Pollution of middle and lower section of Odra river with selected heavy metals on the base of results of geochemical monitoring of bottom sediments in the years 1991÷2005

Odra jest jedną z najważniejszych rzek Polski, jej dolina jest ważnym korytarzem ekologicznym, niezwykle cennym przyrodniczo. Rzeka jest odbiornikiem ścieków zarówno oczyszczonych, jak i nieoczyszczonych, pochodzących często ze źródeł niekontrolowanych. Zanieczyszczenie wód i osadów dennych rzeki uniemożliwia rekreacyjne wykorzystanie rzeki i zagraża środowisku - miedzy innymi doskonale zachowanym, unikatowym dziś w Europie, bezcennym wręcz lasom nadrzecznym: grądom i łęgom. Pośredni wpływ na jakość wód Odry ma stan gospodarki wodno - ściekowej na obszarze całej zlewni - poprzez jakość wód jej głównych dopływów. Stan czystości Odry w jej środkowym i dolnym biegu uzależniony jest w znacznej mierze od wpływu zanieczyszczeń ze źródeł zlokalizowanych na Górnym i Dolnym Śląsku; przyjmuje również zanieczyszczenia z terenu Niemiec i Czech. Osady denne odgrywają ważną rolę w systemach wodnych, zarówno jako zbiorniki, gdzie zanieczyszczenia mogą być przechowywane, jak i źródła tych zanieczyszczeń dla organizmów wodnych. Z powodu ich zdolności do zatrzymywania metali, osady denne są dobrym wskaźnikiem jakości wody i zapisem skutków działalności antropogenicznej. Stąd też są szeroko stosowane w badaniach środowiskowych. Znajomość składu chemicznego osadów jest w wielu przypadkach lepszym wskaźnikiem zanieczyszczenia środowiska, niż znajomość składu chemicznego wody, bardziej zmiennego w czasie. Problem zanieczyszczenia osadów dennych jest coraz bardziej doceniany. Ocena zanieczyszczeń osadów, obok oceny jakości wód, służy ocenie jakości ekosystemów wodnych, tym bardziej, że zanieczyszczenia osadów dennych stanowią zagrożenie dla sąsiadujących z nimi ekosystemów lądowych. Celem pracy było porównanie zanieczyszczenia osadów dennych środkowej i dolnej Odry na odcinku Nowa Sól - Police w latach 1991÷2005 w ujęciu przestrzennym i czasowym.The estimation of pollution degree of Odra River bottom sediments (middle and lower section) by selected heavy metals has been carried out on the basis of monitoring data recorded in the years 1991÷2005. Classification of sediments proposed by Polish Geological Institute (PIG) was applied. Also trends of changes of heavy metals concentrations in the Odra River bottom sediments in this period of time and changes of heavy metals concentrations in 1991, 1996, 1997 i 2005 years have been presented. In the period of time 1991÷2005 the reduction of metal concentrations in sediments of middle and lower Odra River in Nowa Sól-Police section has been particularly noticeable since mid 90-ies in the last century. Within the analysed section of the middle Odra River very polluted sediments of IV class occur (mainly because of mercury concentrations). However in the lower Odra River sediment serious metalic pollutions are not noticed - these sediments most often were non-polluted by PIG classification. In 1991, 1996, 1997 i 2005 years concentrations of some heavy metals in sediments of the analysed section of middle and lower Odra River both within the space and time approach, achieved the lowest values - of I and II class. Observable a slope trend of metals concentrations in the Odra River bottom sediments is caused by decreased inflow of pollutants. The quality of bottom sediments in the analysed section of the middle Odra river reflected influence of pollutants carried by the river from industrial areas laid in its upper section. Along with the river run, due to progressive sedimentation of suspensions improvement of the quality of river's bottom sediments is observed. Also spatial differentiation of heavy metals content in sediments is levelling from year to year - in 2004 only sediments in highest located Nowa Sól were still polluted, mainly with mercury and zinc, sediments in the lower section were already of satisfactory quality. In the years 2004÷2005 on the whole analysed section of middle and lower Odra river sediments were not polluted or at most moderately polluted. Clear downward trend of heavy metals content in bottom sediments of the Odra river is a result of reduced inflow of pollutants into the river in form of wastewater, superficial inflow and precipitations, as a result of, among others, the growing quantity of wastewater treatment plants, pro-ecological agriculture and decrease of pollutants emission to the atmospher

Preliminary study of heavy metal pollution in the floodplain sediments of the Lubusz Oder Gap

Floodplains are places of accumulation and secondary release of metals. The polluted water sediments which are stable during normal river flows can erode in the times of floodings and high water stages. In such periods, the pollution of the bad sediments, river waters and the floodplains increases. In environmental research, determining the total metal content does not provide information about their mobility or availability. The toxic effects depend on their chemical form. In this paper, single extraction procedures have been used to determine the forms of easily available metals. Three types of extractants have been used: neutral salt solution (0.01M calcium chloride), mineral acid solution (0.1M chydrochloric acid) and complexing reagents (0.02M ethylenediaminetetraacetic acid (EDTA) and 0.005M deiethylene triamine pentaacetic acid (DTPA)), to determine the extraction effectiveness. The study presents the results of preliminary research of pollution with selected metals (cadmium, chrome, copper, nickel, lead, zinc, iron and manganese) of the Middle Odra Valley. Higher total concentraions of metals were found in the areas currently flooded by the Oder River

Fractionation of some heavy metals in bottom sediments from the middle Odra River (Germany/Poland)

cited By 18International audienceFractionation of Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn has been performed in bottom sediment samples collected along a 75 km section of the middle Odra River by a modified method of 5-step sequential extraction according to Tessier. The results have shown the presence of Cu, Ni, Zn and Mn already in exchange fraction (I); the mean percent content of metals in mobile phases (exchange and carbonate) reached 35% (Cu), while the maximum values reached 59% (Ni). From among the metals studied, Zn, Mn, Fe, Cr and Ni were dominant in the species bound to hydrated iron and manganese oxides, so the metals contained in the bottom sediments were not permanently immobilized. Good correlation was found between th e concentrations of Zn, Mn and Cd in the mobile phases (I+II) and their total concentrations. Similarly, the concentrations of all metals determined in the reducible fraction and in the fraction bound to organic matter (except for Cd and Cr) were well correlated to their total content