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Jeziorski Adam Nelligan Clare Corrigan Dara Meyer-Jacob Carsten Paterson Andrew M. Smol John P. 《Journal of Paleolimnology》2021,66(4):371-387
Journal of Paleolimnology - Peninsula Lake, Ontario, Canada, is a Precambrian Shield lake that has experienced many environmental stressors since European settlement of the watershed in the... 相似文献
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Carsten Meyer-Jacob Hendrik Vogel Florian Boxberg Peter Rosén Michael E. Weber Richard Bindler 《Journal of Paleolimnology》2014,52(3):245-255
We present an independent calibration model for the determination of biogenic silica (BSi) in sediments, developed from analysis of synthetic sediment mixtures and application of Fourier transform infrared spectroscopy (FTIRS) and partial least squares regression (PLSR) modeling. In contrast to current FTIRS applications for quantifying BSi, this new calibration is independent from conventional wet-chemical techniques and their associated measurement uncertainties. This approach also removes the need for developing internal calibrations between the two methods for individual sediments records. For the independent calibration, we produced six series of different synthetic sediment mixtures using two purified diatom extracts, with one extract mixed with quartz sand, calcite, 60/40 quartz/calcite and two different natural sediments, and a second extract mixed with one of the natural sediments. A total of 306 samples—51 samples per series—yielded BSi contents ranging from 0 to 100 %. The resulting PLSR calibration model between the FTIR spectral information and the defined BSi concentration of the synthetic sediment mixtures exhibits a strong cross-validated correlation ( \( {\text{R}}^{ 2}_{\text{cv}} \) = 0.97) and a low root-mean square error of cross-validation (RMSECV = 4.7 %). Application of the independent calibration to natural lacustrine and marine sediments yields robust BSi reconstructions. At present, the synthetic mixtures do not include the variation in organic matter that occurs in natural samples, which may explain the somewhat lower prediction accuracy of the calibration model for organic-rich samples. 相似文献
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