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1.
Moiseenko K. B. Berezina E. V. Vasileva A. V. Shtabkin Yu. A. Skorokhod A. I. Elanskii N. F. Belikov I. B. 《Doklady Earth Sciences》2019,487(2):981-985
Doklady Earth Sciences - Estimates of the photochemical ozone generation rate, PQ, and the ozone production efficiency (OPE) per molecule of NOx (=NO + NO2), ∆P, are obtained for the region... 相似文献
2.
Analysis is given of the modern approaches and methods used to assess the quality of bottom deposits based on the conditions of bacterio- and zoobenthos communities. The structural characteristics of bacterio- and zoobenthos communities of small rivers in the Upper Volga basin are studied. The type of substrate is shown to have appreciable effect on the quantitative characteristics of both the communities. The analysis of these data is used to create a generalized classification of the quality of bottom deposits and assess the extent of their pollution in the examined water bodies. 相似文献
3.
N. I. Berezina V. I. Dmitriev N. A. Merschikova 《Izvestiya Physics of the Solid Earth》2013,49(3):350-355
We consider the iterative numerical method for solving two-dimensional (2D) inverse problems of magnetotelluric sounding, which significantly reduces the computational burden of the inverse problem solution in the class of quasi-layered models. The idea of the method is to replace the operator of the direct 2D problem of calculating the low-frequency electromagnetic field in a quasi-layered medium by a quasi-one dimensional operator at each observation point. The method is applicable for solving the inverse problems of magnetotellurics with either the E- and H-polarized fields and in the case when the inverse problem is simultaneously solved using the impedance values for the fields with both polarizations. We describe the numerical method and present the examples of its application to the numerical solution of a number of model inverse problems of magnetotelluric sounding. 相似文献
4.
Changes in life cycle of the Ponto‐Caspian amphipod Pontogammarus robustoides at in the northernmost part of its range 
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下载免费PDF全文 Nadezhda A. Berezina 《Marine Ecology》2016,37(6):1434-1446
The aim of this study was to investigate the dynamics of abundance, population structure and reproductive variables of the invasive Ponto‐Caspian amphipod Pontogammarus robustoides in its northernmost population, located in the Baltic Sea. Pontogammarus robustoides population variables were studied every month from May to October over 7 years (2002–2008) at two locations in the eastern part of the Gulf of Finland, one site in the north and one in the south. Observations of macrozoobenthos were also conducted once per year in July at 12 sites in this gulf during 2002–2014. This was to monitor the distribution area of P. robustoides and its abundance/biomass in different parts of the Gulf. The results showed that P. robustoides is a widely spread species in the Gulf, preferring to colonize stone‐sandy, vegetated and littoral habitats, from the shore to a depth of 5 m, with water salinity of 0.2–3 ppt. This species co‐exists with other amphipods, such as the Baikalian Gmelinoides fasciatus, the North Atlantic Gammarus tigrinus and the native Gammarus spp. The abundance of P. robustoides varied between the two study sites and among years (2002–2008), reaching a maximum level of 1000 ind.·m?2 for adults and 3000 ind.·m?2 for juveniles. The temperature‐dependent duration of egg development (embryogenesis) in the amphipod and the annual number of generations in P. robustoides populations varied among years. Three generations were recorded in most years and two generations in the coldest years. Clutch size (or fecundity) was dependent on the body length of female and averaged between 33 and 43 eggs per clutch for females ranging in body length from 11.2 to 12.2 mm. A maximum of 75 eggs were observed in a female with a body length of 16 mm. This paper concludes that life‐cycle variables change when P. robustoides spreads from the southern (Ponto‐Caspian region) to northern (Baltic Sea) range areas. In the studied northernmost location, the fecundity and number of generations of this amphipod were 1.5–2‐fold lower compared with the more southern locations. In addition, these variables and P. robustoides abundance were different between the coldest and warmest years at study sites that testify about their distinct dependence on local environmental conditions; further changes in life cycle of this species may be expected together with current climate warming. 相似文献
5.
Water quality and the levels of pollution in biological communities of the Kotorosl' River and its major tributaries (the Sara, Lakhost', Mogza, and Pakhma rivers) are estimated by using a considerable body of hydrobiological characteristics (the Pantle–Buck saprobity index and its modifications by Rotshain and the indices of species diversity developed by Shannon; Balushkina; Woodiwiss; Parele; Toderash; Goodnight and Whitley; and Carr, Hiltunenn, and Wright) from the data on the seasonal dynamics of macrozoobenthos. An ecological and sanitary classification of water quality that was developed for this type of rivers is presented. Indices based on the characteristics of oligochaetes, as well as on the taxonomic composition of communities and characteristics of the most indicative species, are shown to be the best choice for characterization of organic pollution prevailing in the Kotorosl' River basin. 相似文献
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N. F. Elansky I. I. Mokhov I. B. Belikov E. V. Berezina A. S. Elokhov V. A. Ivanov N. V. Pankratova O. V. Postylyakov A. N. Safronov A. I. Skorokhod R. A. Shumskii 《Izvestiya Atmospheric and Oceanic Physics》2011,47(6):672-681
In the summer of 2010, the Moscow megacity during two months was within the zone of action of a blocking anticyclone. The accumulation of pollutants in a closed air mass sharply changed the surface air quality. At the end of July-the first half of August, the extreme situation became even more complicated, because the air from regions of turf and grass fires came into Moscow. According to measurement data of the Moscow IAP RAS station, the maximal hourly mean concentrations of chemically active gases NO, NO2, CO, O3, and SO2 were 175.9, 217.4, 15.8, 134.2, and 15.2 ppb, respectively. For NO2 and CO, these values are largest over the entire decadal period of observations at the station and many times exceed the MPC level (see table). The concentrations of greenhouse gases CO2, CH4, and nonmethane hydrocarbons also sharply increased. Analysis of the variability of gas contents in the surface air and in the atmospheric boundary layer showed a close relation between extreme changes in the atmospheric composition and its vertical stratification. 相似文献
8.
Both space and time variations in the 222Rn concentration in the atmospheric surface layer over continental Russia were analyzed on the basis of data obtained in the
Transcontinental Observations into the Chemistry of the Atmosphere (TROICA) experiments. The measurements were taken from
a mobile laboratory which was part of a passenger train moving along the Trans-Siberian Railway from Moscow to Vladivostok.
The factors that affect the spatial distribution of both daily and seasonal variations in the concentrations of 222Rn in the surface air were determined: atmospheric vertical stability, geological features of the area under study, and atmospheric
precipitation. The influence of temperature inversions on the accumulation of 222Rn in the atmospheric surface layer was analyzed. The fluxes of 222Rn from the soil into the atmosphere were estimated for different regions of Russia. 相似文献
9.
N. M. Kalinkina N. A. Berezina A. I. Sidorova N. A. Belkina A. K. Morozov 《Water Resources》2013,40(6):657-666
The results of bioassay and physicochemical analysis of bottom sediments from large water bodies in Northwestern Russia are presented. The water bodies under consideration include Lake Onega, Vygozerskoe Reservoir, and freshwater part of the Neva Estuary (the Eastern Gulf of Finland), which are locally subject to eutrophication and toxic pollution. The potential toxicity of bottom sediments, evaluated by the survival rate of two crustacean species (Gmelinoides fasciatus and Ceriodaphnia affinis) in 7-day tests, varied from high to low values, characterizing 5 quality classes: high, good, moderate, poor, and heavy, with appropriate degrees of toxic pollution from no to very high pollution. Bad zones were identified in the Kondopoga and Petrozavodsk bays of Onega Lake, the northern and southern parts of the Vygozerskoe Reservoir, and the southern part of the Neva Bay near the dam. Bottom sediments were found to have high quality in the open central areas of Lake Onega and the Vygozerskoe Reservoir and in the western part of Neva Estuary. 相似文献
10.
Berezina E. V. Moiseenko K. B. Skorokhod A. I. Elansky N. F. Belikov I. B. 《Doklady Earth Sciences》2017,474(1):599-603
This paper reports proton mass spectrometry data on aromatic volatile organic compounds (VOCs) (benzene, toluene, phenol, styrene, xylene, and propylbenzene) obtained in different Russian regions along the Trans-Siberian Railway from Moscow to Vladivostok, based on expedition data retrieved using the TRO-ICA-12 mobile laboratory in the summer of 2008. The contribution of aromatic VOCs to ozone formation in the cities and regions along the measurement route has been estimated quantitatively. The greatest contribution of aromatic VOCs to ozone formation is characteristic of large cities along the Trans-Siberian Railway (up to 7.5 ppbv O3) specified by the highest concentrations of aromatic VOCs (1–1.7 ppbv) and nitrogen oxides (>20 ppbv). The results obtained are indicative of a considerable contribution (30–50%) of anthropogenic emissions of VOCs to photochemical ozone generation in the large cities along the Trans-Siberian Railway in hot and dry weather against the background of a powerful natural factor such as isoprene emissions controlling the regional balance of ground-level ozone in warm seasons.
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