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Aura
|
1992
|
nr 12
21-22
The areas affected by thallium pollution include surroundings of cement plants producing Portland cement and clinker, as well as zinc and lead mills. The high toxicity of this element has beer, known for a long time, but no attention has been devoted to it. The symptoms of thallium poisoning are difficult to identify or distinguish from other illnesses, and accurate diagnosis is seldom possible. Although the problem exists in Poland, studies on thallium pollution and its effects generally have not been carried out.
Groundwater chemistry in alluvia was investigated in a meander bend of the Biała Przemsza River in its middle course at Sławków in Upper Silesia, southern Poland. Pollution of groundwater induced by inflow of river water enabled recognition of relative differences in the amount of inflowing water. Biogeochemical zonation is a characteristic feature of the investigated groundwater. Inflow of river water is most intensive in the zone of about 1/3 of the bend width, parallel to the channel. It is characterized by macroions concentrations higher than that in the river. Outside, in the central part of the bend, concentrations of macroions significantly decrease. In this part of the bend, the largest head gradient also is observed. It increases toward the apex, and close to the river channel it equals about 40 cm. Groundwaters in the distal part of the bend are the least mineralized as a result of dilution by rain water. Investigations suggest a slow exchange of the hyporheic waters because of the prevalence of sandy-silty sediments. It favours transformation of nitrates, sulphates, and iron mobility in reducing conditions. Reducing their load in the river can be remarkable over the 30 km meandering reach of this river.
For 40 years the toxic properties of compounds of mercury, cadmium and other heavy metals found in water have been known. That is why it is so important to have information on the excent of sea and river water pollution by these compounds. The contents of these compounds in water vary greatly, which makes continuous monitoring strenuous and expensive. Because of this, since the middle 70s analysis of bottom sediments has been used for defining contamination levels. The author presents this method, often used in Western countries, to the Polish reader.
Relations between changes in bed morphology and heavy metal concentrations were investigated in the Mała Panew River channel in southern Poland. Samples of bed sediments were collected at ten locations 12 times during two years. Concentrations of cadmium, zinc and lead in the river sediments are among the highest in Poland and in silt-clay fraction it reaches 600, 4000 and 500 ppm, respectively. At most channel locations, migration of one or two sand bars was observed. Usually a dead water zone, which was a particularly important sink for fine, strongly polluted organic sediments, appeared in front of the bar. Here, also the highest heavy metal concentrations occurred. The dead water existed usually for several months until it was destroyed by a flood or filled with sand sediments in the case of the bar front accretion. As a result, a marked drop of metal concentrations, accompanied by higher flow velocities, followed in a relatively short period.
W tekście opisano nowo odnalezione stanowiska dwóch gatunków roślin wodnych chronionych w Polsce: kotewki orzecha wodnego Trapa natans L. i salwinii pływającej Salvinia natans (L.) All. położone kilkadziesiąt kilometrów na zachód i wschód od Krakowa. W obu przypadkach rośliny stwierdzono w zbiornikach wodnych pochodzenia antropogenicznego – stawach rybnych w okolicach Chrzanowa (kotewka orzech wodny) oraz na terenie zalanego wodą dawnego wyrobiska żwirowni w Zabierzowie Bocheńskim (salwinia pływająca)
This paper examines the relations between the dispersal of sediment-borne heavy metals and changes in morphology of the Mała Panew River valley in southern Poland. Sediment samples were taken in 66 vertical profiles up to 60 cm deep, situated at different heights above a water table. Alluvial levels of similar width and height appear with different frequency along river banks within 7 selected 1km-long river valley reaches. Moreover, heavy metal concentrations at levels of similar height are similar throughout the Mała Panew valley. This suggests that both the width of the river valley over which sediment-associated heavy metals accumulated as well as the volume of these sediments stored within particular river reaches, change downstream. Generally, the wide, natural reaches of the river valley, which have been sinks for metal-associated sediments in the 20th century, are an important secondary pollution source, whereas narrow valley reaches in which flow regulation caused incision of the river channel are mainly transition zones for the polluted sediments conveyed in the river valley.
The content of Zn, Cd, Pb, Ni, Mn and Fe in bottom sediments of water reservoirs in Cracow has been investigated. Concentrations of heavy metals appeared to be more related to reservoir type and age than location. The most polluted sediments occur in river meanders cut in present time as well as in reservoirs affected by waste disposal. Reservoirs located in open pits are not polluted. However, reservoirs without inflow and outflow are the most sensitive to the accumulation of toxic metals. These reservoirs seem to be the most suitable for recreation.
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