LIGNIN-DERIVED PHENOLIC-COMPOUNDS IN DIFFERENT TYPES OF FEAT PROFILES IN HOKKAIDO, JAPAN

How is the composition of organic matter of peat related to the environment of the peatland? How does it change with the process of peat formation? How does it change when the peatland is affected by the lowering of the ground water table? What are the relationships between the organic matter composition of peat and peatland plants? These are problems which we attempted to address in this study. Feat samples were collected layer-wise from four different peat profiles formed under different environments in Hokkaido, Japan. The basic properties of the peat profiles, i.e. major peat-forming plants, contents of carbon and nitrogen, C/N ratio, pH, degree of humification analyzed by several methods, were described and compared. As one of the keys to answer the above-mentioned questions, we selected lignin-derived phenolic compounds that are released by CuO-NaOH oxidation. The composition of the phenolic compounds varied remarkably among the peat layers differing in peat-forming plants and in the mode of accumulation, The classification into high-moor, transitional moor, and low-moor peat was not sufficient to explain the composition of the phenolic compounds of peat. Differences in major peat-forming plants, i.e. sphagnum moss or sedges in high-moor peat, and Phragmites or Alnus in low-moor peat exerted significant effects on the phenolic composition.