19To understand the responses of terrestrial vegetation in central Japan to global 20 climate changes, we generated a record of lignin composition from core BIW08-B in 21 Lake Biwa, central Japan, during the last 147,000 years by TMAH-pyrolysis-GC/MS. 22Lignin abundance was intermittently elevated and associated with a high ratio of 23 cinnamyl (C) to vanillyl (V) phenols (C/V ratio) of lignin, suggesting episodic inflows 24 1 of herbaceous plant-derived organic matter into Lake Biwa. The largest inflow occurred 25 during the last deglaciation. Variation in the ratio of syringyl (S) to vanillyl (V) phenols 26 (S/V ratio), which is a contribution index of angiosperms against gymnosperms, showed 27 a precession-like cycle, was consistent with a pollen record from Lake Biwa, and 28 showed a pattern similar to the S/V record from an offshore marine site in the 29 northwestern Pacific. The variation reflected the regional replacement of cool-temperate 30 deciduous broadleaf forests, subalpine conifer forests, and Japanese cedar forests in 31 central Japan caused by the repetition of warmer, dry and cooler, wet climates on a 32 precession cycle. 33 34

We generated a record of lignin and fatty acid compositions from the TK-2004 core in Takano Basin, central Japan, during 39-162 ka by TMAH-thermochemolysis-GC/MS. We tested lignin and fatty acid compositions in the sediments of a small lake (1.88 km 2 watershed) as a paleovegetation proxy to understand the responses of terrestrial vegetation in central Japan to global climate change. Variation in terrestrial organic carbon contents estimated by C/N and ∑8 was parallel to the total organic content (TOC) variation, suggesting that the inflow of terrestrial organic matter was a major factor determining the TOC. The ratio of mid-chain C 20 -C 24 n-fatty acids to short-chain C 14 -C 18 n-fatty acids (MFA/SFA ratio) and the ratio of cinnamyl to vanillyl phenols (C/V ratio) of lignin gradually increased from mid-MIS 6 to early MIS 3. The increase in both parameters suggested increase in the contribution of submerged and floating plants as the flats were expanded in the lake margin. The ratio of syringyl to vanillyl phenols (S/V ratio) corresponded to the pollen vegetation index. This correspondence indicated that the S/V ratio reflected the relative abundance of angiosperms to gymnosperms in the Takano Basin. The consistency of the S/V ratio at the site of core TKN-2004 and the other two locations suggests that the S/V ratio in a small basin is a robust proxy for terrestrial vegetation on a regional scale.