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671.
Pesticides that contain a halogen functional group have been destructed by means of detonative combustion. The following compounds were examined: (1) atrazine—2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine—herbicide; (2) bromophos—O,4-bromo-2,5-dichlorophenyl O,O-dimethyl phosphorothioate—insecticide; (3) chloridazon—5-amino-4-chloro-2-phenylopyridazin-3(2H)-one—herbicide; (4) linuron—3-(3,4-dichlorophenyl)-1-metoxy-1-methylurea—herbicide; (5) metoxychlor—1,1,1-trichloro-2,2-bis(4-metoxyphenyl)ethane—insecticide and acaricide; and (6) trichlorfon—dimethyl 2,2,2-trichloro-1-hydroxyethylphosphonate—insecticide. Explosive material has been produced on the basis of ammonium nitrate, which served as an oxidizer while the pesticides were used as fuels. Composition of the explosive was adjusted in such a way as to respect thermodynamic parameters. Detonative decomposition of the mixtures has been carried out in shot-holes pre-drilled in soil. Efficiency of the pesticide decomposition has been examined with gas chromatography in order to determine pesticides residues in the environment. It was found that for some, the amount of pesticides in some compounds in the analyzed samples after decomposition was below the determination threshold of the applied method.  相似文献   
672.
Assessment and economic valuation of services provided by ecosystems to humans has become a crucial phase in environmental management and policy-making. As primary valuation studies are out of the reach of many institutions, secondary valuation or benefit transfer, where the results of previous studies are transferred to the geographical, environmental, social, and economic context of interest, is becoming increasingly common. This has brought to light the importance of environmental valuation databases, which provide reliable valuation data to inform secondary valuation with enough detail to enable the transfer of values across contexts. This paper describes the role of next-generation, intelligent databases (IDBs) in assisting the activity of valuation. Such databases employ artificial intelligence to inform the transfer of values across contexts, enforcing comparability of values and allowing users to generate custom valuation portfolios that synthesize previous studies and provide aggregated value estimates to use as a base for secondary valuation. After a general introduction, we introduce the Ecosystem Services Database, the first IDB for environmental valuation to be made available to the public, describe its functionalities and the lessons learned from its usage, and outline the remaining needs and expected future developments in the field.  相似文献   
673.
674.
Seasonal changes in lipid, glycogen, protein (Nx6.25), and ash content of the meat of Macoma balthica (L.) from five sampling sites in the Gulf of Gdask were studied from 1981 to 1984. Lipid and glycogen were stored mainly during spring and at the beginning of summer. The lipid content of up to 36% of the dry weight observed in populations from the Gulf of Gdask are among the highest values reported for bivalve molluscs. Potential causes of this high value are discussed.  相似文献   
675.
The purpose of this study was to explore the effects of soil contamination by selected metals (cadmium, copper, nickel, lead or zinc) on the antioxidant response of Vicia faba plants. The levels of the antioxidants: glutathione, proline, non-protein thiols, as well as guaiacol peroxidase and catalase activities were measured in the upperparts of plants. Additionally, the potential bioavailability of metals in the soil and their concentrations in V. faba plants were compared. Treatment with metal caused the problem of an elevation in its bioavailability in soil and its concentration in leaves and stems. The most serious problems seemed to be metal elevations in soil, especially Zn and Ni as well as in the aerial parts of V. faba plants. The antioxidant responses appeared to be metal specific. The elevation of guaiacol peroxidase activity in leaves and stems as well as the proline in leaves was the only more general reaction to metal exposure. Upon analysis of the effects of soil metal contamination on V. faba plants, we recommend the use of some measurements such as guaiacol peroxidase activity and proline level as useful tools in biological monitoring.  相似文献   
676.
This paper presents a general model for energy flow through an animal organism whose consumption and assimilation processes can be described by continuous functions. Two versions of the model are discussed: with continuous and with discrete reproduction. Also, their applicability in analyzing the properties of an actual modelled system is discussed. The results of sensitivity analysis and optimization considerations are presented.  相似文献   
677.
Comparing Pb toxicity to the green alga Stichococcus bacillaris and production of Pb-induced thiol peptides in 24-h exposed cells made it possible to show the level of these peptides to reflect Pb availability to algal cells. LC-ESI/MS analysis of these peptides confirmed that they are phytochelatins PC2-PC4 and their des-Gly derivatives. Studies were carried out at environmentally relevant pH values (5-8.5) and various concentrations of hardness cations (Ca, Mg) and orthophosphate: (0-0.1 mM), chloride (0-100 mM), citrate (0-1 mM), and humic acids (0-10 mg/l). It has been stated, on the basis of the level of Pb-induced thiol peptides, that Pb availability to algae changed significantly within the range of the pH values studied, and was limited in the presence of calcium and of some complexing ligands like orthophosphate, chloride and citrate; it did not decrease in the presence of magnesium or humic acid.  相似文献   
678.
Orliński R 《Chemosphere》2002,48(2):181-186
Polycyclic aromatic hydrocarbons (PAHs) distribution along 28 km of Warsaw main street have been surveyed in July 2000 using moss passive samplers as a simple and economic surrogate of direct air sampling. Altogether 74 samplers at 39 crossroads with traffic lights were placed on the lamp post approximately/=3.5 m above ground. PAHs levels determined in samplers are in range from 828 to 3573 ng/g moss dry weight. The spatial spread of pollution within this range is statistically close to normal distribution with mean value of 2332 ng/g. Variability within and between study areas are rationalized in terms of urban environmental factors. PAHs concentrations profiles across the town have appeared uniform. The dominant compounds are phenantrene, fluoranthene and pyrene. Their contribution is 49-68% of total PAHs burden.  相似文献   
679.
The natural environment of the Carpathian Mountains is one of the richest in Europe in terms of species richness and ecological value. In general, these mountains are well preserved and constitute an important part of Europe's nature resources. The Carpathian area, although divided by political and ethnic frontiers, provides an excellent example of the possibility of protection and conservation of natural and cultural heritage. Natural or seminatural forest ecosystems are the most valuable ecosystems together with man-made meadows and pastures. It is expected that the formerly diverse approaches to nature protection will become unified as the Carpathian countries are incorporated into the European Union. In this paper the various forms of nature protection in the individual Carpathian countries (Czech Republic, Slovakia, Poland, Ukraine and Romania) are described.  相似文献   
680.
A comprehensive method is presented for the evaluation of the living elements of the environment by way of an example of an area situated within the emission range of a non ferrous metal works. The exposure of particular components of the environment is shown using the method of indices, taking into consideration the action of pollutants on the most essential and sensitive receptors. Methods of exposure reduction are also suggested. The proposed method may be helpful in land-use planning in polluted environments and can also be applied to determine the sequence of activities aimed at diminishing the effects of pollution.  相似文献   
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