Isotopic and pollen evidence of paleo-vegetation changes in loess plateau of Luochuan, China

Carbon isotopes in loess through S 0 to S 11 at Luochuan section in Shanxi province, China were studied. The curve of δ 13 C compares well to that of the oxygen isotope in deep sea sediments from Deep Sea Drilling Project Site 607 drill hole. There is a negative peak of δ 13 C within S 5 paleosol where the content of δ 13 C is −16.615‰, shows that the climatic of that period is optimum, and the vegetation is likely forest. Compared with the pollen analysis, we conclude that the vegetation type of palesol S 0 ,S 1 ,S 4 ,S 8 ,S 9 , whose δ 13 C content is −5.85–−10.00‰, is forest-grass. The d13C content of paleosol S 2 , S 3 , S 6 , S 7 is −8.72∼−6.95‰, and their vegetation is grass. The loess layer L 1 , L 2 , L 5 , L 6 , L 8 , L 9 represent the severe cold-dry glacial period with the δ 13 C content of −3.7– −2.27‰, and their vegetation belongs to steppe-desert. The research of paleo-vegetation type is significant to anti-soil erosion in the loess plateau of China.