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81.
Although shell colour polymorphism of the land snail Cepaea nemoralis is a well-known phenomenon, proximate and ultimate factors driving its evolution remain uncertain. Polymorphic species show variation in behavioural responses to selective forces. Therefore, we estimated effects of various environmental factors (temperature, humidity, food availability, (micro)habitat structure and predatory pressure) on behavioural response (frequency of locomotion, climbing and hiding) of C. nemoralis morphs, in experimental and natural conditions. In the experimental part of study, the frequency of locomotion was negatively affected by temperature and the presence of food and positively influenced by the presence of light. Morphs significantly differed in behavioural responses to environmental variability. Pink mid-banded and yellow five-banded morphs climbed less often and hide in shelter more often than yellow and pink unbanded individuals when temperature was low and food was absent. Snails fed most often at moderate temperature compared to low and high temperatures. Field investigations partially confirmed differences among morphs in frequency of climbing, but not in terms of probability of hiding in sheltered sites. In natural colonies, temperature and (micro)habitat structure significantly affected frequency of climbing as well as hiding in shelter. Snails more often hid in sheltered sites where thrushes preyed on Cepaea. Tendency of unbanded morphs to climb trees may have evolved under avian predatory pressure as thrushes forage on a ground. Tendency of banded morphs to hide in sheltered sites may reflect prey preferences for cryptic background. The results implicate that differential behaviour of C. nemoralis morphs compensate for their morphological and physiological limitations of adaptation to habitat.  相似文献   
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The aim of this work is to investigate the application of fly ash adsorbent for removal of arsenite ions from dilute solution (100–1,000 ppm). Experiments were carried out using material from the “Turów” (Poland) brown-coal-burning power plant, which was wetted, then mixed and tumbled in a granulator to form spherical agglomerates. Measurements of arsenic adsorption from aqueous solution were carried out at room temperature and natural pH of fly ash agglomerates, in either a shaken flask or circulating column, to compare two different methods of contacting solution with adsorbent. Adsorption isotherms of arsenic were determined for agglomerated material using the Freundlich equation. Kinetic studies indicated that sorption follows a pseudo-second-order model. Preferable method to carry out the process is continuous circulation of arsenite solution through a column.  相似文献   
83.
This paper attempts to determine whether and to what extent forest birds take the risk of feeding in an open area in winter. In each of three plots the extra food (lard) was initially placed on the border of the forest and open area and then moved into the open area and located within 15, 30 and 45 m from the edge of the forest. Only in one plot the total number of all the birds feeding on lard significantly decreased along with the food being moved away from the edge of the forest. In other plot the number of the most numerous Great Tit Parus major and Blue Tit Cyanistes caeruleus significantly increased along with the food source being moved away into open area. The numbers of the other 7 species of birds fell or did not have directional nature. Only in one plot the aggregation (the number of individuals of a given species feeding simultaneously) increased significantly along with moving the food into open area. In other plots differences in aggregation did not have the directional nature and, in most cases, were not significant.  相似文献   
84.
Aim of the present study was an attempt to find a correlation between physicochemical structure of veterinary drugs and the maximum residue limit (MRL) for muscle tissue of food producing animals. Direct correlation and analysis in quintile groups for 52 physicochemical parameters were performed. An internal validation using leave-one-out cross-validation was performed. In the quintile groups, there were 11 arithmetic expressions created for the limited group of individual parameters (13 from 52 analyzed), which showed a significant linear or quadratic correlation between the number of quintile group and the mean value of MRL within the quintile. The results obtained suggest that there is no direct correlation between individual physicochemical parameters and MRL value in muscle tissue; however, such correlation can be determined for arithmetic expressions created on the basis of several physicochemical parameters, using quintile group analysis.  相似文献   
85.
Correlation of crude oils, or refined products, in the environment with suspected sources is typically undertaken through the use of GC and GCMS and in certain cases bulk carbon isotope compositions. However, with crude condensates, or refined products in particular, the absence, or low concentration, of biomarkers precludes their successful use for making unique correlations. An alternative and, sometimes, complimentary technique for correlation of such products is evolving through the use of combined gas chromatography-isotope ratio mass spectrometry (GCIRMS). This approach permits determination of the carbon and hydrogen isotopic composition of individual compounds in the crude oil or refined product to produce isotopic fingerprints for use in correlation studies. In this paper, it is proposed to review applications of GCIRMS to the correlation of various spilled products with their suspected sources in different environments. Whilst not proposing that this technique will replace GC or GCMS; it is proposed that GCIRMS is a very powerful tool to be used in conjunction with GC and GCMS to make such correlations. Although isotopic fractionation has been observed in some of the lighter components such as benzene and toluene, higher carbon numbered compounds, say above C 10 , do not appear to undergo any significant isotopic fractionation as a result of weathering. Furthermore with refined products, isotopic fractionation of the lighter components has the potential to demonstrate the onset of natural attenuation of refined products in the environment.  相似文献   
86.
Primary objectives of our work were to spatially delineate post industrial areas of the EU-27 and indicate key environmental, social and economic sensitivity issues for these regions. The density of industrial sites within NUTS-x regions for EU-27 countries was assessed by using CORINE 2000 land cover layer. A development of postindustrial society in Europe represents a strong geographic diversity. There are distinct historical and current differences between regions which form major groups, comprising similar internal characteristics and definable trends in environmental and socioeconomic sense. Regions grouped into postindustrial clusters are fundamentally different from the European average, and are facing specific problems related to global market and political changes. Eastern postindustrial regions can be characterized as socially and economically weak, exhibiting high unemployment rate, low GDP, negative population growth and a strong environmental pressure, represented by a high density of dump sites. Most of the western EU postindustrial areas have been successfully recovered and moved into new economy as shown by most of the indicators. In urban postindustrial zones, however, emission sources of pollutants seem to continually be a major problem--not necessarily in terms of exceeding thresholds, but through a remarkable difference in the amount of pollutants produced relative to other regions.  相似文献   
87.
The paper presents results of screening analysis of all Polish national parks (23) contamination with Cd, Cu, Pb and Zn on the basis of a three-level characteristic of heavy metal presence in Norway spruce stands: accumulation on the needle surface, concentration of heavy metals in spruce needles and concentration of bioavailable heavy metals in the soil. Based on the obtained results, the classification of forest ecosystem hazard in national parks with heavy metals was made using synthetic indicators. It was found out that Babiogórski, Magurski, Ojcowski and Gorczański National Parks, located in the southern part of the country, were the most polluted with heavy metals. It is probably due to a higher industrial activity in this part of Poland and the transboundary transport of air pollutants. A little lower level of pollution was observed in Kampinoski National Park located in the middle of the country. The concentration of heavy metals found in needles from national parks does not seem to be harmful for the health status of the trees. Statistically significant correlation between all parameters, which was found for cadmium--the most mobile of the analysed elements--shows that this metal can be proposed as a marker to reflect present effect of industrial emission on forests.  相似文献   
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