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Łubin w nawożeniu szkółek leśnych w Sudetach

63%
Samples for analysis were collected from 10 areas, including the major Polish rivers and lakes, with different sources of environmental pollution (industrial, municipal, and farming). The materials was taken from the lakes of Mazury, located in anon-industrialised region, from the Brda River, an area impacted by pig farms, from the lakes of Lipczyno Wielkie/Pomerania, from the Wkra River, an area impacted by poultry farms, from the Dunajec River at the Roznowski Reservoir, from the Vistula River at Cracow and Warsaw, from the Odra River at Wroclaw and the Warta River estuary, and also from Rybnik Power Station Reservoir. Concentrations of Pb, Cd, Hg, and As were analysed in 397 fish muscle and 128 sediment samples using an atomic absorption spectrometry technique. The analytical procedures were covered by a quality assurance programme. It was demonstrated that the average concentrations of lead, cadmium, and arsenic in fish were in the low hundredths and thousandths of a mg/kg and never exceeded permitted limits established for food. Higher values of these elements were found in fish from bodies of water located in the zone of influence of large urban agglomerations, especially the Cracow region. High concentrations of lead and cadmium were also found in Vistula River sediments near Cracow, where the maximum values were 134.10 mg/kg and 21.24 mg/kg dry weight for lead and cadmium respectively. The average concentration of mercury in a predatory fish muscle (0.179 mg/kg) was almost twice as high as in the omnivorous fish (0.103 mg/kg). Only a single fish sample exceeded the maximum limit for this metal (0.50 mg/kg) and did not present a risk to consumers' health.
The aim of the study was to evaluate the contamination of animal muscle, liver, and milk with lead, cadmium, mercury, and arsenic. Determination of the elements was carried out using several techniques of atomic absorption spectrometry. Between 2008 and 2012, samples of muscles and liver from 1305 cattle, 2345 pigs, 758 horses (only muscles), 1721 poultry (chickens, turkeys, geese, ducks), and 736 samples of raw milk were collected. Only 48 (0.7%) samples exceeded the maximum acceptable levels of the elements, especially lead and cadmium. In the case of lead, the highest number of samples exceeding the legal limits was Ibund in muscles of pigs (6), where the maximum value reached 0.376 mg/kg. For cadmium, the highest number of samples (22) with values exceeding legal limits was found in muscles of horses. The cadmium content in muscles of horses, at both the mean (0.052 mg/kg) and median (0.023 mg/kg), was in order of magnitude higher than that observed in cattle and pigs. Small percentage of samples with values exceeding the maximum levels of toxic elements in food of animal origin indicates a low risk for the consumers' health.
The aim of this study was to assess the degree of contamination of boar, roe deer and red deer (muscle, liver) tissue with toxic elements in the last 12 years and to determine the causes of risks for game meat consumers. The tissues collected from wild game, including 571 wild boars, 305 roe deer and 420 red deer were examined for lead, cadmium, mercury and arsenic content. Determining the content of lead, cadmium, mercury and arsenic was conducted using several techniques of atomic absorption spectrometry. The procedures used in metal determinations were elaborated and validated, and are regularly checked in intralaboratory and interlaboratory comparisons. It was stated that lead constitutes the most serious toxicological problem within the group of analyzed metals. The average concentration of this element over 12 years in the muscles of boar, roe and deer was respectively: 0.280 mg/kg, 0.224 mg/kg and 0.152 mg/kg. The average values for liver reached a much lower level and were as follows: 0.107 mg/kg, 0.111 mg/kg and 0.136 mg/kg. Such a reversal of the relationship between the size of the concentration in the muscles and organs indicates that the source of lead contamination in game animals is primarily a secondary pollution from gunshot wounds rather than an environmental one. The percentage of muscle samples tested in 2001-2012 with values above a tolerable limit of lead was about 10%, and the highest number of samples was found in 2001 and 2002. A significant proportion of samples with high levels of lead pose a particular threat to human health even in low consumption of game animal meat. The observed concentration levels of cadmium, mercury and arsenic in the examined tissues of wild game indicate that they are mainly associated with environmental pollution.
On the basis of forest taxation data the presence of European ash in the Bardzkie Mountains area (central part of the Sudety Mountains) was analysed. This included the reckoning of the number of sites and the area covered by ash in various forest habitat types, age classes, altitude zones and on variously slanted and exposed mountain sides. The decline in the number of ashes in younger age classes and complete absence of trees older than 140 years have been noted. In the Bardzkie Mountains ash is the main species forming the forest on mountain riparian forest stands (a 43% participation in the area of forest of this type). Considering the number of specimens most ashes are scattered in mountain broadleaved forest. To the altitude of 650 m ash’ participation in the forest stand composition is stable (30% of analysed locations), but it occupies only 2.6% of total forest area.
The paper presents results of floristic research of vascular plants in the nature reserve “Cisy” located near Bardo town in Bardo Mts (south-western Poland). Altogether 144 species have been found. Some of them are rare and threatened in Poland, e.g. Cephalanthera longifolia, Dactylorhiza sambucina, Neottia nidus-avis, Platanthera bifolia and Taxus baccata.
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