Accumulation of trace elements in bottom sediments of the Otmuchów and Dzierżno Duże reservoirs (Odra river basin, Southern Poland)

Skład chemiczny osadów dennych zbiorników wodnych określono meto-dami ICP i INAA. Dowiedziono, że niektóre z mikroskładników (As, Ba, Co, Cr, Cu, Ni, Pb, S, Sr, V, Zn) znacznie od-biegają ilością od poziomów uznawanych za naturalne w osadach wodnych Polski. Osady denne zbiornika Otmuchów reprezentują klasy osadów od praktycznie niezanieczyszczonych do silnie zanieczyszczonych (-1,26 Igeo < 3,89), osady zbiornika Dzierżno Duże mieszczą się natomiast w przedziale od niezanieczyszczonych do ekstremalnie zanieczysz-czonych (0,34 Igeo < 5,20). Wskaźniki zanieczyszczenia świadczą o umiarkowanym zanieczyszczeniu osadów dennych zbiornika Otmuchów (0,1 < Cif < 3,4) i nawet bardzo wysokim zanieczyszczeniu osadów dennych w zbiorniku Dzierżno Duże (0,7 < Cif < 8,5). Stopień zanieczyszczenia osadów dennych jest niski w przypadku zbiornika Otmuchów (Cd = 5,2), a w przypadku zbiornika Dzierżno Duże (Cd = 22,6) świadczy o znacznym zanieczyszczeniu. Wzbogacenie składu che-micznego osadów, świadczy o kumulacji w osadach dennych pierwiastków śladowych, które wobec przekroczenia tła geochemicznego należy utożsamiać z zanieczyszczeniami

Cadmium contamination of sediments in the water reservoirs in Silesian Upland (southern Poland)

Purpose Cadmium (Cd) is considered a toxic element and its concentrations are relevant to human health and the environment. Therefore, the purpose of the study was to determine the extent to which the bottom sediments of water bodies (artificial lakes and ponds) in the Silesian Upland in southern Poland are contaminated with Cd; an attempt was also made to determine the factors that condition spatial differences in the concentration of this element between individual water bodies in the region. Materials and methods Measurements of the Cd content in bottom sediments were carried out in 35 water bodies in southern Poland in 2011 and 2012. Depending on the surface area and morphometric characteristics, from two to nine samples representative in terms of sediment thickness were collected in each water body. Cadmium concentrations were determined for 92 0.25 g aliquots using the TD-ICP method. Results and discussion Cadmium content in all samples (0.7–580.0 mg kg−1) was higher than the natural range of concentrations for this element in the Earth’s crust (0.1–0.3 mg kg−1) and the geochemical background for Poland (0.5 mg kg−1) and, with a few exceptions, was also higher than the preindustrial concentration (1.0 mg kg−1) and the regional geochemical background (2.5 mg kg−1). Adopting natural Cd concentrations in the Earth’s crust (0.1–0.3 mg kg−1) as the baseline for the geoaccumulation index (Igeo), the sediments examined can be classified as extremely and heavily contaminated (and moderately contaminated in a small number of cases). The assessment of sediment quality based on Igeo, with the regional geochemical background (2.5 mg kg−1) adopted as the baseline, results in non-contaminated and moderately contaminated sediments being dominant with a far smaller number of heavily and extremely contaminated ones. Conclusions In the case of several water bodies, Cd concentrations were at record levels that have not been found anywhere else in the world. On the basis of the Igeo, sediments of varying quality were found—from virtually uncontaminated to extremely contaminated. The Igeo index as an indicator of the quality of bottom sediments is a measure that requires careful interpretation, especially when different concentration levels regarded as natural are used for determining its value

Mill pond sediments as the indicator of the environment of the drainage area (an example of Liswarta River, Odra basin, Poland)

The geochemical characteristics of sediments deposited within a channel-type reservoir situated behind the weir of a water mill on the River Liswarta (southern Poland) were studied in relation to land use in the catchment. The catchment in question is an agricultural one with large forest areas. The contamination of sediments with trace elements was assessed using the geoaccumulation index. The sediments studied were moderately to heavily contaminated with As, Cu, Co, Ni and Ba. They were also heavily contaminated with Sr. Additionally, V and Cr contamination ranged from heavy to extreme. The basic composition of sediments and the trace elements present in them indicate both natural and anthropogenic sources of pollution. Mill impoundments provide zones where the sediments transported by rivers accumulate. Within the Liswarta catchment, their removal may cause the remobilisation of contaminated alluvial deposits

Symplectic quaternion scheme for biophysical molecular dynamics

Massively parallel biophysical molecular dynamics simulations, coupled with efficient methods, promise to open biologically significant time scales for study. In order to promote efficient fine-grained parallel algorithms with low communication overhead, the fast degrees of freedom in these complex systems can be divided into sets of rigid bodies. Here, a novel Hamiltonian form of a minimal, nonsingular representation of rigid body rotations, the unit quaternion, is derived, and a corresponding reversible, symplectic integrator is presented. The novel technique performs very well on both model and biophysical problems in accord with a formal theoretical analysis given within, which gives an explicit condition for an integrator to possess a conserved quantity, an explicit expression for the conserved quantity of a symplectic integrator, the latter following and in accord with Calvo and Sanz-Sarna, Numerical Hamiltonian Problems (1994), and extension of the explicit expression to general systems with a flat phase space

Composition and physico-chemical properties of bottom sediments in the southern part of the Bratsk Reservoir (Russia)

The paper presents the results of studies of bottom sediments taken from the southern part of the Bratsk Reservoir. The following analyses have been conducted: trace element analysis, particle-size analysis as well as chemical analysis of water, hydrochloric acid and alkaline extracts for 18 samples of the bottom sediments. The granulometric analysis has identified the predominance of fine silt and silty-clayed sediments. The data on the content of trace elements in the bottom sediments of the Bratsk Reservoir is presented in comparison with their content in the natural environment of the Baikal region; the anomaly ratio was used to characterize the excess for trace elements. The chemical analysis of extracts has showed “saline contamination” of mud (silt), high concentration of carbonates in it, as well as the presence of mobile (free) forms of aluminum oxide. In this research, an attempt was made by using a correlation analysis to evaluate the impact of various physical and chemical characteristics of the bottom sediments, such as the content of clay fraction, organic carbon, carbonates, and water-soluble salts on the accumulation of trace elements

The development of freshwater deltas and their environmental and economic significance

The article presents the results of studies concerning the delta forms that arise as a result of the sedimentation of the debris fed to water bodies by watercourses. The study covered several dozen anthropogenic water bodies in the Upper Silesia region, which is well known for its high degree of urbanisation and industrialisation. Basic research work included morphometric measurements of deltas, analyses of the mechanical and chemical composition of delta sediments and analyses of the chemical composition of the common reed growing on the deltas. The research has demonstrated that the deltas exhibit certain characteristics typical of anthropogenic forms that result from the pollutants found in watercourses. In delta sediments, grains of sand usually dominate, but in many cases the share of the < 0.02 mm fraction is as high as ca. 30%. Sediments often contain fine coal and other organic pollutants, which is reflected by high weight loss on ignition. The content of trace elements in delta sediments is usually many times higher than the geochemical background for all types of sedimentary rocks. Deltas are an environment where pollutants accumulate and some of them are assimilated by plants. The content of macro elements in common reed tissues from different deltas does not vary widely while the content of trace elements often results from their content in the sediments. The material that forms deltas can be extracted and in some cases even used as fuel