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1.
S. L. Gorin 《Water Resources》2013,40(1):1-15
The results of many-year field studies are used to discuss the issues of formation of the hydrological regime and the morphological pattern of the estuary of the Bol’shoi Vilyui R., belonging to the subtype of lagoon-lacustrine estuaries. A vast body of factual data, which characterize the estuary and the processes taking place in it, as well as the natural conditions under which it exists. 相似文献
2.
We provide new evidence that bears on the geological structure, history of evolution, and structural setting for the Bol’shoi Semyachik Volcanic Massif in Kamchatka. The new Ar-Ar results for dating of volcanic rocks allowed significant advances in updating the stratigraphy and history of the evolution of the area of study. We discuss the distribution of centers of volcanic and hydrothermal activity in the Bol’shoi Semyachik Massif area. The distribution suggests that the volcanism in the area is progressively migrating southeastward. It is shown that all thermal occurrences, such as sets of steam jets, thermal springs, and heated patches (evidence of present-day activity), are also displaced into the southeastern part of the massif. It was concluded that these patterns are not accidental, but are controlled by dipping magma-conducting and fluid-conducting faults that bound a major basement low on the southeast. The low had been identified earlier from geophysical observations. The dip gives the result that the magma and fluids rise to the surface and simultaneously deviate eastward and southeastward, where the youngest occurrences of volcanic activity and present-day thermal features are found today. 相似文献
3.
The results of studying the hydrological regime of Lake Bol’shoi Tambukan and its catchement are discussed; the data reveal higher total evaporation from forest plantings in comparison with evaporation from other land areas of the catchment. A close relationship was shown to exist between the lake water level and humidity factor of the surrounding area; it was most contrasting during the four-year period when the water level rose by 2.5 m and caused critical environmental situation in the water body. Over the period of 33 years, water supply to the lake ruled out its natural sterilization. The need to regulate the lateral inflow into the lake with regard to the volume of man-made water supply was shown. 相似文献
4.
Groundwater chemistry in the northwestern Bol’shekhetskaya Megasyneclise is considered, and the predominance of inversion hydrogeochemical zonality is identified. The analysis of the hydrogeochemistry and genetic coefficients enabled the tentative identification of infiltrogenic, sedimentogenic, lithogenic, and condensatogenic types of waters. The implemented paleohydrogeochemical reconstructions confirmed the predominance in the cross-section of ancient infiltrogenic and slightly saline sedimentogenic water at all development stages of the sedimentary basin. 相似文献
5.
This paper reports the results of magnetotelluric sounding (MTS) in the area where the Bol’she-Bannyi hydrothermal springs are discharged. The MTS curves were inverted on the assumption of a twodimensional inhomogeneous model using longitudinal and transverse curves of apparent resistivity. It was found that the geoelectric section contains a nearly vertical anomaly of high electrical conductivity at depths of 5.5–8 km, which is the signature of a deep-seated fault. The resulting geoelectric section for the upper crust and data from regional magnetotelluric soundings were used as a basis for developing a conceptual deep model of the Bol’she-Bannyi hydrothermal system. We quote an approximate estimate of rock porosity. According to the model, deep fluids come from a crustal layer into the subvertical deep-seated fault then penetrate via fissures into the sedimentary–volcanogenic cover, and finally arrive at the ground surface in zones of high rock permeability. We provide a recommendation for drilling a deep well in order to determine the potential of the Bol’she-Bannyi hydrothermal field. 相似文献
6.
V. V. Shcherbakova G. V. Zhidkov V. P. Shcherbakov 《Izvestiya Physics of the Solid Earth》2008,44(10):816-821
A large volume of data on the paleointensity H an obtained by A.S. Bol’shakov and G.M. Solodovnikov is ignored in modern reconstructions because the authors did not indicate whether they used the check-point procedure for the detection of chemical alterations in rocks associated with determination of H an. The paper presents new values of H an determined by the Thellier-Coe method with the use of the checkpoint procedure from samples of the Armenian collection of Cretaceous rocks used in published studies of Bol’shakov and Solodovnikov. The new results are close to the published ones and point to a small value of the geomagnetic field in the Cretaceous, thereby corroborating Bol’shakov-Solodovnikov’s hypothesis on a low paleofield in the Mesozoic. Our study of samples of the collection studied confirms the reliability of Bol’shakov-Solodovnikov’s determinations of H an. 相似文献
7.
Water Resources - The results of long-term field studies are used to consider in detail the issues of hydrological regime formation in a lagoon–channel estuary of the Bol’shaya R. in... 相似文献
8.
Dr. M. C. Kavanaugh Dr. U. Zimmermann Mrs. A. Vagenknecht Dipl.-Ing. Eidg. Anstalt für Wasserversorgung. Abwasserreinigung und Gew?sserschutz CH- Dübendorf Switzerland 《Aquatic Sciences - Research Across Boundaries》1977,39(1):86-98
Use of a Zeiss Micro-Videomat electronic image analyzer for routine measurements of size distributions of particles found in natural waters greater than 0.3 μm has been investigated. Staining of particles with a solution of Gentiana-violet eliminated the multiple-count problem which has frustrated earlier attempts to use image analyzers for quantitative phytoplankton work. Concentration of samples from the lake water column was successfully achieved with an impact centrifuge. Losses of inorganic particles indicate that the centrifuge method must be evaluated on an individual case basis. Precision and accuracy of the Zeiss Micro-Videomat using either sedimentation (Utermöhl) or centrifugation for sample concentration were satisfactory for particles larger than 1 μm. The system appears promising for routine surveillance of raw water quality at water treatment plants, and performance of unit processes used for particulate removal, as well as for specific investigations of ecological phenomena in natural waters. 相似文献
9.
A three-level scheme is proposed for the identification of sources of fresh and old petroleum pollution of water bodies and streams, including an optimal complex of simple, available, and highly effective physicochemical techniques, criteria, and sample processing methods ensuring the reliability of conclusions derived from them. The efficiency of application of the proposed methods is illustrated in several water bodies and streams (the Bol’shaya Krepkaya, Tuzlov, Chitinka, and other rivers), which have experienced oil pollution. 相似文献
10.
This article is the first to give morphometric and bathymetric relationships for Bol’shoe Yashaltinskoe Lake, derived by processing expedition data. A bathymetric map of the lake is constructed. A method is proposed for modeling lake water balance and water salinity based on geographic analogy and an algorithm for constructing a stochastic vector autoregression process. Realizations of the simulated series of lake water balance components and water salinity variations over 1000 years with a monthly step are constructed. 相似文献
11.
An area where fresh volcanic ash has fallen was found to have concentrations of Th and U that exceed the background values by factors of 270 and 32, respectively, for natural waters and by factors of 35 and 6 for plants. The soils and bottom deposits were not enriched in Th and U after a single ashfall; however the Th/U ratio decreased in these natural media relative to the background values, indicating a genetic affinity with young ashes where the concentration of highly mobile (relative to thorium) uranium is higher compared with older ashes. For areas far from active ashfalls, where the soils were formed on acid ash, we found higher background concentrations of Th and U in soils, surface waters, and bottom deposits, as well as higher gamma-ray background values above the Earth’s surface relative to the areas where the soils were formed on basic and intermediate ashes. This research resulted in the identification of two radioecological provinces in Kamchatka, viz., a Northern and a Southern province. 相似文献
12.
Catherine D. Clark Warren J. De Bruyn Charlotte M. Hirsch Paige Aiona 《Marine pollution bulletin》2010,60(12):2284-2288
Hydrogen peroxide is photochemically produced in natural waters. It has been implicated in the oxidative-induced mortality of fecal indicator bacteria (FIB), a microbial water quality measure. To assess levels and cycling of peroxide in beach waters monitored for FIB, diel studies were carried out in surf zone waters in July 2009 at Crystal Cove State Beach, Southern California, USA. Maximum concentrations of 160–200 nM were obtained within 1 h of solar noon. Levels dropped at night to 20–40 nM, consistent with photochemical production from sunlight. Day-time production and night-time dark loss rates averaged 16 ± 3 nM h−1 and 12 ± 4 nM h−1 respectively. Apparent quantum yields averaged 0.07 ± 0.02. Production was largely dominated by sunlight, with some dependence on chromophoric dissolved organic matter (CDOM) levels in waters with high absorption coefficients. Peroxide levels measured here are sufficient to cause oxidative-stress-induced mortality of bacteria, affect FIB diel cycling and impact microbial water quality in marine bathing waters. 相似文献
13.
Strontium isotope identification of water mixing and recharge sources in a river system (Oder River,central Europe): A quantitative approach 
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下载免费PDF全文 Mateusz Zieliński Jolanta Dopieralska Zdzislaw Belka Aleksandra Walczak Marcin Siepak Michał Jakubowicz 《水文研究》2018,32(16):2597-2611
This study uses Sr isotope composition (87Sr/86Sr) and Sr content of waters of the Oder, one of the largest rivers in central Europe, to fingerprint natural and anthropogenic contributions to its Sr budget and to evaluate water mixing processes in its hydrological system. It also demonstrates a simple method of quantifying natural and anthropogenic Sr inputs in the watershed. The method has potential for environmental and archaeological research because past Sr geochemistry of river water can easily be reconstructed. For the first time, a catchment‐scale impact of anthropogenic sources on the Sr budget of a middle‐size river is shown in a quantitative way. The water of the Oder is characterized by a relatively uniform Sr isotope composition, from 0.7100 to 0.7108, contrasting with strong variations in Sr concentration, from 0.25 to 1.27 mg/L. There is a general seasonal trend in variability, with waters becoming more radiogenic and dilute with respect to the Sr in the spring time. This Sr systematics differs significantly from the Sr budgets of the majority of the Oder tributaries that exhibit more radiogenic composition and systematically lower Sr concentrations. A mixing scenario in the Oder involves Sr contribution from four principal water sources: (a) shallow ground waters with Sr derived from near‐surface weathering of silicates, (b) moderately radiogenic mine waters from the Upper Silesian Coal Basin, (c) unradiogenic mine waters from the Permian sequence of the copper district, and (d) unradiogenic ground waters from shallow‐seated Palaeogene, Neogene, and Mesozoic aquifers. The Sr budget of the Oder is primarily controlled by inputs of dissolved Sr from anthropogenic sources, which overprint the natural background, controlled by geology. Thus, about 47.5% of Sr originates from agriculture, industrial, and municipal additions, 31.5% from mine water inputs, and only 21% from natural sources, that is, rock weathering and atmospheric precipitation. Reconstruction of the past Sr chemistry of the Oder reveals that its present‐day Sr isotope composition is temporary and significantly different from that of the preindustrial times. 相似文献
14.
On rocky shores, sewage discharges can modify natural distribution patterns of sessile organisms. The impact of sewage on shallow hard substrate assemblages has been assessed along SW Apulian coast (Ionian Sea, Italy), providing a framework to evaluate the benefits of future sewage displacement to deeper waters. Four locations (three controls and one putatively impacted) were selected and three sites were chosen at each location. Each site was sampled by 10 replicate photographic records. Univariate analyses revealed that the outfall did not affect the spatial distribution of number of taxa, total cover and abundance of some dominant taxa (mostly algae, sponges and bryozoans). The outfall negatively influenced the natural distribution pattern of filamentous green algae, whilst some algae (i.e. Gelidiales and Colpomenia sinuosa) were exclusively present at the impacted location. Multivariate analyses revealed that the outfall heavily modified the natural pattern of variability in the structure of the assemblage. 相似文献
15.
Assessing the impacts of climate change on water quantity and quality modelling in small Slovenian Mediterranean catchment – lesson for policy and decision makers 下载免费PDF全文
下载免费PDF全文 The study aims to address the long‐term impacts of six different downscaled Regional Climate Models (RCM) climate models on the quantity (river flow) and quality (sediment load, total nitrogen load and total phosphorus load) state of surface waters in the river Reka catchment, in the northern Mediterranean. Mediterranean areas are – due to high population density, favourable natural conditions for agriculture, limited water resources, diverse ecosystems biodiversity and expected climate change impacts – a global hotspot in climate research. Additionally, the study area lies on the border with the alpine climate zone, with a strong orographic effect on weather patterns. The location, and a wide range of studied parameters, provides an interesting insight into how various emerging climate change models may impact the status of surface waters and procedures for the governance of water resources. The study contributes to the knowledge and understanding of the climate change impact on the local catchment level, using the ensemble of the RCMs. It opens discussion about the impact of RCM selection on modelling climate changes with catchment models like Soil and Water Assessment Tool. This article also questions the usability of the results for the policy and decision makers in relation to the implementation of the results into short or long‐term water strategies or water/river management plans. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
16.
Adverse impacts on the health of some fish populations, such as skewed sex distributions, have been noted in surface waters and in laboratory experiments with relatively low concentrations (above 25 ng/L) of natural estrogen (17 beta-estradiol--E2). Sources of E2 to surface and ground waters can include avian, human, and mammalian waste products. The Ozark Plateau Aquifer (OPA) is a karstic basin that receives a significant portion of its water through losing reaches of rivers. Thus, there is a direct connection between surface water and ground water. The OPA was targeted for an E2 study to assess the potential for adverse health effects to aquatic organisms living in the system. Eight springs, which drain the aquifer, were sampled quarterly. The concentrations of E2 in the OPA ranged from 13 to 80 ng/L. For any one sampling event, the concentrations of E2 at the spring waters were statistically similar; however, the concentrations of E2 at all springs varied throughout the year. At Maramec Spring, one of the larger springs, the E2 concentration, was correlated with discharge. Based on the correlation between discharge and E2 concentration, aquatic organisms living in the plateau or in its discharged waters, including the threatened southern cavefish T. subterraneus, are exposed to concentration of E2 above 25 ng/L approximately 60% of the time. This implies that organisms living in karst basins throughout the OPA are likely exposed to E2 concentrations that may adversely impact their reproductive success for a significant portion of each year. 相似文献
17.
Cu concentrations in surface (river and lake) and subsurface waters are determined. The geographic pattern of Cu distribution in natural water is identified. This pattern is controlled by the difference between its concentrations in drained rocks and soils and the geochemical redox conditions of its migration. Territories with low, medium, and elevated Cu concentrations in natural waters are identified. The concentrations of Cu in natural waters of the region are found to be generally lower than the Clarke values. 相似文献
18.
The space and time variations in the acidity and composition of the natural water in forest-covered water-divide areas in northern taiga are considered. The initial stages of natural water quality formation are analyzed. The external (climate and anthropogenic) and internal (biogeocenotic) factors governing the formation of natural water quality are characterized. The most pronounced transformations of natural waters are shown to take place in the snowless period. The contribution of tree species to the formation of the environmental characteristics and the anisotropy of natural waters in the forest is characterized. The natural regularities in soil water composition within selected profiles are shown to persist to the point of destruction of forest biocenoses. It is shown that the commonly accepted notions of the natural water quality formation in forest water divide areas need to be revised with allowance made to their spatial structure and time variations. The soil waters under tree crowns are shown to give the best data for early assessing the conditions of forest biocenoses in spring and autumn. 相似文献
19.
C.L. So 《Marine pollution bulletin》1979,10(11):334-337
Examination of mercury-water interactions in the estuarine environment reveals that, while locally mercury concentration in estuarine waters may reflect external influence on the estuarine system, the interactions of the heavy metal with soluble and insoluble water components greatly influence the transport of the metal and its impact on the biota in natural waters. In connection with transformation of mercury in aquatic ecosystems, the role played by methylation in spatial and temporal mobilization of mercury is viewed in wider perspective. This throws light on metal concentration and dispersion and the need for monitoring them in any realistic environmental management design. 相似文献
20.
P. A. Lozovik 《Water Resources》2013,40(6):631-639
A classification of surface waters of humid zone by its humus content, alkalinity, and trophic status has been developed basing on the acid-base equilibrium of those waters, governed by two systems: humus and carbonate, which enabled the geochemical classes of water to be established more objectively than by expert systems. An integrated estimate of natural water quality is given with the use of quality points by individual characteristics. For water bodies subject to anthropogenic impact, the degree of their pollution is given in accordance with water pollution index, which is calculated by the main standardized components, taking into account their geochemical background level and the values of MAC for water bodies used for fishery. 相似文献