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Theory and methodology
- Shpolyanskaya N.A.About the mechanism of formation of massive ice beds (critical analysis of segregation mechanism)
Genesis of large massive ice beds which are widely present on the northern plains of Russia is discussed. Underground ice is a source of all kinds of palaeogeographic information; therefore understanding of its genesis is of particular importance. Massive ice beds are an object of study since the 1960-s but their genesis is still a debatable point. There are several often controversial concepts, from the buried remnants of the ancient glacial cover to the direct submarine formation. According to an earlier concept massive ice beds are formed in the process of epigenetic ground freezing as a result of upward migration of ground water from the deep layers to the freezing level. The so-called segregation mechanism supported by molecular links of water in the ground is a principal one for formation of layered permafrost with texture-forming ice. The article presents a critical analysis of the mechanism in terms of its capability to form heavy ice layers. A lot of experimental data are available now and their analysis proves that molecular links could not support large-distance water migration to the freezing surface. Thus, no long-term constant inflow of water which is a prerequisite of a large ice body formation is possible. The migration flow covers just small distances and is several times interrupted during the ground freezing leading to the formation of dehydration zones. Therefore the mechanism is capable of forming individual ice sub-layers (schliers) within the permafrost rather than massive ice beds.
Geography and ecology
- Erina O.N. Prognostic evaluation of changes of the oxygen regime and water quality in the Mozhaisk reservoir under extremely hot weather
Quantitative assessment of possible changes of the hypoxia zone (with dissolved oxygen concentrations less than 2 mg/l) depending on water amount and synoptic conditions of the vegetation season was carried out for the Mozhaisk reservoir, the main element in the Moskva River water supply system of Moscow. Particular attention was given to the analysis of unfavorable hydrometeorological situations, such as combination of the low level of seasonal flood, hot anticyclone weather and small water input into the reservoir during the low-flow period. The spatial-temporal pattern of dissolved oxygen distribution was calculated using the hydrological model of the reservoir (HMR-MSU) with additional ecological unit. The oxygen unit of the model was verified basing on the data of 10 hydrological-hydrochemical surveys. Standard deviation of calculated values of dissolved oxygen concentrations from 609 measurements during the whole period of modeling (361 days) was ±2,1 mg/l and mean absolute error of model calculation was -0,6 mg/l. Scenario model calculations revealed different parameters of the hypoxia zone in relation to the timing of hot weather. A combination of medium flow, hot spring and low seasonal flood results in much lower oxygen concentrations in the reservoir as compared to a typical medium-flow year, because of the small amount of diatoms, earlier formation of stable thermal stratification and lower concentrations of dissolved oxygen under high water temperatures. Extremely hot summer weather may cause the formation of vast hypoxia zones in the hypolimnion layer (up to 36% of the total water amount) and affect water quality in the reservoir.
- Bezukhov D.A., Belyaev V.R., Ivanova N.N. Quantitative assessment of intensity and trends of erosion and accumulation processes on cultivated slopes within the Plava River basin (the Tula oblast)
The intensity of fluvial erosion and accumulation processes was evaluated for a small, mainly cultivated, catchment area within the Plava River basin (the Tula oblast, the Srednerusskaya Upland). Three independent approaches were applied to evaluate the material movement within the area: soil-morphological profiles, modified combination of USLE and GGI equation, radiocaesium method. Comparison of the results provided sufficient information for the calculation of sediment budget. The catchment under study has largely negative balance of sediments, i.e. about 80% of matter from the cultivated slopes is exported to the main river through the catchment outlet. The analysis of topographic maps and space images for different dates allowed reconstructing the history of land use of the catchment under study, i.e. identifying the arable lands for five time periods. A tentative scheme of the catchment area functioning during the period of the most intensive agricultural development (after the 1861 land tenure reform) is suggested. It takes into account the trends of self-evolution of the balkas system and the dynamics of land use types boundaries.
Methods of geographical studies
- Novenko E.Yu., Tsyganov A.N., Volkova E.M., Babenko K.V., Mazei Yu.A. Landscape and climate dynamics of the north-western Srednerusskaya Upland during the Holocenе
New results of complex palaeogeographical investigation of the Klyukva karst-suffosion bog (the Belev raion of the Tula oblast) and the reconstruction of the Holocene dynamics of vegetation resulting from climate changes and anthropogenic impact are presented. During the boreal period of the Holocene the territory under study was covered mainly by pine and birch forests, probably inherited from the periglacial vegetation cover of the Late Valdai Ice Age. The broadleaved forests appeared within the Upper Oka River basin about 7800 years ago (the Atlantic period) and about 7500 years ago oak, lime and elm forests with birch became the dominant component of the vegetation cover. Changes in bog vegetation, testate amoebas, characteristics of peat stratum and surrounding vegetation cover suggest that climatic conditions of the late Atlantic period (thermal maximum of the Holocene) were warmer and dryer as compared to modern ones, probably due to lesser summer precipitation. During the second half of the Holocene the most radical changes, both local (in bog ecosystems) and regional (in the Upper Oka River basin, the north-western part of the Srednerusskaya Upland), occurred 5000 and 2500 years ago, in line with the principal milestones of the natural environment evolution. Profound changes of the vegetation cover took place in the historical time as a result of the anthropogenic activities. Wide distribution of spruce during that period could be probably attributed to the anthropogenic impact rather than to climate change, because after the clearing of broadleaved species the spruce has gained in competitiveness.
- Malysheva N.V., Zolina T.A., Vladimirova N.A. Local cartographic service for visualization of the forest statistics of Russia
Data of sectoral statistical observations are included into the state forest register which integrates documentary information about forests, their use, protection and reproduction. Up to now the state forest register lacks the cartographic support. Our study is aimed at the improvement of the information support of the federal-level forest management by 1) practical application of GIS instruments for mapping and 2) use of web-technologies for map visualization and delivery to end users. Methods and experience of elaboration of a cartographic service for visualization of statistical data about the forests of Russia and their web-browsing are described. The content of the cartographic service includes layers with the data of the state forest register and a shortcut cartographic base with administrative-territorial units of the Russian Federation and territorial forest management units (forest districts). Maps were processed using ArcGis for Desktop ver. 10; prototypes were converted into SVG format by means of a special ArcGis add-in (Mappetizer 11.2). The atlas includes HTML-documents with embedded vector maps in SVG-format and pictures, as well as the scripts of scenario. Maps of the atlas are grouped into thematic sections and subsections, describing forests and forest resources, forest conservation and protection and forest reproduction. User interface in web-browser provides for viewing and printing the forest register data, switching on and off data layers, realize queries to spatial and attributive data. For users the atlas is a set of HTML-pages, hierarchically organized according to the sequence of acquiring information about forests (resource potential of a territory, forest use, conservation, protection and reproduction). A user could load these pages according to the predefined scenario turning them by web-browser similar to the Internet web-site pages. The computer atlas could be loaded on a local computer or server and is suitable for web publication. The suggested approach demonstrates that it is possible to produce cartographic representation of the state forest register data without installing expensive GIS software on the user’s server or local computer.
Regional studies
- Magritsky D.V. Spatial-temporal parameters of floods at the Black Sea coast of the Russian Federation
Floods, mainly of runoff and runoff-storm genesis, are among the most dangerous natural processes and phenomena at the Black Sea coast of Russia. They cause damage and considerable economic losses and even fatalities. Successful forecast of floods, their control or mitigation and minimizing related damage depend on the knowledge about the factors of floods, their mechanisms, geographical localization of affected areas, long-term dynamics, frequency and speed of flooding processes, efficiency of flood control measures, etc. Data reconstructed for the flood and inundation events and their principal parameters formed the information base for the detailed analysis of the present-day flooding situation at the Black Sea coast of the Russian Federation and its evolution during 1945-2013. Principal features of the origin and progress of high water episodes and resulting runoff and runoff-storm floods were revealed for the Black Sea rivers; general parameters of such floods were obtained. Original maps of the maximum possible water rise above the pre-flood level and of settlements affected by flooding of different frequency were compiled. Trends and causes of annual and long-term changes in genesis, number and parameters of floods, as well as their spatial correlations were identified for the coastal municipal districts. Results of the study could be useful for improvement of the system of flood control and prevention measures.
- Chizhova Yu.N., Budantseva N.A., Rets E.P., Loshakova N.A., Popovnin V.V.,Vasilchuk Yu.K. Isotopic variation of runoff from the Dzhan Kuat glacier (Central Caucasus)
The isotopic variation of glacial runoff from the Dzhankuat glacier (Central Caucasus) during the 2013 summer season is described. The season was abnormally rainy with resulting non-typical form of the Dzhankuat River hydrograph. The contribution of melting glacier ice to the total runoff was qualitatively assessed. Studying the input of glacial melt water into the runoff is a key element of integral hydroclimatic approach to the monitoring of glacier basins. In summer 2013 the d 18O of the Dzhankuat River water varied from -15,04‰ in June to -11,27‰ in September. The basic component of runoff in the end of ablation season has d 18O = -11,9‰. Low values of d 18O (-14…-15‰) for the glacial runoff in June correspond to the melting of isotopically negative winter and early spring snow and glacier ice. The increasing d 18O values of river water (more than -12‰) in September probably indicate a predominant role of subglacial water and groundwater in runoff formation during the period of decreasing intensity of ice ablation. Daily isotopic variations of runoff are negligible.
- Temirgaleev R.F. Impact of immigration on the changes of spatial distribution of ethnic and racial population groups in the USA during the 2000-s
The USA 2010 Census data were analyzed in terms of the ethnic and racial situation. General pattern of population distribution, ethnic and racial composition of population in particular states and statistical areas, its transformation within the urban space, internal migration of population and the immigration are discussed both in temporal dynamics (considering 2000 and 2010 census data) and in spatial interrelations (for states and statistical areas). The first conclusion is about the stability of the spatial pattern of population growth rates in the USA. At the same time it was revealed that during 2000-2010 the largest states increased their population much slower than the least populated ones which demonstrated the highest population growth rates. Four principal ethnic and racial groups (American Europeans, Latinos, Afro-Americans and Asians) become more and more evenly distributed over the USA territory. The immigration is persistently high in that country and according to different estimations the immigrants account for ½ to ¾ of the total population growth. Meso-Americans are predominant group of immigrants to the USA. In the past they settled mainly in the states near the Mexican border, but recently they became dispersed over the whole territory of the country.
- Gerasimova M.I., Kasimov N.S., Gorbunova I.A., Bogdanova M.D., Ryabova N.V.,Lychagin M.Yu.Landscape-geochemical regionalization of the Selenga River basin
A map of landscape-geochemical regionalization of the Selenga River basin (scale 1:2,5 M) was compiled to study factors and processes of geochemical flows formation and modification. Traditionally the zonal approach is used for landscape-geochemical regionalization of vast territories, which it into account the general parameters of biological cycle of matter and the classes of water migration. Within the Selenga River basin the predominant relief of mountains and depressions is combined with the complicated geological structure, varied lithogeochemical background, contrasting climatic conditions and several spectra of altitudinal zones. Therefore, it is lithological-morphological factor governing the nature and trends of migration processes that became a principal criterion for identifying the main territorial units of landscape-geochemical regionalization of the basin. The system of landscape-geochemical regionalization of the basin includes three hierarchical levels with different criteria of identification. The two upper levels are of typological character and represent general physical-geographical conditions of geochemical migration processes. The units of the lower level were identified with the account of complex combinations of local conditions within the framework of general lithological-morphological and climatic prerequisites of migration, accumulation and input of matter into river systems. Combination of typological and regional approaches stems from a wide variety of natural conditions and geochemical migration features within the area under study. Methodological bases of regionalization may be helpsul for the landscape-geochemical studies of mountain territories.
- Myslenkov S.A., Zatsepin A.G., Silverstova K.P., Baranov V.I. Coastal dynamics of the Black Sea shelf zone investigated by drifting buoys and towed ADCP
The sea current monitoring system consists of drifting buoys with GPS receiver and GSM connection was created. The results of testing this system are presented in this paper. One of the main advantages is high temporal and spatial scale of the data furthermore there is option of real time observation due to GSM-connection. Surface currents of the Black sea shelf zone are studied near Gelendzhik. Data are obtained from drifting buoys and towed ADCP (Acoustic Dopler Current Profiler). Three experimental launches of buoys and result of comparison their trajectories with velocity field from ADCP are presented. Experimental time varies from hours to 2 days. There is also information about wind velocity and direction for each experiment. Buoys launched 30-40 m one from another were moving quasi-parallel for 5-10 hours during one of the experiments. Thus parallel jet currents were identified in the studied area. A dipole typical for sub-mesoscale eddy dynamics was observed during another day. The dipole was probably formed as a result from energy dissipation and destruction of eddy marked in the beginning of this experiment. There was no correlation between wind and currents in previous case. Third experiment shows that wind and current had the same direction. In conclusion eddies have temporary influence on coastal water dynamics. Coastal currents described by drifting buoys matches with ADCP data in general, but application of different methods leads to different interpretation of circulation. The experimental data prove the efficiency of presented monitoring system, which allows study coastal currents. There is a future research plan for extended experiments.
Jubilees
- Jubilee of Emma Petrovna Romanova
- The 70th anniversary of Evgeniy Konstantinovich Semenov
Obituary
- Alla Konstantinovna Danilenko
Версия для печати
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