Abstract

Stable carbon and nitrogen isotope ratios ( δ 13C, δ 15N) are frequently used to decipher organic matter sources and transformation processes. Here, we present stable isotope data of suspended matter and sediments from the Ob and Yenisei estuaries and the Kara Sea (Arctic Ocean) in order to figure out how they are influenced by seasonal and interannual changes in river run-off, ice coverage, and biological activity. Our study shows a progressive increase of stable carbon and nitrogen isotopic ratios in offshore direction and a positive correlation of salinity with δ 13C. Differences among the correlation of individual annual suspended-matter data sets reveal a multitude of processes modulating δ 13C ratios such as sporadic plankton blooms, variations in riverine end-members and annual river run-off. Despite this variability the correlation of salinity with δ 13C of suspended matter from the surface water is very similar to that of surface sediments with the average salinity of the ice-free period. However, sediments show a shift to higher δ 13C values by about 2.2‰. Since sinking particles in deep water are similar to sedimentary δ 13C ratios, the correlation of salinity with δ 13C of sediments has been taken to reconstruct the paleosalinity of a sediment core off the Yenisei river mouth since 10,000 yr BP.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.