100 Years of Sediment Accumulation History of Organic Halogens and Heavy Metals in Recipient and Nonrecipient Lakes of Pulping Industry in Finland

The study deals with the spatio-temporal distribution of heavy metals in the sediments of Chagan lake, Northeast China. The pollution history of heavy metals is studied simultaneously through the 210Pb dating method by analyzing the characteristic of As, Hg, Cd, Cr, Ni, Cu, Pb, and Zn concentration-depth profiles. The potential ecological risk index (RI) and geo-accumulation index (Igeo) were used to evaluate the contamination degree. Principal component analysis (PCA), based on the logarithmic transformation and isometric log-ratio (ilr) transformed data, was applied with the aim of identifying the sources of heavy metals. The element concentrations show that the heavy metals are enriched in the surface sediment and sediment core with a varying degree, which is higher in the surficial residue. The results of Igeo indicate that the Cd and Hg in the surface sediment have reached a slightly contaminated level while other elements, uncontaminated. The results of RI show that the study area can be classified as an area with moderate ecological risk in which Cd and Hg mostly contribute to the overall risk. For the sediment core, the 210Pb dating results accurately reflect the sedimentary history over 153 years. From two evaluation indices (RI and Igeo) calculated by element concentration, there is no contamination, and the potential ecological risk is low during this period. The comparative study between raw and ilr transformed data shows that the closure effect of the raw data can be eliminated by ilr transformation. After that, the components obtained by robust principal component analysis (RPCA) are more representative than those obtained by PCA, both based on ilr transformed dataset, after eliminating the influence of outliers. Based on ilr transformed data with RPCA, three primary sources could be inferred: Cr, Ni, As, Zn, and Cu are mainly derived from natural sources; the main source of Cd and Hg are associated with agricultural activities and energy development; as for Pb, it originated from traffic and coal-burning activities, which is consistent with the fact that the development of tourism, fishery, and agriculture industries has led to the continuous increasing levels of anthropogenic Pb in Chagan Lake. The summarized results and conclusions will undoubtedly enhance the governmental awareness of heavy metal pollution and facilitate appropriate pollution control measures in Chagan Lake.

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Lake-level variability in Salar de Coipasa, Bolivia during the past ∼40,000 yr

Quaternary Research ◽

10.1017/qua.2018.108 ◽

2018 ◽

Vol 91 (2) ◽

pp. 881-891 ◽

Cited By ~ 4

Author(s):

J. Andrew Nunnery ◽

Sherilyn C. Fritz ◽

Paul A. Baker ◽

Wout Salenbien

Keyword(s):

Lake Level ◽

Sediment Accumulation ◽

Geochemical Data ◽

South American ◽

Climate History ◽

Oxygen Isotope Stage ◽

The Past ◽

History Of ◽

Diatom Stratigraphy ◽

The Last Glacial

AbstractVarious paleoclimatic records have been used to reconstruct the hydrologic history of the Altiplano, relating this history to past variability of the South American summer monsoon. Prior studies of the southern Altiplano, the location of the world’s largest salt flat, the Salar de Uyuni, and its neighbor, the Salar de Coipasa, generally agree in their reconstructions of the climate history of the past ∼24 ka. Some studies, however, have highly divergent climatic records and interpretations of earlier periods. In this study, lake-level variation was reconstructed from a ∼14-m-long sediment core from the Salar de Coipasa. These sediments span the last ∼40 ka. Lacustrine sediment accumulation was apparently continuous in the basin from ∼40 to 6 ka, with dry or very shallow conditions afterward. The fossil diatom stratigraphy and geochemical data (δ13C, δ15N, %Ca, C/N) indicate fluctuations in lake level from shallow to moderately deep, with the deepest conditions correlative with the Heinrich-1 and Younger Dryas events. The stratigraphy shows a continuous lake of variable depth and salinity during the last glacial maximum and latter stages of Marine Oxygen Isotope Stage 3 and is consistent with environmental inferences and the original chronology of a drill core from Salar de Uyuni.

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SEAMUS (v1.0): a Δ<sup>14</sup>C-enabled, single-specimen sediment accumulation simulator

10.5194/gmd-2019-155 ◽

2019 ◽

Author(s):

Bryan C. Lougheed

Keyword(s):

Sediment Core ◽

Accumulation Rate ◽

Sediment Accumulation ◽

Species Abundance ◽

Depth Interval ◽

Single Specimen ◽

14C Dating ◽

Deep Sea Sediment ◽

Wide Range ◽

History Of

Abstract. The systematic bioturbation of single particles (such as foraminifera) within deep-sea sediment archives leads to the apparent smoothing of any temporal signal as record by the downcore, discrete-depth mean signal. This smoothing is the result of the systematic mixing of particles from a wide range of depositional ages into the same discrete depth interval. Previous sediment models that simulate bioturbation have specifically produced an output in the form of a downcore, discrete-depth mean signal. Palaeoceanographers analysing the distribution of single foraminifera specimens from sediment core intervals would be assisted by a model that specifically evaluates the effect of bioturbation upon single specimen populations. Taking advantage of recent increases in computer memory, the single-specimen SEdiment AccuMUlation Simulator (SEAMUS) was created in Matlab, whereby large arrays of single specimens are simulated. This simulation allows researchers to analyse the post-bioturbation age heterogeneity of single specimens contained within discrete-depth sediment core intervals, and how this heterogeneity is influenced by changes in sediment accumulation rate (SAR), bioturbation depth (BD) and species abundance. The simulation also assigns a realistic 14C activity to each specimen, by considering the dynamic Δ14C history of the Earth and temporal changes in reservoir age. This approach allows for the quantification of possible significant artefacts arising when 14C dating multi-specimen samples with heterogeneous 14C activity. Users may also assign additional desired carrier signals to specimens (e.g., stable isotopes, trace elements, temperature, etc.) and consider a second species with an independent abundance. Finally, the model can simulate a virtual palaeoceanographer by randomly picking whole specimens (whereby the user can set the percentage of older, broken specimens) of a prescribed sample size from discrete depths, after which virtual laboratory 14C dating and 14C calibration is carried out within the model.

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The history of airborne lead and other heavy metals as revealed from sediments of Lake Vähä-Pitkusta, SW Finland

Bulletin of the Geological Society of Finland ◽

10.17741/bgsf/76.1-2.002 ◽

2004 ◽

Vol 76 (1-2) ◽

pp. 19-30 ◽

Cited By ~ 4

Author(s):

A. Hakala ◽

V.-P. Salonen

Keyword(s):

Heavy Metals ◽

History Of ◽

Airborne Lead

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CONCENTRATION OF HEAVY METALS IN WATER FLOWS IN THE AREA OF UNALSKY TAILING DUMP AND ARDON RIVER

South of Russia ecology development ◽

10.18470/1992-1098-2018-2-113-122 ◽

2018 ◽

Vol 13 (2) ◽

pp. 113-122 ◽

Cited By ~ 1

Author(s):

Dzerassa N. Chigoeva ◽

Inna Z. Kamanina ◽

Svetlana P. Kaplina

Keyword(s):

Heavy Metals ◽

Production Capacity ◽

Chemical Pollution ◽

Environmental Disaster ◽

Tailing Dump ◽

Maximum Permissible Concentrations ◽

History Of ◽

Lead Zinc ◽

Domestic Use ◽

Cadmium Lead

The long history of development of deposits of lead-zinc ores of the Sadonsky mining region led to the formation of extensive halos of chemical pollution of surface watercourses. Aim. The aim of this study is to monitor surface watercourses in the area of the Unalsky tailing dumps and the Kholst deposit by points of sampling of 1992-2004. Sampling was conducted in the summer of 2016. Methods. The content of heavy metals of 2 and 3 hazard classes (Pb, Cd, Ni, Zn and Cu) was studied by atomic absorption. The contribution of the Unaldon River and Unalsky tailing dump to the pollution of the Ardon River. Results. The highest content of cadmium, lead and zinc, significantly exceeding the maximum permissible concentrations (MPC) in the water bodies of cultural and domestic use is found in the Ardon River down from the Unalsky tailing dump. The flow of heavy metals into the Unaldon River with adit waters compared with the observation period of 1992-2004 decreased noticeably. In conditions of a reduction in the production capacity of mining and processing enterprises, the leaching of heavy metals from mountain dumps and excavations make an insignificant contribution to the pollution of the Ardon River in comparison with the Unalsky tailing dump. Conclusion. The state of the Ardon River down from the discharge from the tailing dump corresponds to the "environmental disaster" category. The condition of the rivers Mayramdon and Unaldon according to the content of heavy metals corresponds to a "relatively satisfactory" type.

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