似文献