共查询到20条相似文献，搜索用时 31 毫秒
1.
Multidisciplinary studies carried out in 2007–2008 revealed the features of concentration dynamics of biogenic and organic substances, bacterio- and phytoplankton, and chlorophyll in different reaches of the Enisei River. By the development state of bacterio- and phytoplankton, saprobity index, total primary production g O2/(m2 day), and self-purification index, the water refers to the third quality class (satisfactorily clean), β-mesosaprobic. The Enisei refers to the oligotrophic type upstream of the Angara mouth and to the mesotrophic type downstream of it. 相似文献
2.
I. I. Rudneva E. B. Mel’nikova N. S. Kuz’minova S. O. Omel’chenko I. N. Zaevskaya G. V. Simchuk 《Water Resources》2008,35(4):483-489
Data on the effect of physiological, ecological, and anthropogenic factors on the concentration of nitrosamines in the tissues of bottom-dwelling fish—Scorpaena porcus L. and Mesogobius batrachocephalus Pallas—inhabiting two Black Sea bays with different anthropogenic load are presented. Seasonal dynamics in the concentration of nitrosamines in fish tissues, manifesting itself in its decrease in summer and increase in autumn is revealed. Problems of the environmental risk resulting from the excessive concentration of nitrogen compounds in the marine environment are discussed. 相似文献
3.
L. A. Rukhovets G. P. Astrakhantsev T. R. Minina N. A. Petrova V. N. Poloskov 《Water Resources》2006,33(3):338-352
The effect of potential climate changes on the ecosystem of Lake Ladoga at different levels of anthropogenic load is studied using mathematical models. The Lake Ladoga year-round circulation corresponding to potential climate changes in the lake catchment area is reproduced. The year-round regime of functioning of the lake ecosystem is reproduced using ecosystem models. The potential changes in the lake ecosystem due to changes in the phosphorus load within the limits observed in 1961–1983 are found to be more essential than those due to prognostic changes in climate. 相似文献
4.
E. V. Shchetinina V. V. Maksimov O. V. Kraikivskaya E. A. Maksimova 《Water Resources》2013,40(6):649-656
Results of many-year (1990–2009) microbiological studies of waters in different parts of Southern Baikal subject to different anthropogenic load are presented. Long-term observation series made it possible to establish tendencies in variations of the structure and functional activity of microbiocenoses as the result of natural evolution and anthropogenic impact. The obtained microbiological data characterizes water quality and the level of technogenic disturbances near Baikal Pulp-and-Paper Mill. Water quality assessment by sanitary-bacteriological characteristics suggests that the water area near the discharge site of effluents from Baikal PPM chronically experiences bacterial pollution. No significant changes in the technogenic stress on Southern Baikal ecosystem have taken place since the 1990s. 相似文献
5.
Transport and accumulation of non-cohesive and suspended load in Klaipeda Strait are analyzed. The budget of non-cohesive and suspended load is calculated for the Klaipeda Seaport area under different hydrological conditions. A method is proposed for the forecasting of sedimentation dynamics under anthropogenic changes in the hydrological and morphometric characteristics of the strait caused by the expansion of the Klaipeda Seaport. 相似文献
6.
I. A. Nemirovskaya 《Water Resources》2009,36(1):64-75
Aliphatic and polycyclic aromatic hydrocarbons were studied in water, filtration and separation particulate matter, seston, and bottom sediments with the aim to determine their concentrations and origin and compare them with the concentrations of lipids and Corg (August 2006). The effect of anthropogenic hydrocarbons was identified mostly in the Northern Dvina mouth area and in the apex of Dvina Bay. In other parts of the sea, natural compounds dominate in all examined objects, since anthropogenic hydrocarbon cannot pass through the Northern Dvina-the White Sea geochemical barrier. The low temperatures in the high-latitude water areas are shown not to reduce the rate of diagenetic processes in the sedimentary strata. 相似文献
7.
The main results obtained by processing satellite photographs of the delta and the shallow offshore mouth area of the Volga made from 1975 to 1997. The study includes electronic treatment of the photographs, zoning of the delta and shallow offshore mouth area, and the evaluation of their main quantitative characteristics. Space and time variations in the boundaries of zones, main landscape components, and the hydrological characteristics (higher aquatic plants, currents, water flow, sediments, etc.). The environmental state of the identified zones and the role of anthropogenic load are estimated. 相似文献
8.
The regularities of surge-induced water level variations in the Danube mouth are considered. The recurrence of level rises and drops in the near-shore mouth zone is evaluated. The regularities of the propagation of surge-induced level variations into the delta and over the near-delta reach of the Danube are established. The magnitude of positive and negative surges in the delta and the extent of their propagation are shown to depend on the surge phenomena in the offshore zone and the Danube water discharge.Translated from Vodnye Resursy, Vol. 32, No. 1, 2005, pp. 35–47.Original Russian Text Copyright © 2005 by Isupova, Mikhailov, Morozov. 相似文献
9.
The influence of the Po River discharge on phytoplankton bloom dynamics along the coastline of Pesaro (Italy) in the Adriatic Sea 总被引：1，自引：0，他引：1
In recent years, eutrophic phenomena have frequently been reported in the Italian coastal waters of the northern Adriatic Sea. The aim of the present study was to determine that the phytoplankton blooms occurring along the Italian coastline in the area of Pesaro are caused by the Po River waters. In fact between October and December 2000 the nutrient load flushed into the sea from local rivers is not significant (phosphorus 10 tons and nitrogen 110 tons), instead N and P load from the Po River are: 650 and 8969 tons. The bloom episodes occurred during this period, at which time hypoxia developed on the sea bottom. The phytoplankton cell concentrations were 40.0 x 10(6) cells L(-1), and a significant presence of diatoms was observed. This issue is important in analysing the anthropogenic disturbances and environmental changes. The eutrophic seawater conditions were also analysed using the eutrophic index. 相似文献
10.
Morpho-physiological and biochemical parameters were determined in Scorpion fish Scorpaena porcus L. from two bays in the area of Sevastopol, which experience a high anthropogenic load. The effect of natural and anthropogenic factors on the size, weight, and age composition, as well as on the sex ratio of the fish from both populations, was studied. The relationships between the concentrations of chlororganic substances in the water of the bays, their accumulation in the liver and gonads of the fish, the activity of antioxidant enzymes in the blood, and the fractional composition of serum proteins were determined. A possibility for the use of the Scorpion fish as a indicator species for the biomonitoring and assessment of the environmental conditions in the coastal waters of the Black Sea was considered.Translated from Vodnye Resursy, Vol. 32, No. 2, 2005, pp. 238–246.Original Russian Text Copyright © 2005 by Rudneva, Shevchenko, Zalevskaya, Zherko. 相似文献
11.
Water Resources - Changes in the runoff of rivers flowing into the Arctic Ocean caused by climate changes and increasing anthropogenic load lead to foreseeable transformations of hydrological... 相似文献
12.
Two types of plots characterizing the undisturbed structure of the biotopic spectrum of diatom algae are recognized. The first of them has a hyperbolic form and the second is a sigmoid curve (normal distribution). It was shown that, under adverse external impact, both types of plots change their shape and the extent of their distortion reflects the general level of anthropogenic load on this water body or its part. The proposed method of graphical comparison was developed for lakes of Kola Peninsula. Later it was successfully used in the biomonitoring of watercourses of the Volga–Akhtuba interfluve area (Astrakhan Province) and in paleoenvironmental reconstruction for Galichskoe Lake (Kostroma Province). 相似文献
13.
Regularities of the formation of biogenic elements flow and water quality in the Istra River (downstream of the Istrinskoye Reservoir) and its tributaries are revealed. Temporal variability in water quality parameters is shown to be closely related to fluctuations in the river water abundance, whereas spatial variability is determined by different intensity of anthropogenic load on river watersheds. It was found that the mean annual (for the period of 1991–1995) concentrations of nitrogen and phosphorus mineral compounds do not always meet the requirements of drinking water supply. A method of estimating the environmental state of the main river, taking into account biogenic elements input from its basin is suggested. 相似文献
14.
V. N. Egorov S. B. Gulin L. V. Malakhova N. Yu. Mirzoeva V. N. Popovichev N. N. Tereshchenko G. E. Lazorenko O. V. Plotitsina T. V. Malakhova V. Yu. Proskurnin I. G. Sidorov A. P. Stetsyuk L. V. Gulina 《Water Resources》2018,45(2):222-230
Sevastopol Bay is used as an example for the development of criteria for rating anthropogenic impact by elimination fluxes from the water area of post-Chernobyl (90Sr, 137Cs, 239,240Pu) and natural (210Pо) radionuclides, as well as mercury and organochlorine compounds. The differentiation of the bay water area into zones with different biogeochemical conditions and the balance approach to interpreting field observation data were used to assess the conditioning capacity of Sevastopol Bay ecosystem for conservative radioactive and chemical substances by elimination fluxes of pollutants into aqueous depot, which is the open part of the Black Sea and into the geological depot, i.e., its bottom sediment stratum. 相似文献
15.
N. I. Alekseevskii S. O. Grinevskii P. V. Efremov M. B. Zaslavskaya I. L. Grigor'eva 《Water Resources》2003,30(5):540-549
Data from surveying small rivers in Moscow and Tver oblasts are used to assess the anthropogenic load on their watersheds. Expert estimates of the effect of such load onto the state of surface water are made. Integral characteristics and similarity criteria of the hydroecological conditions of small rivers are substantiated. 相似文献
16.
The dynamics of anthropogenic activity and anthropogenic sources of nutrients in the Republic of Bashkortostan have been analyzed. Statistical analysis of many-year data of hydrochemical monitoring have been used to establish the year-to-year and annual regularities in the variations of N compound concentrations in watercourses. Maps of the mean annual N concentration in its forms (ammonium, nitrites, and nitrates) have been constructed. The fitness of river water to different types of water use have been assessed. Probability distributions of the concentrations of hydrochemical components have been constructed for different phases of stream water regimes. The exceedance probabilities have been evaluated for MAC values of N compounds in watercourses. 相似文献
17.
With the help of a stationary balance model, the mean annual amounts of P retained in the chain of the Volga water reservoirs are sequentially calculated. It is found that with the current anthropogenic load, the Volga River regulation leads to a twofold decrease in the P runoff into the Caspian Sea. 相似文献
18.
D. B. Denisov 《Water Resources》2007,34(6):682-692
Paleoecological studies of small water bodies were carried out in a model subarctic lake-river system. The degree of transformations of aquatic ecosystems under a set of anthropogenic factors is shown to vary depending on the load and individual features of water bodies. Data on the state of aquatic ecosystems before the industrial development of the region are collected. The species composition of diatom algae and their ecological characteristics are examined. 相似文献
19.
The distribution of reduced sulfuric compounds in the surface layer of bottom deposits in the Northern Dvina mouth was examined. The natural biogeochemical processes and anthropogenic pollution are found to cause the formation and accumulation of reduced sulfuric compounds (mostly pyrite and organic forms) in bottom deposits. The concentration of individual forms of sulfur and its total concentration are found to vary widely from year to year. The most intense accumulation of the total reduced sulfur is recorded near the wastewater discharge sites of pulp and paper mills. 相似文献
20.
Surface seawater samples were collected in the Irish Sea and Liverpool Bay area from the R.V. Prince Madog during the period of 25-31 of March 2006. VOCs were purged with nitrogen, pre-concentrated on a SPME fibre and analysed immediately on a GC-MS. Target compounds quantified were halogenated (0.2-1400 ng L(-1)), BTEXs and mono-aromatics (1.5-2900 ng L(-1)), aliphatic hydrocarbons and others (0.6-15,800 ng L(-1)). Day and night sampling was performed at a single station and suggested that factors such as sunlight and tide affect the presence of many of these compounds. Sample variability was high due to the variable weather conditions at the station. Poor correlations were found between marine phytopigments and selected VOCs. Principal component analysis (PCA) analysis showed that chlorinated compounds such as 1,2-dichloroethane, 1,1,1-trichloroethane, trichloroethene, tetrachloroethene and carbon tetrachloride, predominantly from anthropogenic sources, originated from the River Mersey. Other brominated and iodinated compounds quantified were more likely to be from biogenic sources including novel marine compounds such as 2-chloropropane, 1-bromoethane and 1-chlorobutane. 相似文献