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1.
The specific features of freshwater bodies are shown to facilitate the accumulation of oil products in bottom deposits. The oil product components are found to be represented by hydrocarbons and tars. The latter component can account for more than 50% of their total. The extent of bottom deposits pollution by oil products is assessed for a number of freshwater bodies in Russia.  相似文献   
2.
The spatial distribution of the concentrations of heavy metals Cd, Pb, Zn and Cu were studied for contaminated wetlands located by industrial centres and villages influenced by anthropogenic contamination in the Russian Arctic. For comparison, non-contaminated wetlands were also studied in neighbouring areas. Samples were collected during the period 1977–1994 and included: (a) water, (b) particulate matter, (c) bottom sediments, (d) hydric soils and (e) hummock bog peat and polygonal bog peat. For impacted wetlands, the observed ranges for the concentrations of Cd, Pb, Zn, and Cu in water were 0.12–0.8, 0.9–2.5, 2.4–15 and 16–34 μg l−1, respectively. For (b)- (e) the corresponding values were [1.2–5.4; 24–37; 120–320; 80–116]; [6.4–17; 34–59; 240–570; 115–280]; [10–32; 57–78; 315–480; 87–350] and [5.1–53; 51–150; 125–520; 80–440] mg/kg, dry wt, respectively. The metal concentrations were up to 1000 times higher than background levels determined for non-contaminated wetlands in the Russian Arctic. The contaminants appear to be a direct result of localized anthropogenic activity, arising primarily from geoprospecting, the oil and coal industry, and domestic waste.  相似文献   
3.
The toxicity of river water in the Lower Don basin was studied using biotesting with different biological objects. Water taken from most examined reaches of the Don and its tributaries was shown to exert toxic effect on crustaceans, algae, protozoa, and Rotifera.  相似文献   
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In order to study the effect of pollutants on intrabasin processes, a series of nature experiments has been made in natural model ecosystems (mesocosms). The intensity of photosynthetic production and organic matter destruction have been studied as generalized thermodynamical parameters of the state of the ecosystem. On the basis of the ratio between destruction and overall production, dynamical phase patterns have been built. Analysis has shown that the dynamics of the state of the ecosystem described by these parameters corresponds to general regularities of the evolution of the state of dissipative systems. Consequently, the destruction-to-production ratio can be considered as a thermodynamic criterion for assessment in the evolution of the state of water ecosystems. On the basis of this criterion, and with the help of the approach proposed, methods of ecological load normalization can be elaborated.  相似文献   
6.
Considered is the dynamics of pesticide content in surface water bodies of the Russian Federation during the long-term period. Demonstrated are the key directions of improving and optimizing observations of pesticide content in surface waters. Proposed is a priority list of pesticides recommended to be determined in water bodies of the country based on the known criteria of estimating the potential hazard of pesticides.  相似文献   
7.
The results of calculation and analysis of the inflow of dissolved chemical substances to the estuarine area of the Northern Dvina River are considered. Based on the long-term regime hydrochemical information of the State Service of Observation and Monitoring of the Natural Environmental State, the anthropogenic load of dissolved chemical substances on the estuarine area and on the estuarine coastal water is estimated per inflow volumes. The extent of the water environment pollution of the near-delta part of the Northern Dvina River and its delta is estimated. The distribution of pollutant inflow among arms and channels in delta is under consideration.  相似文献   
8.
Many-year variations of water pollution and the state of more than two hundred of rivers (or their segments) in different latitudinal zones in European Russia are estimated. In accordance with latitudinal zonality, space and time trends in variations of water quality and the state of rivers are identified. By the level of water pollution, most river ecosystems (or their segments) were classified as polluted and very polluted, very polluted and dirty, dirty and very dirty. A tendency toward water quality improvement could be seen in the recent decade. More than 50% of the examined river ecosystems are at the transitional state of passing from natural (and/or equilibrium) to crisis state.  相似文献   
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Data of long-term observations of Roshydromet and the studies of the authors’ studies of hydrochemical, hydrobiological, and bioassaying characteristics and appropriate publications in the areas of megalopolises—the cities of Rostov-on-Don and Novosibirsk are analyzed. Similar and distinctive characteristics of water quality by these ecological-toxicological characteristics are identified; trends in the long-term year-to-year variations in water quality are established, criteria and characteristics reflecting the effect of cities on water bodies in their territory are determined. The identity of some chemical-toxicological criteria and the characteristics of the influence of cities in southern Russia and Siberia on water bodies suggest that they can also be used in urban area in other regions. The Lower Don is used as an example to show that water pollution by metals is mostly due to wastewater discharge, while water pollution by petroleum products and sulfates has no direct relation to that.  相似文献   
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