scholarly journals The cretaceous-tertiary boundary Fiskeler at Stevns Klint, Denmark: The geochemistry of the major trace metals

2001 ◽  
Vol 66 (10) ◽  
pp. 647-670 ◽  
Author(s):  
Pavle Premovic ◽  
Nikola Nikolic ◽  
Mirjana Pavlovic ◽  
Bratislav Todorovic ◽  
Dragan Djordjevic ◽  
...  

Trace metals in the four discrete layers of the Cretaceous-Tertiary boundary (Fiskeler) at Stevns Klint (Denmark) are relatively well studied, yet much remains to be learned about them. Therefore, an integrated study of the trace (meteoritic Ir, partly meteoritic Cr/Ni/Co/Au and terrestrial Zn/Cu/La/Ce/Nd/Sm/Eu/Tb/Yb/Ta/Th) metals in the basal black marl of Fiskeler and in its (carbonate, HCl-soluble, smectite, HCl-insoluble, silicate and kerogen) fractions was undertaken. The mineralogy of the marl is comparatively simple, authigenic calcite (mainly derived from planktonic marine algae: coccoliths), detrital Mg-smectite and quartz being the principal components, with lesser amounts of kerogen, Fe3+-oxides, pyrite, ilite and feldspar. Selective leaching procedures were used to establish geochemical associations and specific mineralogical locations of the trace metals. The results identified the main locations of the major trace metals (Cr/Ni/Co/Zn/Cu/Ir/Au). They occur mainly in the smectite and, to a lesser extent, in the biogenic calcite (Ni/Co/Zn) and kerogen (Ir/Au). The trace metal data are in accordance with the hypothesis that substantial proportions of Cr/Ni/Co/Zn/Cu/Ir/Au were probably contained in the detrital smectite arriving at the site of the deposition. In a general discussion of the results, a geochemical model describing the incorporation of trace metals in the smectite is presented, based on the weathering/trasport of the clay by (impact-induced) acid surface waters and the adsorption of trace metal ions by the smectite particles/colloids in the acidic solution of nearby oxic soil. The distribution/enrichment patterns of Cr/Ni/Co/Zn of the basal black marl and higher Fiskeler layers indicate, on the other hand, that notable proportions of these metals were incorporated into the smectite structure during the formation of the clay. The trace metal data are also considered in light of previously published paleoecological and geochemical information for Fiskeler. It is proposed, for example, that the local (impact-induced) superacid rainfall and wildfires played an important role in providing appropriate humics (i.e. appropriate organics of decaying land green plants) having porphyrin stuctures for the formation of kerogen (enriched with Cu2+-porphyrins). In addition, it has been suggested that the biogenic calcite with high Ni is probably a product of the metabolic uptake of boundary seawater (enriched with this metal) by the coccoliths. The metal enrichment of the seawater was created by a sudden and high influx of (apparently mainly meteoritic) Ni: airborne and laterally redeposited (by the acid surface/river waters) from a nearby soil. Lastly, the lateral distribution of kerogen (enriched withCu2+-porpyhyrins) supports an earlier interpretation presented by Hultenberg1,2 that the alleged (Nye Kl?v/Dania) boundaries in northwestern Denmark represent erosion and subsequent redeposition of Fiskeler in eastern Denmark.

2019 ◽  
Author(s):  
Laura-Hélèna Rivellini ◽  
Max G. Adam ◽  
Nethmi Kasthuriarachchi ◽  
Alex K. Y. Lee

Abstract. Understanding sources and atmospheric processes that can influence the physio-chemical properties of carbonaceous aerosols are essential to evaluate their impacts on air quality and climate. However, resolving the sources, emission characteristics and aging processes of carbonaceous aerosols in complex urban environments remain challenging. In this work, a soot-particle aerosol mass spectrometer (SP-AMS) was deployed to characterize organic aerosols (OA), refractory BC (rBC) and trace metals in Singapore, a highly urbanized city with multiple local and regional air pollution sources in the tropical region. rBC (C1+–C9+) fragments and trace metals ions (K+, Na+, Ni+, V+ and Rb+) were integrated into our positive matrix factorization of OA. Two types of fossil fuel combustion-related OA with different degree of oxygenation were identified. This work provides evidence that over 90 % of rBC was originated from local combustion sources with ~ 30 % of them associated with the fresh secondary organic aerosol (SOA) produced under the influences of industrial emissions during daytime. The results also show that ~ 43 % of the total rBC was emitted from local traffic, and the rest of rBC fraction due to multiple sources, including vehicular, shipping and industrial emissions, being not fully resolved. There was only a weak association between the cooking-related OA component and rBC. Although there was no observable biomass burning episode during the sampling period, tracers for biomass burning, K+ and Rb+, were mainly associated with the more-oxidized oxygenated OA component (~ 32 % of the total OA), indicating significant contributions of regional biomass burning emissions to this aged OA component. Furthermore, the aerosol pollutants transported from the industrial area and shipping ports gave higher C1+/C3+ and V+/Ni+ ratios than those associated with traffic and biomass burning. The observed association between Na+ and rBC suggests that the contribution of anthropogenic emissions to total particulate sodium should not be ignored in coastal urban environments. Overall, this work demonstrates that rBC fragments and trace metal ions can improve our understanding on the sources, emissions characteristics and aging history of carbonaceous aerosol (OA and rBC) in this type of complex urban environments.


2020 ◽  
Author(s):  
Laure Gandois ◽  
Alison M. Hoyt ◽  
Stéphane Mounier ◽  
Gaël Le Roux ◽  
Charles F. Harvey ◽  
...  

<p>Worldwide, peatlands are important sources of dissolved organic matter (DOM) and trace metals (TM) to surface waters and these fluxes may increase with peatland degradation. In Southeast Asia, tropical peatlands are being rapidly deforested and drained. The black rivers draining these peatland areas have high concentrations of DOM. However, the fate of this fluvial carbon export is uncertain, and its role as a trace metal carrier has never been investigated. This work aims to address these gaps in our understanding of tropical peatland DOM and associated elements in the context of degraded tropical peatlands of Indonesian Borneo. We quantified dissolved organic carbon and trace metals concentrations in the dissolved, fine colloidal and coarse colloidal fractions and determined the characteristics (optical and isotopic) of the peatland-derived DOM as it drains from peatland canals, flows along black river and eventually mixes with the Kapuas Kecil River before meeting the ocean near the city of Pontianak in West Kalimantan, Indonesia. Black rivers draining degraded peatlands show significantly higher concentrations of Al, Fe, Pb, As, Ni, and Cd, compared the white river. A strong association is observed between DOM, Fe, As, Cd and Zn in the dissolved and fine colloid fraction, while Al is associated to Pb and Ni and present in a higher proportion in the coarse colloidal fraction. We additionally measured the isotopic composition of lead released from degraded tropical peatlands for the first time and show that Pb originates from anthropogenic atmospheric deposition. Degraded tropical peatlands are important sources of DOM and trace metals to rivers and a secondary source of atmospherically deposited contaminants.</p>


Author(s):  
James S. Webber

INTRODUCTION“Acid rain” and “acid deposition” are terms no longer confined to the lexicon of atmospheric scientists and 1imnologists. Public awareness of and concern over this phenomenon, particularly as it affects acid-sensitive regions of North America, have increased dramatically in the last five years. Temperate ecosystems are suffering from decreased pH caused by acid deposition. Human health may be directly affected by respirable sulfates and by the increased solubility of toxic trace metals in acidified waters. Even man's monuments are deteriorating as airborne acids etch metal and stone features.Sulfates account for about two thirds of airborne acids with wet and dry deposition contributing equally to acids reaching surface waters or ground. The industrial Midwest is widely assumed to be the source of most sulfates reaching the acid-sensitive Northeast since S02 emitted as a byproduct of coal combustion in the Midwest dwarfs S02 emitted from all sources in the Northeast.


2020 ◽  
Vol 32 (1) ◽  
Author(s):  
Mulatu Yohannes Nanusha ◽  
Martin Krauss ◽  
Carina D. Schönsee ◽  
Barbara F. Günthardt ◽  
Thomas D. Bucheli ◽  
...  

Abstract Background Substantial efforts have been made to monitor potentially hazardous anthropogenic contaminants in surface waters while for plant secondary metabolites (PSMs) almost no data on occurrence in the water cycle are available. These metabolites enter river waters through various pathways such as leaching, surface run-off and rain sewers or input of litter from vegetation and might add to the biological activity of the chemical mixture. To reduce this data gap, we conducted a LC–HRMS target screening in river waters from two different catchments for 150 plant metabolites which were selected from a larger database considering their expected abundance in the vegetation, their potential mobility, persistence and toxicity in the water cycle and commercial availability of standards. Results The screening revealed the presence of 12 out of 150 possibly toxic PSMs including coumarins (bergapten, scopoletin, fraxidin, esculetin and psoralen), a flavonoid (formononetin) and alkaloids (lycorine and narciclasine). The compounds narciclasine and lycorine were detected at concentrations up to 3 µg/L while esculetin and fraxidin occurred at concentrations above 1 µg/L. Nine compounds occurred at concentrations above 0.1 µg/L, the Threshold for Toxicological Concern (TTC) for non-genotoxic and non-endocrine disrupting chemicals in drinking water. Conclusions Our study provides an overview of potentially biologically active PSMs in surface waters and recommends their consideration in monitoring and risk assessment of water resources. This is currently hampered by a lack of effect data including toxicity to aquatic organisms, endocrine disruption and genotoxicity and demands for involvement of these compounds in biotesting.


2021 ◽  
Vol 1 (1) ◽  
Author(s):  
Roxana T. Shafiee ◽  
Poppy J. Diver ◽  
Joseph T. Snow ◽  
Qiong Zhang ◽  
Rosalind E. M. Rickaby

AbstractAmmonia oxidation by archaea and bacteria (AOA and AOB), is the first step of nitrification in the oceans. As AOA have an ammonium affinity 200-fold higher than AOB isolates, the chemical niche allowing AOB to persist in the oligotrophic ocean remains unclear. Here we show that marine isolates, Nitrosopumilus maritimus strain SCM1 (AOA) and Nitrosococcus oceani strain C-107 (AOB) have contrasting physiologies in response to the trace metals iron (Fe) and copper (Cu), holding potential implications for their niche separation in the oceans. A greater affinity for unchelated Fe may allow AOB to inhabit shallower, euphotic waters where ammonium supply is high, but competition for Fe is rife. In contrast to AOB, AOA isolates have a greater affinity and toxicity threshold for unchelated Cu providing additional explanation to the greater success of AOA in the marine environment where Cu availability can be highly variable. Using comparative genomics, we predict that the proteomic and metal transport basis giving rise to contrasting physiologies in isolates is widespread across phylogenetically diverse marine AOA and AOB that are not yet available in pure culture. Our results develop the testable hypothesis that ammonia oxidation may be limited by Cu in large tracts of the open ocean and suggest a relatively earlier emergence of AOB than AOA when considered in the context of evolving trace metal availabilities over geologic time.


ChemInform ◽  
1987 ◽  
Vol 18 (32) ◽  
Author(s):  
U. P. SINGH ◽  
R. GHOSE ◽  
A. K. GHOSE

1991 ◽  
Vol 18 (6) ◽  
pp. 893-903 ◽  
Author(s):  
Inderjit Singh ◽  
Donald S. Mavinic

Samples were taken from 72 high-rise apartment suites (6 suites in 12 individual high-rise towers) and 60 single-family houses located within the Greater Vancouver Regional District. The influence of the following factors on trace metal concentrations in 1-L first-flush drinking water samples and “running” hot water samples was investigated: building height, location, plumbing age, type of plumbing, and type of building. Results of this survey show that with the exception of building height, all factors had a correlation with one or more of the trace metals investigated. The trace metals examined were lead, copper, iron, and zinc. Lead was influenced primarily by building type, copper by plumbing age and type of plumbing, and iron by location. Elevated lead levels were associated with high-rise samples. New copper plumbing systems resulted in high copper levels. Highest iron levels in the drinking water were measured in the East Vancouver location. Zinc did not show a distinct correlation with any of the factors investigated. Brass faucets were the primary source of zinc in tap water. They also contributed substantially to the lead detected in the 1-L first-flush sample. Metal concentrations measured in the high-rise and house samples were compared with the U.S. Environmental Protection Agency's (USEPA) maximum contaminant levels (MCLs) and the proposed “no-action” level for lead. In high-rise samples, the 0.01 mg/L “no-action” level proposed for lead was exceeded in 43% of the samples, and 62% of the samples exceeded the current 1.0 mg/L MCL standard for copper. In single-family house samples, these values were 47% and 73%, respectively. The average lead concentrations were 0.020 mg/L for all high-rise samples and 0.013 mg/L for house samples. Regulatory levels stated above would still be exceeded in 6% of the cases for lead and 9% of the cases for copper, even after prolonged flushing of the tap in a high-rise building. In all cases associated with single-family houses, flushing the cold water tap for 5 minutes was successful in achieving compliance levels. Key words: aggressive water, compliance, corrosive, drinking water, first-flush, GVRD, high-rise, single-family house, trace metals, USEPA.


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