Stable oxygen isotope ratio of the deep sea and ice core record has been offered paleoenvironmental information (e. g. Shackleton and Opdyke, 1973; Dansgaard et al., 1964, 1993; Bond et al., 1992). It has been revealed glacial-interglacial cycles and other global environment changes in the Quaternary period. In the terrestrial area of the mid-latitude the palynological studies of peat and/or lake sediment have been played important roles for regional and local paleo-botanical and environment reconstructions. Pollen is, however, not well preserved in the aerobic condition, restricting the use of soil and loess deposits for pollen analysis.
Phytoliths, also referred to as plant opal or plant silica bodies, are microscopic bodies formed from silica that occurs in ground water as monosilicic acid. The growing plant absorbs silica into its tissues, forming bodies composed of opaline silica (SiO₂:nH₂O) (Piperno and Pearsall, 1993). Phytoliths is much more preserved in the aerobic condition than pollen, there is a possibility that we can find remnants of phytolilths in sequential paleosoil or leoss deposits. If we can use phytoliths as the proxy of past environment, it is quite useful because we could directly estimate paleoenvironment from regional or local terrestrial deposits. Therefore we study the relationship between stable oxygen isotope ratio of phytoliths and environmental factors. In this study we present the preliminary results about phytoliths from living leaves of Japanese Sasa and Phyllostachys toward the paleoenvironmental reconstruction. In this study we will discuss the relationship between the stable oxygen isotope ratio of phytoliths and several environmental factors such as temperature, precipitation, distance from sea, altitude, etc.