Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 9

Liczba wyników na stronie
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników

Wyniki wyszukiwania

help Sortuj według:

help Ogranicz wyniki do:
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
The extensive investigations of total and mobile heavy metals concentrations in sus­pended matter (SPM) and bottom sediments of the upper and middle Odra river were carried out over the years 1997–2000. Significant levels of contamination were found. Median concentrations for Cd, Pb, Cu, Zn and As in the SPM and sediments were (mg/kg) 7.3 and 8.9, 97.2 and 119, 79.2 and 92.7, 1221 and 1158, and 52.9 and 67.9, respectively. The highest metal pollution of Odra river solids was found with cadmium, zinc, lead and arsenic. The frequency distribution of Cd, Zn, Pb and As in both type of samples, i.e. SPM and sediments, shows high similarity. >From all metals studied, Cd, Zn and As appear to be of particular concern because of the high levels, that appear to be bio­available, and their high mobility. The exchangeable and carbonatic fractions of Cd and Zn reached up to 50% of their total amount. Besides the determination of total metal concentration, the “mobilisation test” of metals in river solids is rec­ommend for monitoring purposes, allowing evaluation of the most mobile, and bioavailable metal fractions. The results of four years of very wide studies of Odra river system suggest that for river monitoring pur­poses, the fre­quency and numbers of samples for chemical analysis of both water and solids - preferably suspended matter - could be reduced to twice a year, with few select sampling sites.
The aims of this study were to asses an environmental condition and observe changes of heavy metal con­cen­trations and distribution in water of the upper and middle Odra River. In order to estimate levels of heavy metal pollution in the upper and middle Odra River and its tributaries, in May and November 1998, June 1999 and May 2000, a total of 147 samples of river water were taken. Heavy metals (Zn, Pb, Cu, Cd, As, Cr, Ni, Mn, Fe) in the water samples were analysed by ICP-MS. According to the LAWA classification, water in the Odra River and its tributaries are moderately to highly con­tami­nated with heavy metals. High metals concentration is mainly due to ag­ri­cul­tural and industrial activities such as pet­ro­chemi­cals, petroleum refining, steel works foundries and non-ferrous metal-works. The lev­els of pollution vary in wide ranges, depending on the metal. Highest Cd, Cu and Zn con­cen­trations were observed par­ticu­larly in middle part of the Odra River at the Lubin - Legnica Cu-mining and processing region.
The discharge of high flood water (2010) into reservoirs located in the Upper Vistula River catchment and into the overloaded Vistula River channel may strongly affect water and sediment quality. To investigate the contamination of the flooded area in the center of Cracow, total of 32 sediment samples were collected along the length of the Vistula River and also from the cross section in the floodplain area. Additionally, 12 samples of the flooded sediments were collected along the Wilga River – a tributary of the Vistula located within the investigated area. The concentrations of Zn, Pb, Cd, Cu, Mn, Zn, and Fe in the bulk samples and size fraction <20 µm were studied. The metals concentration in the Vistula River flood sediment samples varied in wide ranges (mg/kg): Zn 59-1013, Pb 17-263, Cd 2.6-23, Mn 145-469, and Fe 0.70-3.59%, and was considerably higher in the size fraction samples. The concentration of Cu was low and reached up to 40 mg/kg. The highest amount of Zn was found in the sediment sample from the cross section, located 38 m from the Vistula River channel. Three-step sequential extraction revealed the most mobile metals in the sediment fraction <20 µm, which were as follows: Cd (77% of the total amount), Pb (55%), and Zn (42%). The contamination of the Wilga River flood sediments was lower when compared with Vistula River contamination.
Part I describes the organizogram and objectives of the International Odra Project (IOP) for the 1997 – 2001. Scientific teams from Germany and Poland took part in the project. The main objective of the IOP program was to describe the status, trend dynamics and metabolic pathways of all types of pollution in the Odra river basin. A scientific task realized by the team from ...... University of Technology (GUT) was to assess the pollution level of organic compounds in water and sediments from the Odra river catchment area. Parts II and III will present the results obtained by the GUT team, which consist of determinations of organic pollutants in water and sediments. The assessment of heavy metals contamination and its mobilisation in water, suspended matter and bottom sediments of the upper and middle Odra river was the main task of the research group from the University of Mining and Metallurgy in Krakow. The obtained results are presented in Parts IV and V.
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.