CUO-OXIDATION PRODUCTS OF PEAT AS A KEY TO THE ANALYSIS OF THE PALEO-ENVIRONMENTAL CHANGES IN A WETLAND

The peat profile in the Ohnohara wetland in Central Japan is very valu able due to the continuous accumulation of peat since even before the last glacial maximum era. Using this profile, we investigated the envi ronmental and climatic changes which occurred since the last glacial e ra based on the determination of the contents and composition of pheno lic compounds released from peat by CuO oxidation. For describing the changes in the anaerobic/aerobic conditions in the wetland, the phenol ic degradation products were grouped into phenolic acids, acetophenone s, cinnamic acids, and phenolic aldehydes. The changes in the ratios b etween cinnamyl, vanillyl, syringyl, and p-hydroxyphenyl compounds as well as the ratio of ferulic acid/p-coumaric acid corresponded well to the changes in the vegetation type of the wetland. Phenolic compounds released from the peal samples corresponded A-ell to the observations based on palynological studies and to the data relating to post-glaci al climatic changes. Therefore, it is suggested that the contents and composition of phenolic compounds of peat could be used as an index of the changes in paleo-environments.