|
Titel |
Biogeochemical variability during the past 3.6 million years recorded by FTIR spectroscopy in the sediment record of Lake El'gygytgyn, Far East Russian Arctic |
VerfasserIn |
C. Meyer-Jacob, H. Vogel, A. C. Gebhardt, V. Wennrich, M. Melles, P. Rosén |
Medientyp |
Artikel
|
Sprache |
Englisch
|
ISSN |
1814-9324
|
Digitales Dokument |
URL |
Erschienen |
In: Climate of the Past ; 10, no. 1 ; Nr. 10, no. 1 (2014-01-31), S.209-220 |
Datensatznummer |
250116906
|
Publikation (Nr.) |
copernicus.org/cp-10-209-2014.pdf |
|
|
|
Zusammenfassung |
A number of studies have shown that Fourier transform infrared spectroscopy
(FTIRS) can be applied to quantitatively assess lacustrine sediment
constituents. In this study, we developed calibration models based on FTIRS
for the quantitative determination of biogenic silica (BSi; n = 420;
gradient: 0.9–56.5%), total organic carbon (TOC; n = 309; gradient:
0–2.9%), and total inorganic carbon (TIC; n= 152; gradient: 0–0.4%)
in a 318 m-long sediment record with a basal age of 3.6 million years from Lake
El'gygytgyn, Far East Russian Arctic. The developed partial
least squares (PLS) regression models yield high cross-validated (CV)
R2CV = 0.86–0.91 and low root mean square error of
cross-validation (RMSECV) (3.1–7.0% of the gradient for the different
properties). By applying these models to 6771 samples from the entire
sediment record, we obtained detailed insight into bioproductivity
variations in Lake El'gygytgyn throughout the middle to late
Pliocene and Quaternary. High accumulation rates of BSi indicate a
productivity maximum during the middle Pliocene (3.6–3.3 Ma), followed by
gradually decreasing rates during the late Pliocene and Quaternary. The
average BSi accumulation during the middle Pliocene was ~3 times
higher than maximum accumulation rates during the past 1.5 million years. The indicated
progressive deterioration of environmental and climatic conditions in the
Siberian Arctic starting at ca. 3.3 Ma is consistent with the first
occurrence of glacial periods and the finally complete establishment of
glacial–interglacial cycles during the Quaternary. |
|
|
Teil von |
|
|
|
|
|
|