Paleohydrologic reconstruction based on n-alkane distributions in ombrotrophic peat
نویسندگان
چکیده
Proxies such as plant macrofossils, humification indices and testate amoebae have been developed to reconstruct past hydrological variability in ombrotrophic peatlands. Reconstructions based on these approaches have resulted in records of decadalto centennial-scale moisture variability in regions of North America and elsewhere. Although the various peatland moisture proxies generally show significant temporal covariance, multi-proxy approaches can refine knowledge of the multivariate nature of climate change and increase confidence in interpretations. Here, we demonstrate that ratios of the abundances of n-alkanes provide a new and efficient way of reconstructing past peatland surface moisture change. We found strong correlations among n-alkane indices, humification indices and testate amoebae-inferred water table depths from a single core. Biogeochemical proxies can be used in paleohydrological reconstructions for ombrotrophic bogs to provide a new and complementary source of data from these under-utilized paleoclimate archives. 2006 Elsevier Ltd. All rights reserved.
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