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Experimental evidence has indicated that dietary zinc level may modulate the accumulation and toxic response to lead, cadmium and mercury. Insufficient zinc intakes have been shown to increase the risk associated with the exposure of animals to these heavy metals. On the other hand, moderate zinc supplements have been found to have a marked effect in preventing the deleterious effect produced by lead, mercury and cadmium. The mechanism by which dietary zinc may influence risks from lead, cadmium and mercury is not fully understood; however, the factors involved in the absorption from the gastrointestinal tract are of considerable concern.
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Soil samples for analyses were collected in the whole area of the Cracow province. Basic soil properties and content of heavy metals were determined in the soil samples. It was found out that 47% of the examined soils of the Cracow province should be classified as the soils with elevated cadmium levels, 10% are soils with elevated lead levels and 27% are the soils with elevated zinc levels. The remaining soils should be classified as the soils with a natural content of these elements. Nickel and copper concentrations in all the examined soils are in the range of the natural content. The calculated correlation coefficients show that the content of cadmium was determined by the soil pH and content of copper by the content of C-org.
Polluted air is a stress factor that contributes to the decline of urban trees. Air pollution may cause short-term (acute) damage, which is immediately visible and long-term (chronic) damage, which can lead to gradual tree decline. Long-term damage may predispose trees to other disorders. The impact of technogenic factors on the leaf’s anatomical structure of Acer negundo L. (Box elder) was studied. The thickness of the upper cuticle is increased when compared to those from an ecologically pure area. A change in the rate of mesophyll tissue is due to the enlargement of the palisade parenchyma. The thickness of lower epidermal cells is decreased. All changes of the leaf blade structure are significant and are in direction of increasing the xerophyte characteristics of the leaves. Box elder is native to much of temperate North America. This is a tree of lowlands and wet hardwood forests. As such, we can assume that the registered changes are adaptive responses of the tree to the contaminated environment and that the tree can be considered to be relatively tolerant.
The research was conducted to evaluate the impact of sulphur compounds on the sex of Colorado potato beetle in the region of sulphur factory in Chmielów near Tarnobrzeg in 1995. The control plantations were situated in the village of Zarębki, about 30km from Chmielów. The object of the study was the average body mass of female and male specimen of the insect after full spring beetle appearance in potato plantations as well as the average body female and male mass after pupation of the larvae of the first generation and emerging from the soil. After six and twelve days of starvation, the average female and male body mass was determined. After twelve days of starvation the incident of cannibalism was noticed among the beetles of the first zone polluted by sulphur compounds.
During a period of 60 days assays were carried out with the moss Pohlia nutans transplanted from an uncontaminated control site to a dump consisting of a heavily polluted mine and smelter wastes located near Wałbrzych in southwestern Poland. Within the same period also samples of native P. nutans growing on the dump substrate were collected together with the same species from a control site. Concentrations of Al, Fe, Cd, Co, Cr, Cu, Mn, Ni, Pb, V, and Zn, as well as N, P, K, Ca, Mg and S, were determined in P. nutans, the dump substrate and the soil of the control site. Atmospheric deposition was the main contribution to the levels of Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn in the native and transplanted P. nutans on the examined dump. The obtained results indicate that the transplanted P. nutans accumulated significantly more Al, Cd, Co, Cr, Fe, Ni, Pb and Zn than the native moss.
Oznaczono stężenia fluorków w łożyskach gromadzonych w ciągu kilku lat, pochodzących od kobiet zamieszkujących tereny bezpośrednio sąsiadujące z zakładami chemicznymi emitującymi związki fluoru. Stwierdzono tendencję do obniżania się stężenia fluorków w badanym materiale wraz z poprawą sytuacji ekologicznej wokół źródła emisji. Zjawiska tego nie potwierdzono statystycznie, co wyklucza przydatność łożysk ludzkich jako bioindykatora w ocenie stopnia skażenia środowiska związkami fluoru.
W pracy przedstawiono wyniki badań wpływu emisji przemysłowych zawierających związki fluoru na profil lipidów osocza owiec pochodzących z terenów Pomorza Zachodniego.
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