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In 1983, the Preparatory Commission for the International Sea-Bed Authority and the International Tribunal for the Law of the Sea appointed its officers, decided upon its structure and adopted a programme of work. In July of the previous year, the US Government announced that it would not sign the Convention on the Law of the Sea and thus would not participate in the deliberations of the Preparatory Commission. As part of the Texts adopted, Resolution II establishes a scheme for the Protection of Pioneer investment pending the entry into force of the Convention. This scheme is predicated on the philosphy embodied in the Convention in respect of the establishment of a resource policy for the development of sea-bed mineral resources and takes into account its basic component, the limitation of production. This article investigates the impact of future sea-bed mineral development on the affected economies of developing land-based producer states. It also reviews the mechanisms to be utilized to mitigate against possible adverse impacts and attempts to assess the extent to which these resources may be exploited in the medium term.  相似文献   
3.
Investigations on the influence of pressure on the activity of alkaline phosphatase of some marine invertebrates from the Baltic Sea were carried out at temperatures between 5° and 55°C. The results obtained indicate that the influence of pressure on alkaline phosphatase activity is modified by temperature. At low temperatures, pressure has a decreasing effect on enzyme activity, while it has an increasing effect at higher temperatures. The gill homogenates of the relatively pressure-resistent bivalves Cyprina islandica and Mytilus edulis show a lower decrease of activity under pressure at low temperatures than the gill-homogenate of Carcinus maenas and a purified enzyme preparation of a homoiothermal animal.  相似文献   
4.
Previous discharges of radioactivity from the Mayak Production Association plant in the Urals have resulted in considerable radionuclide contamination of the Techa River, and consequent high radiation doses during the late 1940s and 1950s to residents of villages along the Techa river. The most contaminated villages close to the site were evacuated in the period 1954-1962. The objective of this recent study was to conduct a preliminary assessment of the current radioactive contamination of soil, vegetation and foodstuffs in the two remaining villages closest to the Mayak site, Muslyumovo and Brodokalmak. The highest contamination levels in soil were found in the floodplain at 5.5 MBq m(-2) for 137Cs and 1.0 MBq m(-2) for 90Sr. Radionuclide contamination in soil of the villages was much lower, but exceeded that expected from global fallout. Data from 1207 measurements of 137Cs in milk and 1180 for 90Sr in milk for the period 1992-1999 were collated. There was no change with time in the 90Sr or 137Cs activity concentration in milk over the measured period. There were significantly higher 137Cs activity concentrations in milk sampled during the housed winter period in Muslyumovo compared with the grazing summer period, but compared to that for Brodokalmak or for either settlement for 90Sr. The highest measured activity concentrations in food products of 137Cs and 90Sr were found in river fish, waterfowl, poultry and milk. The measured activity concentrations of 137Cs and 90Sr in some animal products were higher than that expected from soil and vegetation from fields and pasture in the villages (not including the floodplain) confirming that the highly contaminated floodplains are contributing to contamination of some animal products.  相似文献   
5.
Charge characteristics of humic and fulvic acids of a different origin (inshore soils, peat, marine sediments, and soil (lysimetric) waters) were evaluated by means of two alternative methods - colloid titration and potentiometric titration. In order to elucidate possible limitations of the colloid titration as an express method of analysis of low content of humic substances we monitored changes in acid-base properties and charge densities of humic substances with soil depth, fractionation, and origin. We have shown that both factors - strength of acidic groups and molecular weight distribution in humic and fulvic acids - can affect the reliability of colloid titration. Due to deviations from 1:1 stoichiometry in interactions of humic substances with polymeric cationic titrant, the colloid titration can underestimate total acidity (charge density) of humic substances with domination of weak acidic functional groups (pK>6) and high content of the fractions with molecular weight below 1kDa.  相似文献   
6.
Analysis of the evolution, distribution and ecology of marine prosobranchs of the genera Neptunea and Littorina and amphipods of the genera Anisogammarus and Gammarus demonstrates the possibilities of ecological and palacoecological methods in composing evolutionary reconstructions. A comparative study of historical climate changes and of palaeogeography in areas inhabited by certain taxonomic groups, coupled with information on the distribution and ecology of species belonging to these groups, allows us to determine the time and locality of the origin of diverse biogeographical groups of species and to trace the routes of their further distribution, even in those organisms which have no fossil remains. Species dwelling under conditions which correspond historically to the most ancient climate of their dwelling area prove to be more primitive than species dwelling under newly-formed climatic conditions. For instance, subtropical species of the genera under consideration, in the Northwestern parts of the Pacific and Atlantic Oceans, have proved to be more ancient and primitive than species inhabiting the upper boreal Pacific and Atlantic waters and the Arctic Ocean. Therefore, the palaeoecological analysis of the historical development of faunas from different regions of the globe, combined with the application of the morphological principle, can significantly contribute to a more detailed and precise understanding of the processes and trends of evolution which compose the phylogenetic schemes of the taxonomic groups under discussion.  相似文献   
7.
In this paper a compartment model of the highly vulnerable Arctic terrestrial food chain "lichen-reindeer-man" is outlined. Based upon an analysis of measured (137)Cs and (90)Sr contents in lichen and reindeer meat from 1961 up to 2001, site specific model parameters for two regions in north-western Arctic Russia and for Kautokeino municipality in Arctic Norway have been determined. The dynamics of radionuclide activity concentrations in the "lichen-reindeer-man" food chain for all areas was satisfactorily described by a double exponential function with short-term and long-term effective ecological half-lives between 1-2 and 10-12 years, respectively, for both (137)Cs and (90)Sr. Using parameter values derived from the model, life-time internal effective doses due to consumption of reindeer meat by reindeer-breeders after an assumed single pulse deposit of 1 kBq m(-2) of (137)Cs were estimated to be 11.4 mSv (Kola Peninsula), 5 mSv (Nenets Autonomous Area), and 2 mSv (Kautokeino, Norway). Differences in vulnerability to radiocaesium deposition were due to differences in transfer between lichen and reindeer and in diet between the three regions.  相似文献   
8.
Vertical distributions of 137Cs have been determined in vegetation-soil cores obtained from 30 different locations around two underground nuclear explosion sites--"Crystal" (event year - 1974) and "Kraton-3" (event year - 1978) in the Republic of Sakha (Yakutia), Russia. In 2001-2002, background levels of 137Cs surface contamination densities on control forest plots varied from 0.73 to 0.97 kBq m(-2) with an average of 0.84+/-0.10 kBq m(-2) and a median of 0.82 kBq m(-2). 137Cs ground contamination densities at the "Crystal" site ranged from 1.3 to 64 kBq m(-2); the activity gradually decreased with distance from the borehole. For "Kraton-3", residual surface contamination density of radiocaesium varied drastically from 1.7 to 6900 kBq m(-2); maximal 137Cs depositions were found at a "decontaminated" plot. At all forest plots, radiocaesium activity decreased throughout the whole vertical soil profile. Vertical distributions of 137Cs in soil for the majority of the plots sampled (n=18) can be described using a simple exponential function. Despite the fact that more than 20 years have passed since the main fallout events, more than 80% of the total deposited activity was found in the first 5 cm of the vegetation-soil cores from most of the forested landscapes. The low annual temperatures, clay-rich soil type with neutral pH, and presence of thick lichen-moss carpet are the factors which may hinder 137Cs transport down the soil profile.  相似文献   
9.
In 8 intermittently reproducing mollusk species, it was possible to estimate production properties on the basis of the population's size-weight structure. The increase in weight of individuals and the variations in the number of individuals per population allow to calculate the annual growth production of a population from quantitative samples obtained at different seasons. A mathematical model was employed to simulate natural production processes of a population. The computor programme yielded estimates of pure production in the sense of previous authors, and revealed that 4 samples taken in different seasons are sufficient for determining the average annual production with an error of less than 5%. When the average annual growth production is estimated from a single sampling, the best results are received from analysing a population in the middle of the period during which the young appear. Supporting production (quantity of substances formed and retained by a population within 1 year) secures the dynamic numerical balance in a population of a given age structure. Its Ps/B coefficient (Ps: supporting production; B: biomass) changes only insignificantly within 1 year, and is inversely proportional to the maximum age of individuals prevalent in the population. Related species and species with similar size-weight indices have a similar growth rate and approximately similar growth-curve characteristics. The rate of production is related with the species' thermal properties; different biogeographical groups of species attain their maximum productivity in different seasons. Even in certain parts of the same coastal basin (which differ in their temperature regime), production processes of one and the same species may vary. Seasonal fluctuations in productivity are highest in species with short life cycles and in populations subjected to marked environmental changes. Numerical stability is a constant property of populations as long as the hydrobiological environment does not change significantly over the years. Quantitative relationships between supporting production, biomass and growth production may serve as a measure for assessing the degree of the industrial exploitation of a population.  相似文献   
10.
The effect of increased ambient temperature on the vertical, radial, and volume increments of Scots pine (Pinus sylvestris L.) trees has been studied in the zone of thermal impact from a burning petroleum gas flare. Regular age-dependent changes in the pattern of increment dependence on the distance from the flare and ambient temperature have been revealed. The mechanisms of these changes are explained. It is concluded that an increase in ambient temperature by 1.0–1.5° C has a favorable effect on the dynamics of Scots pine growth.  相似文献   
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