Effect of pedogenesis on the stable isotopic composition of calcretes andn‐alkanes: Implications for palaeoenvironmental reconstruction

Sedimentology ◽  
2018 ◽  
Vol 66 (5) ◽  
pp. 1560-1579 ◽  
Author(s):  
Vijayananda Sarangi ◽  
Anurag Kumar ◽  
Prasanta Sanyal
Keyword(s):  
Isotopic Composition ◽  
Palaeoenvironmental Reconstruction ◽  
Stable Isotopic Composition ◽  
Stable Isotopic

Seasonal trends in the stable isotopic composition of snow and meltwater runoff in a subarctic catchment at Okstindan, Norway

2004 ◽  
Vol 35 (2) ◽  
pp. 119-137 ◽  
Author(s):  
S.D. Gurney ◽  
D.S.L. Lawrence
Keyword(s):  
Isotopic Composition ◽  
Mean Value ◽  
Mean Values ◽  
Stable Isotopic Composition ◽  
Meltwater Runoff ◽  
Stable Isotopic ◽  
The Mean ◽  
The Difference ◽  
Δ18o And Δd

Seasonal variations in the stable isotopic composition of snow and meltwater were investigated in a sub-arctic, mountainous, but non-glacial, catchment at Okstindan in northern Norway based on analyses of δ18O and δD. Samples were collected during four field periods (August 1998; April 1999; June 1999 and August 1999) at three sites lying on an altitudinal transect (740–970 m a.s.l.). Snowpack data display an increase in the mean values of δ18O (increasing from a mean value of −13.51 to −11.49‰ between April and August), as well as a decrease in variability through the melt period. Comparison with a regional meteoric water line indicates that the slope of the δ18O–δD line for the snowpacks decreases over the same period, dropping from 7.49 to approximately 6.2.This change points to the role of evaporation in snowpack ablation and is confirmed by the vertical profile of deuterium excess. Snowpack seepage data, although limited, also suggest reduced values of δD, as might be associated with local evaporation during meltwater generation. In general, meltwaters were depleted in δ18O relative to the source snowpack at the peak of the melt (June), but later in the year (August) the difference between the two was not statistically significant. The diurnal pattern of isotopic composition indicates that the most depleted meltwaters coincide with the peak in temperature and, hence, meltwater production.

Prediction method for determining the carbon stable isotopic composition of berry sugars in the original must of Chardonnay wines

2021 ◽  
pp. 130854
Author(s):  
Fumikazu Akamatsu ◽  
Hideaki Shimizu ◽  
Yukari Igi ◽  
Aya Kamada ◽  
Kazuya Koyama ◽  
...  
Keyword(s):  
Isotopic Composition ◽  
Prediction Method ◽  
Stable Isotopic Composition ◽  
Stable Isotopic

scholarly journals Stable isotopic composition of top consumers in Arctic cryoconite holes: revealing divergent roles in a supraglacial trophic network

2021 ◽  
Vol 18 (5) ◽  
pp. 1543-1557
Author(s):  
Tereza Novotná Jaroměřská ◽  
Jakub Trubač ◽  
Krzysztof Zawierucha ◽  
Lenka Vondrovicová ◽  
Miloslav Devetter ◽  
...  
Keyword(s):  
Isotopic Composition ◽  
Isotopic Ratio ◽  
Isotopic Fractionation ◽  
Mechanistic Explanation ◽  
High Arctic ◽  
Biologically Active ◽  
Glacier Surface ◽  
Stable Isotopic Composition ◽  
Stable Isotopic ◽  
Trophic Network

Abstract. Arctic cryoconite holes represent highly biologically active aquatic habitats on the glacier surface characterized by the dynamic nature of their formation and functioning. The most common cryoconite apex consumers are the cosmopolitan invertebrates – tardigrades and rotifers. Several studies have highlighted the potential relevance of tardigrades and rotifers to cryoconite holes' ecosystem functioning. However, due to the dominant occurrence of prokaryotes, these consumers are usually out of the major scope of most studies aimed at understanding biological processes on glaciers. The aim of this descriptive study is to present pioneering data on isotopic composition of tardigrades, rotifers and cryoconite from three High Arctic glaciers in Svalbard and discuss their role in a cryoconite hole trophic network. We found that tardigrades have lower δ15N values than rotifers, which indicates different food requirements or different isotopic fractionation of both consumers. The δ13C values revealed differences between consumers and organic matter in cryoconite among glaciers. However, the mechanistic explanation of these variations requires further investigation focused on the particular diet of cryoconite consumers and their isotopic ratio. Our study introduces the first observation of carbon and nitrogen stable isotopic composition of top consumers in cryoconite holes analysed by an improved method for cryoconite sample processing, paving the way for further studies of the supraglacial trophic network.

scholarly journals Stable isotopic composition of atmospheric precipitation on the Crimean Peninsula and its controlling factors

2018 ◽  
Vol 565 ◽  
pp. 61-73 ◽  
Author(s):  
Yuri V. Dublyansky ◽  
Alexander B. Klimchouk ◽  
Sergey V. Tokarev ◽  
Gennady N. Amelichev ◽  
Lukas Langhamer ◽  
...  
Keyword(s):  
Isotopic Composition ◽  
Atmospheric Precipitation ◽  
Controlling Factors ◽  
Crimean Peninsula ◽  
Stable Isotopic Composition ◽  
Stable Isotopic ◽  
The Crimean Peninsula

Geographic effects on stable isotopic composition of precipitation across Thailand

2020 ◽  
Vol 56 (2) ◽  
pp. 111-121
Author(s):  
Jeerapong Laonamsai ◽  
Kimpei Ichiyanagi ◽  
Kiattipong Kamdee
Keyword(s):  
Isotopic Composition ◽  
Stable Isotopic Composition ◽  
Stable Isotopic ◽  
Geographic Effects
Sign in / Sign up

Export Citation Format

Share Document