Peat molecular fossils recording paleoclimatic change and organism replacement

The occurrence of the dominant C-23 n-alkane derived from bryophyte was dem onstrated to be related to the cold climate, based on the GC and GC/MS anal yses on a 40-cm long peat core, in which this compound exponentially varies in abundance with the depth corresponding to the well-known second Little Ice Age. Both the variation of the chemical components of modern bryophyte resulted from climatic change and the ecological data about the biological growth influenced by climate shed light on the point that the variation of this compound in the peat was related to the cold climate. This was also ev idenced by the previously-reported lacustrine data. In addition, the variat ions of the ratios of ketones/esters and C-24 n-alkene/n-alkane (C-24:1/C-2 4:0) display the trend identical with that of organisms, implicating the re placement between bryophyte and monocotyledon occurring in the peat core.