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Matys Grygar Tomáš Sedláček Jan Bábek Ondřej Nováková Tereza Strnad Ladislav Mihaljevič Martin 《Water, air, and soil pollution》2012,223(2):739-753
Regional contamination by Pb and Zn in southern Moravia (south-east part of the Czech Republic) in the twentieth century was
analysed in Brno Dam lake sediments and in floodplain sediments of the Morava River near Strážnice. The age model for the
Brno Dam lake sediments has been obtained by 137Cs (maxima corresponding to the nuclear tests in atmosphere and the 1986 Chernobyl accident) and the construction of the dam
(1940); the time constraints for the Morava River sediments was the erection of flood defences (1930s) and 210Pb dating. In the case of floodplain sediments, profiles exhibiting post-depositional mobilisation of heavy metals by pedogenic
processes (gleying) must be excluded to reconstruct the history of contamination. There was a relatively fast joint onset
of Pb and Zn load since the early stages of industrialisation in the first half of the twentieth century, but then the concentrations
of these two metals developed in a different manner. Pb load only slightly increased till its peak in 1960s and 1970s. The
increase of Zn load was rather stepwise: Soon before 1930s (Morava River floodplain) and in 1940s and 1950s (in Brno Lake),
the relative contamination by Zn was much lower than during its peak in the 1970s to the present days. The offset of Pb and
Zn contamination curves could have been caused by three different artificial sources of these heavy metals. The temporal shift
of Pb and Zn loads can be used for dating sediments. 相似文献
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Tomáš Matys Grygar Jitka Elznicová Tereza Lelková Timea Kiss Márton Balogh Ladislav Strnad Tomáš Navrátil 《Journal of Soils and Sediments》2017,17(11):2596-2609
Purpose
The Oh?e River has received contamination from metal mining and metallurgy (mainly Cu, Pb, Sn, U, Zn) over the previous five centuries. This contamination history has been poorly documented. Contamination has entered the river system in its middle reach, where the channel is incised and bedrock confined, which impedes overbank deposition. Our objective was to locate and describe a sedimentary record in this unfavourable depositional setting.Materials and methods
Three former channel bars that have coalesced with the riverbank were revealed by examination of historical and current maps and a digital terrain model. Manual coring in the bar and in situ (handheld) X-ray fluorescence (XRF) spectroscopy provided data for developing a contamination chemostratigraphy, which was correlated with the mining history in the region. Detailed topographic examination of the bar and valley edge was important to understanding the evolution of one of the bars. Optically stimulated luminescence (OSL) dating was used to verify the timing of deposition.Results and discussion
Handheld XRF for in situ analysis of element composition is efficient for studying contaminated sediment bodies with complex stratigraphy, which require extensive coring and stratigraphic correlation. Despite the unfavourable settings, the channel bars trapped sufficient sediment to produce a record that correlates with the history of contamination in the drainage basin. In the bar studied in greatest detail, we observed a surprising amount of contamination passing through the Oh?e River channel (up to 300 mg kg?1 of Cu, 340 mg kg?1 of Pb and 630 mg kg?1 of Sn in fine sand and silt deposits) associated with a pollution climax in the sixteenth and seventeenth centuries. Modern contamination (Hg and U deposited in the nineteenth and twentieth centuries) was entrapped with low efficiency based on comparable concentrations of Hg and U located 90 km downstream.Conclusions
The efficacy of the use of historical maps and detailed fieldwork was demonstrated by identification of unique depositional meso-environments, which are rare in bedrock-confined fluvial systems. The contamination chemostratigraphy of the bar deposits was correlated with the local mining and pollution history and contributed to an understanding of the bar evolution. The approach used in our study may be applicable to other montane rivers with historic ore mining and processing in their basins.3.
Tůmová Štěpánka Hrubešová Diana Vorm Petr Hošek Michal Grygar Tomáš Matys 《Journal of Soils and Sediments》2019,19(4):2020-2033
Journal of Soils and Sediments - River channel sediments have been widely used to trace current and historical pollution in fluvial systems, although they are not the only media employed for that... 相似文献
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Tomáš Grygar Ivo Světlík Lenka Lisá Leona Koptíková Aleš Bajer David S. Wray Vojtěch Ettler Martin Mihaljevič Tereza Nováková Magdaléna Koubová Jan Novák Zdeněk Máčka Mirek Smetana 《CATENA》2010
The floodplain of the Morava River in Strá?nické Pomoraví, south-east Moravia, Czech Republic contains a very valuable record of regional environmental change, which goes back to several thousand years. Its interpretation has been limited by poor stratigraphic correlation and dating of the sediments. We present a geochemical solution to this challenge. We studied 8 outcrops of floodplain deposits from 4 localities along a 6 km long part of the current meander belt of the Morava River in Strá?nické Pomoraví using geochemical proxy analyses, magnetic susceptibility measurements, 14C dating of wood remnants, and sediment micromorphology. The proxy methods are based on elemental analysis (EDXRF) and analysis of the cation exchange capacity of clay minerals; granulometric analyses provided the basis for lithological and facies assignment of the sediments. Our geochemical and mineralogical interpretations have further been tested by microstratigraphically studying the optical properties of the fine fraction. Horizons older than about 3 centuries were 14C dated using wood remnants and the age of deposits from the last century was determined on the base of several proxies reflecting their industrial contamination by heavy metals and magnetic particles. The mean depositional rate over the period from about 1000 to about 1900 AD ranged from 0.2 to 0.6 mm y− 1, depending on the sedimentary facies. The coeval lithological change in the majority of the studied sections indicated a change of the meander belt structure at between ~ 1200 AD and ~ 1600 AD probably as a consequence of changes of channel structure. The alluvial deposition in the 20th century was strongly affected by the river regulation. 相似文献
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The frequency of double ovulation and the chances of twin pregnancy in the mare are presented with reference to the relevant literature. A novel manual technique for reducing the embryo number from two to one is introduced and illustrated by ultrasonographic images. 相似文献
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T. Matys Grygar T. Nováková M. Mihaljevič L. Strnad I. Světlík L. Koptíková L. Lisá R. Brázdil Z. Máčka Z. Stachoň H. Svitavská-Svobodová D.S. Wray 《CATENA》2011
Sediment profiles from the floodplain of Morava River in the Czech Republic have been collected from exposed river banks (4–6 m long sections) and cores (2–4 m deep) and investigated using a set of geochemical proxies validated by granulometry and conventional geochemical analysis, outlined in our previous paper. The work was conducted to evaluate the increase in sedimentation rate during Medieval and modern time periods. Correlation of sediments along the current channel belt allows identification of two most important synchronous changes in the channel structure over the past 1300 years: in the 13th century and at the end of the 16th century. These changes could be related to central European climatic extremes rather than to land cover/land use practises. Analysis of the pollen record in peaty deposits at the floodplain edge allows excluded dramatic deforestation in Medieval times. Maps of the area from the last five centuries revealed direct and indirect signs of past avulsions and clearly show how the original multichannel system was transformed into a single meandering channel in the early 20th century. The extrapolated aggradation rate (net vertical accretion of floodplain fines except for levee sediments) increased from 0.2–0.3 cm/year in 700 AD to 0.3–0.4 cm/year in 2000 AD depending on the grain size of the sediment. This is the smallest yet reported enhancement of siliclastic deposition, although Morava River watershed has been intensively used for agriculture and its land cover has changed in a manner similar to west and central European rivers. 相似文献
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Tereza Novakova Tomas Matys Grygar Ondrej Babek Martin Famera Martin Mihaljevic Ladislav Strnad 《Journal of Soils and Sediments》2013,13(2):460-473
Purpose
Regional contamination of southern Moravia (SE part of the Czech Republic) by trace metals and magnetic particles during the twentieth century was quantified in fluvial sediments of the Morava River. The influence of local pollution sources on regional contamination of the river sediments and the effect of sampling site heterogeneity were studied in sediment profiles with different lithologies.Materials and methods
Hundreds of sediment samples were obtained from regulated channel banks and naturally inundated floodplains and proxy elemental analyses were carried out by energy dispersive X-ray fluorescence spectroscopy (ED XRF) and further calibrated by inductively coupled plasma mass spectrometry (ICP MS). Magnetic susceptibility was determined as a proxy for industrial contamination. The age model for the floodplain sediments was established from 137Cs and 210Pb dating. Trace metal contamination was assessed by establishing the lithological background values from floodplain profiles and calculating enrichment factors (EF) of trace metals (i.e. Pb, Zn, Cu) and magnetic susceptibility for the entire study area.Results and discussion
Channel sediments are unsuitable for the reconstruction of historical regional contamination due to their lithological heterogeneity and the “chaotic” influence of local sources of contamination, as well as the possibility of geochemical mobility of pollutants. On the other hand, sediments from regulated river banks qualitatively reflected the actual, local contamination of the river system.Conclusions
This approach allowed us to distinguish the influence of local sources of contamination by comparison with more spatially averaged contamination signals from distal floodplain profiles. The studied area is weakly contaminated (EF ～1–2), while individual sediment strata from regulated channel banks reflect local sources of contamination and contain up to several times higher concentrations of trace metals. 相似文献8.
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Maria Hojdová Tomáš Navrátil Jan Rohovec Vít Penížek Tomáš Grygar 《Water, air, and soil pollution》2009,196(1-4):89-99
In this paper a novel methodology for estimating the parameters for an extended biokinetic model (Peev, Schönerklee, and De Wever, Water Science and Technology, 2004) of micropollutant removal in wastewater treatment is presented. In particular, the work concentrates on parameter estimation of the micropollutant degradation sub-model by specialised microorganisms in the case when only substrate measurement data are available. We have proven the structural identifiability of the model and have developed a new approach allowing practical identifiability on the basis of multiple substrate degradation curves with different initial concentrations. Experimental and related numerical methods for unambiguous parameter estimation have been developed. Finally, by means of simulated pseudo-experiments we have found convincing indications that the proposed algorithm is stable and yields appropriate parameter estimates even in unfavourable regimes. 相似文献
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