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1.
Lyudmila V. Malakhova Viktor N. Egorov Tatiana V. Malakhova Sergey B. Gulin Yury G. Artemov 《Geo-Marine Letters》2010,30(3-4):391-398
Concentrations of dissolved methane in seawater and bottom sediments, as well as of methane emanating from gas seeps were measured at 18 stations including several small bays in the Sevastopol coastal area (Black Sea) during 2007–2008. Methane concentrations in surface waters ranged from 10 to 2,970 nmol l?1, and correlated well with values recorded for sediments. Methane concentrations in the water column were influenced by water depth, as well as by air and water temperatures. In the spring and summer of 2008, in situ CH4 saturation relative to air was in the range of 970–71,900%. Maximum saturation was in summer. CH4 fluxes to the atmosphere from the Sevastopol coastal area were estimated to vary from 190 to 1,550 μmol m?2 day?1. Gas bubbles escaping from the seepages contained about 57 vol% methane. Radiocarbon dating of the methane revealed an age not exceeding 150 years, implying a biogenic origin. 相似文献
2.
Gated communities of the Moscow green belt: newly segregated landscapes and the suburban Russian environment 总被引：3，自引：0，他引：3
The transition from the Soviet to the post-Soviet period in and near Moscow manifested itself in increasing production of
segregated space both in the urban core and suburban areas outside of the beltway to accommodate the preferences of the new
Russian business and governmental elite. This paper focuses on the residential single-family housing inside old and new settlements,
which are frequently gated. Approximately 260 of such suburban communities have been developed within 30 km of the beltway
during the past few years, of which a majority have some form of exclusion mechanism in place, typically tall solid fences,
gates, closed-circuit video surveillance and guarded entry checkpoints. The difference in exclusivity varies from the most
exclusive older communities inside Moscow Serebryany Bor enclave and Rublevskoe highway mansions to less exclusive new developments
along Novorizkhskoe and Dmitrovskoe highways. Despite high rates of construction, based on sociological surveys in 2003, only
about 11% of Russia’s upper class claimed to live in such new “cottages,” with the rest owning condos and luxury apartments
in the inner city or older detached homes in villages and small towns. Therefore, not all the needs have been accommodated
and more development is certain to take place. The environmental impact of such developments is profound. Based on preliminary
LANDSAT image analysis, almost 22% of suburban “green belt” forested land within 30 km zone has been converted to new construction
from 1991 to 2001. New construction is now focusing on the remaining fragments of natural vegetation, which will likely lower
air quality and water quality available for the city. Ironically, the new developments advertise themselves as “clean and
green” with massive investments in unnatural landscaping (seeded lawns, exotic shrubs, river and lake shore “improvements”).
This investment highlights the well-known paradox of development in which people move out of town to live near nature, while
destroying the wild nature they come to enjoy.
“We left city for the weekend
It was raining, saw no stars
There were fences everywhere
Our chiefs behind the bars.”
Gennady Shpalikov 相似文献
3.
Dmitriy V. Alexeiev Harry E. Cook Vasiliy M. Buvtyshkin Lyudmila Y. Golub 《Comptes Rendus Geoscience》2009,341(2-3):287-297
The deformation history of the Late Palaeozoic Ural–Tian Shan junction is discussed for the example of the Karatau ridge in southern Kazakhstan. Three deformation events are recognized. The Late Carboniferous D1 event is characterized by Laramide-style thrust-and-fold structures on the southern margin of Kazakhstan with shortening in a NE–SW direction. The Latest Permian and Triassic D2 event is controlled by compression in an east–west direction, which reflects collisional deformation in the Urals. The main structures are submeridional folds and north–west-striking sinistral strike–slip faults. The Triassic D3 event with shortening in a north–south direction reflects collision of the Turan microcontinent against the southern margin of Kazakhstan. The main structures are north–west-striking dextral strike–slip faults. Our new data provides important clues for the reconstruction of pre-Cretaceous structures between the Urals and the Tian Shan. 相似文献
4.
Yoko-Dovyren层状纯橄岩-橄长岩-辉长岩地块位于西伯利亚克拉通南部的一处褶皱构造框架中(俄罗斯贝加尔湖地区北部)。该地块的结构在其厚度最大的中部得到了着重研究。剖面底部主体成分为斜长橄榄岩,并依据内部的堆晶成分变化从下往上可分为五个主要的地层序列:纯橄岩→橄长岩→橄榄辉长岩→橄榄辉长苏长岩→石英辉长苏长岩以及含易变辉石的辉长岩。该地块的矿化包括铜-镍矿化、低硫型富铂族元素(PGE)矿化以及铬铁矿化等。另外,该地块也含多种非金属矿物原材料,如硼矿化、透辉石、各种镁质硅酸盐岩等。它们也包括纯橄岩、异剥橄榄岩和橄长岩,并以较高的品质产出,有望采掘加工成为建筑材料(水泥、混凝土、沥青混凝土和建筑陶瓷)。综合利用矿物原材料可增加矿床价值,并有助于建设环保型采矿工作体系。 相似文献
5.
In view of increasing lead pollution (Pb2+) of coastal waters, the compensatory abilities of holothurians need to be assessed. The goal of the work is to clarify the functional and phenotypical differences between two types of phagocytes (P1 and P2) in Eupentacta fraudatrix exposed to Pb(NO3)2. It has been shown that 2 mg L?1 lead exposure for 48 h increases the number of P2 phagocytes as compared to P1 cells, does not significantly affect cell viability in both P1 and P2 phagocyte fractions, and significantly enhances chromatin condensation in P2 but not in P1 phagocytes. A lead concentration of 4 mg L?1 increases the number of P1 phagocytes compared to that of P2 type, and does not change cell viability and chromatin condensation in P1 phagocytes. In the P2 type, it decreases cell viability and does not influence the level of apoptosis. The protection against lead-induced apoptosis is apparently mediated by the activities of antioxidant enzymes, especially glutathione S-transferase. The differences in labeling cell surface receptors of P1 and P2 phagocytes by plant lectins also indicate the specific phenotypic properties of these cells. The results clarify the potential and GSH-dependent mechanisms of immune adaptation in holothurians that have been shortly exposed to lead at concentrations close to the maximum environmentally relevant level in coastal waters. Additionally, P1 and P2 phagocytes are first shown to have different functions and phenotypes during the response to lead, which indicates the complexity of the phagocytic system in holothurians and contributes to understanding the immunity evolution. 相似文献
6.
Irina V. Kurina Elena E. Veretennikova Anna A. Il’ina Marina L. Egorova Lyudmila V. Salisch Vladimir N. Dolgin Albert V. Udaloi Evgeniya A. Golovatskaya Egor A. Dyukarev Sergei V. Smirnov 《Boreas: An International Journal of Quaternary Research》2023,52(2):223-239
Palaeoenvironmental reconstructions from peat are strongly focused on ombrotrophic mires, but this study demonstrates that eutrophic mires can also be used. A multi-proxy approach was applied to a eutrophic mire on a floodplain terrace in the southern taiga of West Siberia. The results of the reconstruction were considered in the wide geographic context of the surrounding regions, including Siberia and Central Asia. Different palaeoecological proxies (analysis of plant macrofossils, testate amoebae, oribatid mites, molluscs, peat humification, ash content and spectral characteristics of humic acids) were used in this study. The results of different proxies showed a high level of consistency among themselves, which allowed for a robust interpretation of Holocene mire development. Throughout the ~7800 years history of the mire, there was a high level of surface wetness. The presence of mineral matter in the peat between 7800 and 5100 cal. a BP indicates regular flooding caused by the intensive fluvial activity, apparently resulting from increased precipitation. This was followed by a trend towards a gradual decrease in surface wetness from conditions of high surface moisture (stagnant water) between 5100 and 3000 cal. a BP to present day conditions of moderate surface moisture with a water table slightly below the mire surface. This pattern is consistent with the well-documented long-term trend from palaeoecological records throughout the taiga and arctic zones in West Siberia and central arid Asia. Our data further support the idea that the westerlies were the dominant driver of climate for the southern taiga of West Siberia during the Middle to Late Holocene. 相似文献
7.
Andrei V. IVANOV Glenn J. MACPHERSON Michael E. ZOLENSKY Nataliya N. KONONKOVA Lyudmila F. MIGDISOVA 《Meteoritics & planetary science》1996,31(5):621-626
Abstract— Metal nodules are one of the major textural components of Kaidun sample #01.3.06 EH3-4. In terms of structure, the nodules are of three types: (1) globular, (2) zoned with a massive core and globular mantle, and (3) nodules with no internal structure. The size and composition of the globules in the nodules and grains of metal of the matrix are almost identical: no greater than 20 μm and Ni, 5.95; Si, 3.33 wt%. The nodules contain small (usually <5 μm) inclusions of SiO2; albitic glass; enstatite; roedderite; and a mixture of SiO2 and Na2S2. This is the first reported occurrence of a simple sulfide of an alkaline metal in nature. The formation of the inclusions appears to be related to condensation of material onto the surfaces of metal grains. The nodules appear to have formed by aggregation of separate grains (globules) of metal, with conservation of condensates on the grain surfaces as inclusions. The inclusions probably condensed over a significant temperature range from 1400 to 600 K. The aggregation of metal grains and formation of the nodules probably occurred simultaneously with condensation. 相似文献
8.
Lyudmila V. Yavorovich Anatolii A. Bespalko Pavel I. Fedotov Rina B. Baksht 《Acta Geophysica》2016,64(5):1446-1461
The paper presents an experiment on acoustic excitation of electromagnetic radiation (EMR) signals in skarn, sandstone, and magnetite ore samples. For the skarn and sandstone samples, the EMR signal amplitude was observed to decrease with increasing ultimate strength. Supposedly, this effect can be explained by assuming that EMR is generated when an acoustic wave propagates through an electrical double layer. The presence of piezoelectric inclusions (e.g., quartz) in the magnetite ore enhances the analog EMR signal and its spectral components. 相似文献
9.
Lyudmila S. Shumilovskikh Monika Schmidt Mikhail Pereskokov Pavel Sannikov 《Boreas: An International Journal of Quaternary Research》2020,49(3):526-543
The Ural Mountains are an important climatic and biogeographical barrier between European and Siberian forests. In order to shed light on the postglacial formation and evolution of the boreal forests in the European pre-Urals, we obtained a peat sediment core, Chernaya, from the Paltinskoe bog located between the southern taiga and hemiboreal forest zone in the mid-Kama region. We carried out pollen analysis, non-pollen palynomorph analysis, loss-on-ignition tests and radiocarbon dating. Radiocarbon dated records provide centennial to decennial resolution of the vegetation and environmental history of the European pre-Urals for the last 8.8 ka. The postglacial formation of the pre-Uralian hemiboreal forests reveals four important phases: (i) the dominance of Siberian taiga and forest-steppe in the Early Holocene and beginning of the Middle Holocene (8.8–6.9 ka), indicating a dry climate; (ii) the spread of spruce and European broadleaved trees in the Middle Holocene (6.9–4 ka) under wetter climate conditions; (iii) the maximum extent of broadleaved trees coinciding with the arrival and spread of Siberian fir in the Late Holocene (4–2.3 ka); and (iv) the decline of broadleaved trees since the Early Iron Age (2.3 ka – present) possibly due to general climate cooling and logging. While temperate broadleaved trees possibly spread from local refugia in the Urals, fir arrived from Siberia and spread further west. The carbon accumulation rate of Paltinskoe bog (18.9±10.16 g C m−2 a−1) is close to the average value of carbon accumulation of northern peatlands. Local development of peat is characterized by non-gradual growth with a phase of intensive carbon accumulation between 3.5 and 2.3 ka. The vegetation was strongly influenced by fire in the Early Holocene and by humans since the Early Iron Age practicing deforestation, agriculture and pasture. Phases of increased anthropogenic activity correlate well with the local archaeological data. 相似文献
10.
Albert F. Kurbatskiy Lyudmila I. Kurbatskaya 《Meteorology and Atmospheric Physics》2009,104(1-2):63-81
A modified three-parameter model of turbulence for a thermally stratified atmospheric boundary layer (ABL) is presented. The model is based on tensor-invariant parameterizations for the pressure–strain and pressure–temperature correlations that are more complete than the parameterizations used in the Mellor–Yamada model of level 3.0. The turbulent momentum and heat fluxes are calculated with explicit algebraic models obtained with the aid of symbol algebra from the transport equations for momentum and heat fluxes in the approximation of weakly equilibrium turbulence. The turbulent transport of heat and momentum fluxes is assumed to be negligibly small in this approximation. The three-parameter $E - \varepsilon - {\left\langle {\theta ^{2} } \right\rangle }$ model of thermally stratified turbulence is employed to obtain closed-form algebraic expressions for the fluxes. A computational test of a 24-h ABL evolution is implemented for an idealized two-dimensional region. Comparison of the computed results with the available observational data and other numerical models shows that the proposed model is able to reproduce both the most important structural features of the turbulence in an urban canopy layer near the urbanized ABL surface and the effect of urban roughness on a global structure of the fields of wind and temperature over a city. The results of the computational test for the new model indicate that the motion of air in the urban canopy layer is strongly influenced by mechanical factors (buildings) and thermal stratification. 相似文献