Caspian Sea amphipods: biodiversity,systematic position and ecological peculiarities of some species     

Galina M. Pjatakova  Anatolyi G. Tarasov 《International Journal of Salt Lake Research》1996,5(1):63-79

In the Caspian Sea, one group of crustaceans, the Amphipoda, is represented by 72(70?) species, 60(58?) of which are gammarids, arranged in 20 genera. Almost all are endemic to the Ponto-Caspian zoogeographical region. To simplify the taxonomy of the genusGammarus Fabricius s.l., the Caspian gammarids ought to be grouped in 4 genera:Dikerogammarus Stebbing,Pontogammarus Sowinsky,Stenogammarus Martynov, andChaetogammarus Martynov. Taking into account the influence of different ecological factors on the external morphology of gammarids, we consider that all described forms ofDikerogammarus haemobaphes (Eichwald),D. villosus (Sowinsky),D. palmatus Martynov,D. fluviatilus Martynov, and perhapsD. aralensis (Uljanin) are one species —D. haemobaphes. Study of the ecological area and distribution ofIphigenella andrusovi Sars,Pandorites podoceroides (Grimm) andChaetogammarus placidus Sars indicates that these species are endemic to the Caspian Sea.  相似文献   

贝加尔湖Aulacoseira硅藻细胞壳的形态多样性及其在人类活动影响下的变化     

Olga Kozhov  Galina Kobanova 《湖泊科学》1998,10(S1):377-391

We have investigated the frustule ultrastructure of Baikalian Aulacoseira: A.baicalensis (K.Meyer) Sim. and of thin-wall, spore-producing Aulacoseira which has long been designated as A. islandica (O.Muller) Sim. or A.islandica ssp. helvetica (O.Muller) Sim. (now A.skvortzowii Edlund, Stoermer,Taylor). It was found that the disagreement on the name of spore-forming Aulacoseira is due to the destruction of its vegetative frustules in the process of breaking free of the organic content, while ultrastructure data on A.islandica from different Russia''s regions can reflect signatures of different species.A. baicalensis is characterized by great polymorphism. A. baicalensis starts its development from the initial cell (auxospore). The morphological characteristics of the frustule undergo the drastic changes in the course of the life cycle. It sequentially changes the morphology and structure of its valves. Its cells evolve through several stages of development:from cyclotella-like cells to narrow and short reproducing cells. In the influence zone of the Baikalsky Pulp-and-Paper Plant (BPPP), waste waters, disturbances in the frustule structure both in vegetative and generative cells have been detected.  相似文献   

A cellular-automata, slider-block model for earthquakes II. Demonstration of self-organized criticality for a 2-D system     

Jie Huang  Galina Narkounskaia  Donald L. Turcotte 《Geophysical Journal International》1992,111(2):259-269

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Model Radiants of the Geminid Meteor Shower     

Galina O. Ryabova 《Earth, Moon, and Planets》2008,102(1-4):95-102

This paper describes the final stage of the study of the Geminid meteoroid stream formation and evolution using the nested polynomials method reported by Ryabova (in: Warmbein (ed.) Meteoroids 2001, Proc. of the Internat. Conf., Kiruna, Sweden, 6–10 August 2001; MNRAS 375:1371–1380, 2007). In the previous work we discussed possibility to calibrate the model using the shape of the model activity profiles and configuration of orbital parameters. Here we show that the radiant structure also could be utilized for this purpose, since the model radiant structure has a very specific pattern. Model area of radiation does not have a “classical” prolate linear shape, and the configuration of activity centers has a “V” shape. During one night of simulated observations several activity centers could be observed. The model produced maps of the velocity distribution in the radiant area.  相似文献   

Climatic variations of general atmospheric circulation, precipitation and river flow of the territory of Kazakhstan     

Vitaly Salnikov  Galina Turulin  Svetlana Polyakov  Marat Moldahmetov  Lyazzat Mahmudova 《寒旱区科学》2013,5(1):0109-0113

Methods of calculating the basic hydrological characteristics of a water resource assessment, as well as the planning and management of their long-term use are based upon the concept of stationarity of long-term flow fluctuations. However, data of researches by hydrologists and climatologists clearly indicate that there are long-period changes in the characteristics of precipitation and river flow. This article discusses the variations of annual precipitation and river flow in the Ishim River Basin in Kazakhstan, based on the W, C and E classification developed by G.Y. Vangengeim who analyzed the long-term variability of anomalies by the number of days with some form of atmospheric circulation. From this study, the largest anomaly of the macro-circulation processes was revealed, and a comparative analysis of the number of days with various forms of atmospheric circulation and precipitation anomalies was made. It was demonstrated that the nature of atmospheric circulation depends on the distribution of precipitation; however, precipitation is also highly dependent on local physiographic conditions. The analysis of anomalous precipitation during the maximum number of days of positive anomalies with various forms of atmospheric circulation was also carried out. This study presents some results from the preliminary analysis of annual river flow linked with forms of atmospheric circulation.  相似文献   

The Cretaceous of the East Asian continental margin: Stratigraphy,paleogeography, and paleoclimate     

Galina L. Kirillova 《Island Arc》2011,20(1):57-77

Lithostratigraphic correlation of a 6–10‐km‐thick Aptian–Maastrichtian terrigenous sequence of the East Asian continental margin and Sakhalin and Hokkaido Islands has revealed the existence of a single marine basin. This basin was populated by mixed Tethyan–Boreal fauna and sloped eastward until the Middle Cenomanian. Intense volcanic and tectonic processes caused the uplift of the continental margin in the mid‐Albian to Cenomanian and eastward migration of the shoreline. Paleobotanical studies have discovered a number of climatic changes. Relatively warm conditions existed in the Aptian, changing to cooler conditions in the Early Albian. The maximum warming occurred from the Late Albian to Cenomanian when large‐leaved flowering plants dominated the population. In the Late Cretaceous, the East Asian volcanic belt created a mountain edifice up to 3000 m high, which controlled longitudinal climatic and floral zonation. This control was more efficient than the latitudinal control. A wide development of flowering Platanaceae flora in the Turonian points to a relative cooling. The floral assemblage shows a temperate climate from the Early Coniacian onwards, with an optimum in the Campanian that is consistent with global transgression. As a result of the warm climate, the early Maastrichtian is characterized by highly diverse biota. Furthermore, in the middle Maastrichtian floral and faunal diversity decreased and the seasonal prevalence increased. Cooling occurred in the latest Maastrichtian. Five periods of coal accumulation are recognized throughout the Late Cenomanian to Late Maastrichtian. Shelf, deltaic, and slope turbidite facies of the continental margin contain organic carbon ranging from 0.3% to 2.2%, which together with direct evidence for oil and gas, are believed to be prolific for hydrocarbon exploration.  相似文献   

Ab initio calculations of 6‐ and 7‐carbon meteoritic amino acids and their diastereomers     

Galina M. CHABAN  Sandra PIZZARELLO 《Meteoritics & planetary science》2010,45(6):1053-1060

Abstract– To better explain the unusual distribution and relative abundances of several 6‐ and 7‐carbon amino acids found in meteorites, their thermodynamic properties were studied using accurate ab initio techniques. In addition to optimized structures and relative energies, vibrational frequency and thermochemical analysis of different diastereomers were performed at temperatures relevant to conditions of synthesis of these amino acids in meteorites. The results of calculations were compared with the measured content of the amino acids in the Murchison meteorite. The distribution of several longer chain amino acids in meteorites seems to point to at least some thermodynamic control in their formation. For diastereomeric compounds, on the other hand, the comparison suggests that their synthetic conditions, or those of their precursors, were far from thermodynamic equilibrium.  相似文献   

Role of the Rossiter-McLaughlin effect in the study of close binaries     

Galina N.Dryomova  Vladimir V.Dryomov 《天文和天体物理学研究(英文版)》2019,(3)

This paper is devoted to binary stars belonging to the class of eclipsing-variable systems.Photometric and spectroscopic analysis of eclipses allows us to determine geometric parameters of the orbit and physical characteristics of stellar components as well as inclinations of stellar equators to the orbital plane. Estimations of inclinations can be obtained from measurement of the Rossiter-McLaughlin effect, which is discussed using examples of some eccentric binaries with an anomalous apsidal effect. Our task is to find the complete spectrum of solutions of the equation of apsidal motion, depending on the inclinations of the polar axes of the components to the orbital one for these systems, based on their individual spectroscopic and photometric observational data. The matrix of solutions allows us to select those pairs of polar inclinations that provide agreement with the observational apsidal period.  相似文献   

A word about the teacher     

Galina N.Dryomova  Olga V.Eretnova  Tatyana S.Polushina 《天文和天体物理学研究(英文版)》2019,(3)

This is a memorial report on the biography and scientific heritage of M.A. Svechnikov — an outstanding scientist and teacher, the founder of the Ural school of close binary stars and the author of the classification scheme for eclipsing variable stars.  相似文献   

Origin of REE-rich ferrocarbonatites in southern Siberia (Russia): implications based on melt and fluid inclusions     

Ilya R. Prokopyev  Alexander S. Borisenko  Andrey A. Borovikov  Galina G. Pavlova 《Mineralogy and Petrology》2016,110(6):845-859

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