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671.
Larch Bolete (Suillus grevillei) mushrooms collected at spatially distant sites in Poland showed on relative abundance of K, P, Mg, Rb, Al, Ca, Fe (at mg/g dw), Ag, Ba, Cd, Cu, Mn, Na and Zn (at microg/g dw) and less of Co, Cr, Ni, Pb and Sr (<1 microg/g dw). Amongst these elements Rb and K were highly bioconcentrated by Larch Bolete (BCF around 1000 and 300 for the caps), and weaker were Cu, Mg, Na, P and Zn (BCF between 4.1+/-2.5 and 62+/-21). Ag and Cd were bioconcentrated mainly in caps with BCF value of 25+/-16 and 13+/-10. Al, Ba, Ca, Co, Cr, Fe, Mn, Ni, Pb and Sr were excluded (BCF<1) by this species. Intake of meal prepared of 300 g of fresh fruiting bodies of Larch Bolete picked-up at the Western Beskid or Pogórze Wielickie sites in the south of Poland will result in exceeding of oral reference dose set for cadmium. In the case of silver, copper or zinc content a meal of 300 g of fresh or 30 g dried Larch Bolete will not result in exceeding reference doses for these elements. Extent of dose that customer would be exposed after eating of three 300 g fresh the Larch Bolete meals during a week will led to intake of lead and zinc within margin of 0.9-5.1% and 9-16% of PTWI for these elements, respectively. In the case of cadmium and specimens from the Western Beskid or Pogórze Wielickie sites in the south of Poland intake will slightly (around 10%) exceed PTWI value, and for other sites will not exceed (between 2% and 26% of PTWI).  相似文献   
672.
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   
673.
The aims of this study were to characterize soils from industrial sites by combining physicochemical, microbiological, and ecotoxicological parameters and to assess the suitability of these assays for evaluation of contaminated sites and ecological risk assessment. The soil samples were taken from long-term contaminated sites containing high amounts of heavy metals (sites 1 and 2) or petroleum hydrocarbons (site 3) located in the upper Silesia Industrial Region in southern Poland. Due to soil heterogeneity, large differences between all investigated parameters were measured. Microbiological properties revealed the presence of high numbers of viable hetrotrophic microorganisms. Soil enzyme activities were considerably reduced or could not be detected in contaminated soils. Activities involved in N turnover (N mineralization and nitrification) were significantly (P?<?0.05) higher in samples from the metal-contaminated sites than in samples from the hydrocarbon-contaminated site, whereas the opposite was observed for phosphatase activity. The Microtox test system appeared to be the most appropriate to detect toxicity and significant differences in toxicity between the three sites. The Ostracodtoxkit test was the most appropriate test system to detect toxicity in the hydrocarbon-contaminated soil samples. Correlation analysis between principal components (obtained from factor analysis) determined for physicochemical, microbiological, and ecotoxicological soil properties demonstrated the impact of total and water-extractable contents of heavy metals on toxicity.  相似文献   
674.
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   
675.
The distribution, excretion and metabolism of 1,3-dibromobenzene following a single i.p. administration to rats 100 or 300 mg/kg was investigated using radiotracer [3H] and GC-MS technique. After 72 hours about 74 to 90% were excreted in urine. The highest radioactivity was observed in the liver, kidneys and fat tissue. Later on a steady decline of radioactivity was apparent in all investigated tissues except for blood cells and the sciatic nerve, where constant levels were noted. In urine the following substances were identified and quantified by GC peak areas: unchanged 1,3-DBB (18%), dibromophenols (34%), dibromothiophenols (28%), dibromothioanisole (1.8%), bromophenol (5.5%), bromohydroxythiophenols (5%), and bromohydroxythioanisole (7.5%).  相似文献   
676.
The charcoal kilns under study were situated in the Polish Western Carpathiens (Bieszczady). Aromatic hydrocarbon products of wood burning in the kilns were identified. The rate of decomposition of beech leaves was relatively high as environmental conditions enhanced decomposition. The intensity of soil metabolism is increasing during a long-term exposure to smoke, which is one of the indicators of anthropogenic disturbance resulting from organic factors.  相似文献   
677.
Among commonly employed methods of fast estimation of the soil biological activity a method of the oxygen consumption determination is used. The main goal of this research was an estimation of a soil respiratory metabolism using the constant pressure volumetric respirometer and also using the flow-through respirometer UNI-RES10.Soil respiration measurements were done using both types of respirometers in temperatures 10, 15, 20, 25, 30 and 35 °C, keeping up the constant humidity. The investigated soil was a soil humus belonged to organic soils from the Dziekanów Leny field. The soil respiration was also measured for 8 plant communities in Sudeten Mountains with various respiration intensity.After the experiments it was stated that both measuring instruments could be used for the soil metabolism evaluation. Readouts obtained from the UNI-RES10 respirometer are smaller then readouts when using the constant pressure volumetric respirometer. The flow-through respirometers have to be calibrated to obtain results comparable with these from volumetric ones. The volumetric and flow-through respirometry methods are useful for the comparative analysis of metabolism levels.  相似文献   
678.
A Health Index/Risk Evaluation Tool (HIRET) has been developed for the integration of risk assessment and spatial planning using GIS capabilities. The method is meant to assist decision makers and site owners in the evaluation of potential human health risk with respect to land use. Human health risk defined as the potential adverse effects on human life or health is generally accepted as the most important aspect for site assessment and planning of remediation strategies. It concerns polluted sites that endanger human health on one hand and derelict land that does not cause the immediate risk on the other hand. In current state-of-the-art risk-assessment, long-term spatial and temporal changes of risks, in relation to changes in contamination patterns and land use functions, are not taken into account. The aim of this paper is to demonstrate the methodology developed for human health risk assessment in aspect of spatial and temporal domain. HIRET was developed as an extension for ESRI software ArcView 3.2 and allows performing dynamic human health risk assessment in long-term period, which is relevant for land use planning. The paper illustrates how such methodology can assist in environmental decision-making to enhance the efficiency of contaminated land management. A case study of contaminated site is given showing how data can be used within a GIS framework to produce maps indicating areas of potential human health risk.  相似文献   
679.
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   
680.
The use of terrestrial mosses as biomonitors in large-scalemulti-element studies of heavy metal deposition from theatmosphere is a well established technique in Europe. Insuch studies it is advantageous to determine as many elements as possible in order to distinguish betweendifferent source categories. A combination of INAA and AAShas been found very useful in this respect, in particularwhen epithermal activation is used for instrumental neutronactivation analysis. A total of 33 elements (Al, Cl, Sc, V,Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Rb, Sr, Ag, Cd, Sb,I, Cs, Ba, La, Ce, Tb, Yb, Hf, Ta, W, Au, Pb, Th, and U) inPleurozium schreberi (Brid.) Mitt. moss samples fromthe Silesia-Kraków Industrial Region and Legnica-GogówCopper Basin and from the control (background) area inNortheast Poland were identified. The highest concentrationsof the majority of trace elements were found in mossesgrowing in the Silesia-Kraków Industrial Region, only Cu andAs concentrations were higher in mosses in the Legnica-Gogów Copper Basin. These results are in conformity withthe load of trace elements emissions in these areas.  相似文献   
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