The occurrence on carboniferous coal of anthropogenic origin in the contemporaneous Vistula river sediments near Cracow (Southern Poland)

Carboniferous pit coal is the most important anthropogenic component of the contemporaneous Vistula river gravels and sands with individual fractions containing from 10 to 98 per cent coal fragments. Coal concentration is connected with differences in the bulk density between coal and other gravel components. The lower sediments date from the first half of the nineteenth century when the coal began to appear in large quantities in the Vistula channel. The presence of coal is also an indicator of the depth of channel sediment reworking during floods in the nineteenth and twentieth centuries.     

Distribution of trace metals and Pb isotopes in bottom sediments of the Murucupi River,North Brazil

The Murucupi River belongs to the hydrographic network of the Pará River estuary, at the southern portion of the Amazon River mouth, which consists of a fluvial-marine transitional zone under strong impact of both tidal and fluvial currents. The geochemical results obtained for bottom sediments from the Murucupi River, the Arrozal Channel, and the Pará River indicate a natural variation of Pb, Cr, Cu, Zn, and Ni content among these water ways with no significant anthropogenic influence. According to the threshold effects level (TEL), the contents of trace metals do not offer risk to the local biota. By contrast, the differences in the Pb isotopic composition of sediments in the Murucupi River, the Arrozal Channel, and the Pará River are significant. These isotopic signatures indicate an anthropogenic contribution of Pb in the Murucupi River originating from the domestic effluents of urban centers; industrial waste represented by red mud is not included. These results demonstrate that the Pb isotopic signature is a prospective indicator for future contamination of bottom sediments by trace metals and is useful for identifying contaminants among the possible anthropogenic sources.     

The rare earth element compositions of the Changjiang (Yangtze) and Huanghe (Yellow) river sediments

Thirty-four samples from the Changjiang and Huanghe were analyzed to characterize their rare earth element (REE) compositions. Although REE concentrations in the Changjiang sediments are higher than those of the Huanghe sediments, the former are less variable. Bulk samples and acid-leachable fractions have convex REE patterns and middle REE enrichments relative to upper continental crust, whereas flat patterns are present in the residual fractions. Source rock composition is the primary control on REE composition, and weathering processes play a minor role. Grain size exerts some influence on REE composition, as demonstrated by the higher REE contents of clay minerals in sediments from both rivers. Heavy minerals contribute about 10-20% of the total REE in the sediments. Apatite is rare in the river sediments, and contributes less than 2% of the REE content, but other heavy minerals such as sphene, allanite and zircon are important reservoirs of residual REE fractions. The Fe-Mn oxides phase accounts for about 14% of bulk REE content in the Changjiang sediments, which could be one of the more important factors controlling REE fractionation in the leachable fraction.     

Preliminary study on the mineral magnetic properties of sediments from Kůlna Cave (Moravian Karst), Czech Republic

Summary Magnetic property variations in marine, lacustrine and loess-paleosol sequences have proved to be useful proxies in climate change studies. However in order to correctly interpret the record of the magnetic property variations it is absolutely necessary to have a good understanding of the cause of the observed variations. Most of the ambiguity in loess-paleosol studies is in distinguishing the role of pedogenesis from other climatic factors. Studying the mineral magnetic properties of the protected cave sediments which have not undergone pedogenesis allows us to determine the degree to which detrital input is climatically driven. These results will help us better understand the variations observed in the surficial loess-paleosol sequences. This study reports mineral magnetic data collected from entrance facies sediments deposited during the early Wurmian glacial stage in the Kůlna Cave. The entrance facies sediments consist of loess-like silts with varying amount of talus. The magnetic susceptibility record from these sediments shows higher values in layers originating in colder climates which is different to that commonly observed in surficial loess deposits. Higher values of magnetic susceptibility in Kůlna sediments are probably due to higher concentrations of ferromagnetic minerals (magnetite and maghemite) and due to an increased proportion of superparamagnetic grains. The magnetic mineralogy and the grainsize distribution (grains larger than superparamagnetic) appear not to change throughout the studied profiles. Higher magnetic susceptibility accompanied by an increase in the superparamagnetic fraction observed in the sediments deposited during colder periods can be explained by an increased input from a pedogenic source when the vegetation cover was reduced and the erosion rate increased.     

Periodicity of Mining and Induced Seismicity in the Mayrau Mine,Czech Republic

Mine excavation in deep black-coal Mayrau Mine, Czech Rep., has a pronounced 7-day periodicity due to the absence of mining during weekend days. Also seismicity induced by mining exhibits some features of the 7-day period. It was found that the number of events generally depends on the intensity of mining, while the analogous dependences of mean energy per event and the total energy per day are weaker. Selective analysis showed that total extent of exploitation has more influences on the seismicity than coining of drifts. The statistical parameters of seismicity (b-value) do not change in accordance with the day of the week.     

The River Arno catchment,northern Tuscany: chemistry of waters and sediments from the River Elsa and River Era sub‐basins,and sulphur and oxygen isotopes of aqueous sulphate

Within the hydrologic balance of the River Arno catchment (northern Tuscany), the Rivers Elsa and Era are important tributaries entering the main river from the left bank in the lower part of the watershed. Waters and bed sediments were sampled in June 2000 during low discharges in the Rivers Elsa and Era, as well as in major tributary streams. Water samples were analysed for major chemistry and sulphur isotope composition of sulphate, and sediment samples were analysed for major composition and selected trace elements of environmental concern (Zn, Cu, Pb, Cr and Ni). The main results for the waters are: (1) Na and Cl in solution show consistent downstream positive trends in the main rivers, thus supporting progressive contributions of anthropogenic salts; the highest concentration values are observed in tributaries; (2) as shown by sulphur isotopes, sulphate in solution is mainly controlled by dissolution of evaporites (Elsa basin) or oxidation of reduced organic/biogenic sulphur (Era basin), with anthropogenic contributions in most streams not higher than 10% in both the basins. A δ³⁴S signature in the range ?2 to +3‰ is estimated for pollutant sulphate in the basins studied. The main results for the sediments are: (1) major chemistry is essentially controlled by the lithotypes drained by the waters; (2) pollution by heavy metals does not reach high levels; (3) compared with local fine‐grained rocks, copper is more frequently anomalous, whereas lead and zinc show only occasional anomalies; (4) local high concentrations of chromium and nickel can be attributed to upstream occurrences of ophiolites. Copyright © 2006 John Wiley & Sons, Ltd.     

Optical dating of Holocene lake sediments: Elimination of the feldspar component in fine silt quartz samples

Optically stimulated luminescence of fine silt quartz was investigated to establish chronologies for lake sediments from the British Isles. Feldspar contamination and its potential effects on equivalent dose (D_e) determination were examined. A new feldspar contamination test based on the thermal quenching of quartz OSL and thermal assistance of feldspar OSL identified feldspar contamination in samples being treated for 20 min in 20% hydrofluoric acid. Feldspar component monitoring based on the post-IR OSL/OSL ratio was not sufficiently sensitive to monitor a feldspar component, but is a good indicator whether a standard SAR procedure can be applied successfully, despite the presence of feldspar. Based on these results we used a modified SAR protocol including a 100 s IRSL stimulation at 50 °C before OSL readout. This protocol could overcome any malign effects of feldspar even for a feldspar bearing polymineral sub-sample.     

Variations in texture of beach sediments in the vicinity of the Tirumalairajanar river mouth of India

The distribution of grain size parameters along 11 km stretch of the beach sediments between Karikal and Nagore,reveals that the mean grain size exhibits a marked decreasing trend on either side of the mouth of the Tirumalairajanar River which flow from west to east.The sediments are mainly of medium to coarse grained,moderately sorted,near-symmetrical skewed to fine skewed and leptokurtic to mesokurtic in nature.Interrelationship of various parameters shows bimodal nature of sediments having dominance of medium to coarse sand.The major part of the sediment fall in a coarse to fine grained category(sand and silt).Based on the CM(Coarser one percentile value in micron) pattern,the sediment fall in rolling and suspension field.These factors includes the sediments discharged from the river mixes with offshore sediments and with the sediments eroded from a source rock.The effect of wave sorting, and the northward drifting of sediments by littoral current are understandable.Results indicate that the Tirumalairajanar River is the most important source for modern sediments in the study area.The agitation by waves is an important sorting mechanism in the study area,and the net sediment transport in the study area is northward.The findings are based on the grain sizes and also corroborated by shortterm observations of the beach sediment dynamics and transport during the monsoon and summer seasons between Karaikal and Nagore region.     

The unique environment of the most acidified permanently meromictic lake in the Czech Republic

Changes in the water properties and biological characteristics of the highly acidic Hromnice Lake (Western Bohemia) were investigated. This 110-year-old lake, formed as a consequence of the mining of pyritic shales, is permanently meromictic. Two chemoclines separate an extremely acidic (pH ～ 2.6) mixolimnion from a metal-rich anoxic monimolimnion. The absence of spring mixolimnetic turnover due to ice melting and very slow heat propagation through the chemocline with a 6-month delay were observed. Extreme mixolimnetic oxygen maxima (up to 31 mg l^?1) in phosphorus-rich lake (PO₄^3? up to 1.6 mg l^?1) well correlated with outbursts of phytoplankton. Phytoplankton consist of several acido-tolerant species of the genera Coccomyxa, Lepocinclis, Chlamydomonas and Chromulina. Surface phytoplankton biomass expressed as chlorophyll-a varies from 2 to 140 μg l^?1. Multicellular zooplankton are almost absent with the exception of Cephalodella acidophila, a small rotifer occurring in low numbers. Large red larvae of the midge Chironomus gr. plumosus were found at the bottom close to the shore, with larvulae in the open water. Developmental stages (protonemata) of a moss, resembling filamentous algae, dwell in the otherwise plant-free littoral zone.     

Source and distribution of lead in the surface sediments from the South China Sea as derived from Pb isotopes

Rapid economic development in East Asian countries has inevitably resulted in environmental degradation in the surrounding seas, and concern for the environment and its protection against pollutants is increasing. Identification of sources of contaminants and evaluation of current environmental status are essential to environmental pollution management, but relatively little has been done in the South China Sea (SCS). In order to investigate the abundance, distribution, and sources of Pb within the SCS, stable Pb isotopes and their ratios were employed to assess the contamination status and to differentiate between natural and anthropogenic origins of Pb in the surface sediments. The total Pb concentrations in sediments varied from 4.18 to 58.7 mg kg⁻¹, with an average concentration of 23.6 ± 8.9 mg kg⁻¹. The observed Pb isotope ratios varied from 18.039 to 19.211 for ²⁰⁶Pb/²⁰⁴Pb, 15.228 to 16.080 for ²⁰⁷Pb/²⁰⁴Pb, 37.786 to 39.951 for ²⁰⁸Pb/²⁰⁴Pb, 1.176 to 1.235 for ²⁰⁶Pb/²⁰⁷Pb, and 2.468 to 2.521 for ²⁰⁸Pb/²⁰⁷Pb. The majority of these ratios are similar to those reported for natural detrital materials. Combined with Pb enrichment factor values, our results show that Pb found within most of the SCS sediments was mainly derived from natural sources, and that there was not significant Pb pollution from anthropogenic sources before 1998. Further studies are needed to reconstruct deposition history and for trend analysis.     

Strontium isotope identification of water mixing and recharge sources in a river system (Oder River,central Europe): A quantitative approach

This study uses Sr isotope composition (⁸⁷Sr/⁸⁶Sr) and Sr content of waters of the Oder, one of the largest rivers in central Europe, to fingerprint natural and anthropogenic contributions to its Sr budget and to evaluate water mixing processes in its hydrological system. It also demonstrates a simple method of quantifying natural and anthropogenic Sr inputs in the watershed. The method has potential for environmental and archaeological research because past Sr geochemistry of river water can easily be reconstructed. For the first time, a catchment‐scale impact of anthropogenic sources on the Sr budget of a middle‐size river is shown in a quantitative way. The water of the Oder is characterized by a relatively uniform Sr isotope composition, from 0.7100 to 0.7108, contrasting with strong variations in Sr concentration, from 0.25 to 1.27 mg/L. There is a general seasonal trend in variability, with waters becoming more radiogenic and dilute with respect to the Sr in the spring time. This Sr systematics differs significantly from the Sr budgets of the majority of the Oder tributaries that exhibit more radiogenic composition and systematically lower Sr concentrations. A mixing scenario in the Oder involves Sr contribution from four principal water sources: (a) shallow ground waters with Sr derived from near‐surface weathering of silicates, (b) moderately radiogenic mine waters from the Upper Silesian Coal Basin, (c) unradiogenic mine waters from the Permian sequence of the copper district, and (d) unradiogenic ground waters from shallow‐seated Palaeogene, Neogene, and Mesozoic aquifers. The Sr budget of the Oder is primarily controlled by inputs of dissolved Sr from anthropogenic sources, which overprint the natural background, controlled by geology. Thus, about 47.5% of Sr originates from agriculture, industrial, and municipal additions, 31.5% from mine water inputs, and only 21% from natural sources, that is, rock weathering and atmospheric precipitation. Reconstruction of the past Sr chemistry of the Oder reveals that its present‐day Sr isotope composition is temporary and significantly different from that of the preindustrial times.     

Water quality in rural areas of the Czech Republic: Key study Slapanka River catchment

The article evaluates the water quality in rural areas in the Czech part of Labe River catchment using the example of Slapanka River catchment. This river drains a typical landscape of Ceskomoravska Highland. Water quality in rural areas is still very low and the attention is paid to organic substances and nutrients. Increased amount of them in streams is caused mainly by agriculture and production of municipal wastewater resulting in increased eutrophication. A significant part of the article consists in the evaluation of point and non-point sources of water pollution. Identifying the type of the pollution source is helped by regression analysis using data from the public monitoring network. Eleven sampling sites were selected for evaluating the water quality. Physical and chemical analyses were made 12 times during the field monitoring in the years 2001–2003.In long-term development water quality has improved in all monitored parameters during the last 15 years. Least significant improvement has been found with the concentration of nitrate nitrogen. The water quality within the whole catchment area still remains low.To reduce the influence of pollution sources, we recommend the sanitation of diffuse sources of pollution from small settlements with less than 2000 inhabitants, and a successive change from agricultural management and intensive mass production to extensive ways, especially in mountain and sub-mountain areas.     

Distribution of rare earth elements in marine sediments from the Strait of Sicily (western Mediterranean Sea): evidence of phosphogypsum waste contamination

Concentrations of rare earth elements (REE), Y, Th and Sc were recently determined in marine sediments collected using a box corer along two onshore-offshore transects located in the Strait of Sicily (Mediterranean Sea). The REE + Y were enriched in offshore fine-grained sediments where clay minerals are abundant, whereas the REE + Y contents were lower in onshore coarse-grained sediments with high carbonate fractions. Considering this distribution trend, the onshore sediments in front of the southwestern Sicilian coast represent an anomaly with high REE + Y concentrations (mean value 163.4 μg g⁻¹) associated to high Th concentrations (mean value 7.9 μg g⁻¹). Plot of shale-normalized REE + Y data of these coastal sediments showed Middle REE enrichments relative to Light REE and Heavy REE, manifested by a convexity around Sm-Gd-Eu elements. These anomalies in the fractionation patterns of the coastal sediments were attributed to phosphogypsum-contaminated effluents from an industrial plant, located in the southern Sicilian coast.     

Evaluation of metal contamination in coastal sediments of the Bay of Bengal, India: geochemical and statistical approaches

Surface sediment samples collected from the inner shelf region of the Bay of Bengal, were analysed for the major elements and total and acetic acid available trace elements (Al, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, P, Pb, Si, Zn) to evaluate geochemical processes influencing their distribution. Major elemental analysis showed that the sediments had high concentrations of Si and relatively low concentrations of Al and Fe. Both major elemental and trace metal concentrations indicated that the sediments represent weathered products of granite and charnockite. Normalization of metals to Al indicated relatively high enrichment factors for Pb, Cd, Zn and Cr. The higher proportions of nondetrital Pb (66%), Cd (41%) and Co (28%) reveal metal contamination due to anthropogenic inputs. Factor analysis (FA) identified six possible types of sedimentological and geochemical associations. The dominant factor accounting for 26.9% of the total variance identifies an anthropogenic input and accumulation of nondetrital Cd, Co, Cr, Ni and Pb. Association of these metals with CaCO3 reveals that shell fragments in the surface sediments are likely act as a carrier phase for nondetrital metals. The results are discussed in the context of the sources and pathways of elements in the Bay of Bengal.     

Chemical remobilization of contaminant metals within floodplain sediments in an incising river system: implications for dating and chemostratigraphy

Metals such as Pb, Zn, Cd and Cu from historical mining activity have been used as stratigraphic markers for dating and provenancing vertically accreted, fine-grained floodplain overbank deposits. This study presents evidence for chemical remobilization of these metals within overbank sediments in the Tyne basin, UK. The evidence includes: breakdown of metal-bearing minerals (sulphides, carbonates, iron and manganese oxyhydroxides); shifts of chemical fractions within zones of relatively low pH towards more soluble and reactive phases; and accumulation of secondary iron and manganese oxyhydroxides at levels related to fluctuating water-table levels or to the breakdown of organic matter. All of this suggests that fine, centimetre-scale, chemostratigraphy using metal concentrations and ratios is unlikely to provide reliable data in river systems that have experienced, or are experiencing, major changes in water-table levels, or pedogenesis. Coarse tens of centimetre- to metre-scale, chemostratigraphy, when applied with caution, may still provide a means of delineating contaminated units. © 1998 John Wiley & Sons, Ltd.     

Particle size characteristics of suspended and bed sediments in the rhône river

Ten large volume water samples were taken from the Rhône River (Switzerland-France) in November, 1989 for recovery of total suspended sediment by continuous flow centrifugation. the samples were freeze-dried and analysed for particle size, organic carbon, total nitrogen, and carbonate. for comparative purposes, four bed sediments collected in July, 1989 are also described. the Rhône can be subdivided into three sections on the basis of the origins of the water. the first section is the Upper Rhône River draining into Lake Geneva. Waters are derived from glaciers, with low temperature and conductivity and high turbidity. Suspended sediment is coarse, has a bimodal distribution, and is low in both organic matter and carbonate. the second reach is from Lake Geneva to the confluence with the Saône at Lyon and has warmer water with higher conductivity and very low turbidity. Suspended sediment is higher in organic matter, with high carbonate originating from the lake. the final section is from Lyon to Arles, with warmer water and higher conductivity and turbidity due to modification by the Saône. Sediment is rich in organic matter, which May, account for an observed decline in oxygen in the river waters downstream from Lyon. Carbonate in these sediments also decreases due to increased turbidity from the Saône. Suspended sediments other than from the Upper Rhône show a remarkable consistency in grain size, predominantly in the fine silts (mode 9-11 μm). This consistency indicates a high degree of suitability for geochemical analysis. Bed sediments were bimodal throughout, with a dominant coarse population in two out of the four samples. Grain size statistical parameters could be easily explained by application of the theory of mixing of two major populations in the sand size (bed traction load) and the fine silt/clay size (suspended sediment load).     

新疆孔雀河北岸72-51 ka BP湖相沉积物中粘土矿物特征

对新疆孔雀河北岸LX02剖面湖相沉积物开展光释光和粘土矿物样品X射线衍射分析,根据样品中的粘土矿物成分及质量分数对本区古气候演化进行了探讨.结果显示,该剖面湖相沉积自72 ka BP延续到51 ka BP.这期间,研究区粘土矿物以伊利石占绝对优势(56%~64%,平均为61%),其它粘土矿物有绿泥石(18%~26%,平均为22%)、高岭石(7%~12%,平均为8%)和伊/蒙混层(5%~15%,平均为9%),这与塔里木盆地粘土矿物组成颇为一致.具体来说,72.4—66.8 ka BP,伊利石和绿泥石含量之和较高,同时绿泥石含量较高,对于高岭石而言,除了一个样品外,其它样品的平均值较低,伊/蒙混层含量较低,指示该时段为冷干气候环境;66.8—56.1 ka BP,伊利石和绿泥石含量之和最低,同时绿泥石含量亦最低,高岭石、伊/蒙混层含量较高,指示该时段为暖湿气候环境;56.1—51.0 ka BP,伊利石和绿泥石含量之和增大,同时绿泥石含量亦增大,高岭石、伊/蒙混层含量较低,指示该时段为较冷干气候环境.这与孢粉植物群、地球化学元素含量及其主成分F1和粒度、色度及碳酸盐主成分F1'所反映的古气候特征及其变化一致,亦与柴达木盆地东部介形类丰度特征研究、柴达木盆地东部古湖泊高湖面光释光年代学研究、北京平原区有机碳同位素研究等结果吻合较好.研究表明塔里木盆地东部晚更新世气候仍以暖湿-冷干气候变化模式为主.     

Morphological effects of different channel‐forming discharges in a gravel‐bed river

The study analyses the morphological response of a gravel‐bed river to discharges of different magnitude (from moderate events that occur several times a year to a 12‐year flood) and so defines the range of formative discharges for single morphological units (channels, bars, islands) and a range of magnitude of morphological activity from the threshold discharges for gravel transport and minor bar modification up to flows causing major morphological changes. The study was conducted on the Tagliamento River, a large gravel‐bed river in north‐eastern Italy, using two different methods, analysis of aerial photographs and field observation of painted gravel particles. The available photographs (five flights from August 1997 to November 2002) and the two commissioned flights (June 2006 and April 2007) do not define periods with a single flood event, but the intervals are short enough (11 to 22 months) to have a limited number of flood events in each case. The fieldwork, which involved cross‐section survey, grain‐size analysis and observation of painted sediments, complemented the aerial surveys by allowing analysis of channel response to single flood events. Substantial morphological changes (e.g. bank erosion of several tens of metres up to more than 100 m) associated with flood events with a recurrence interval between 1·1 year and 12 years have been documented. Multiple forming discharges were defined based on the activity of different morphological units. Discharges equal to 20–50% of the bankfull discharge are formative for the channels, whereas the bankfull discharge (1·1 year flood in this case of the Tagliamento River) is formative for low bars. Larger floods, but still relatively frequent (with a recurrence interval less than five years), are required for full gravel transport on high bars and significant morphological changes of islands. Copyright © 2009 John Wiley & Sons, Ltd.