The Component Of Hani Peat GDGTs And Its Response To Holocene Climate Changes

Drought and typhoon were frequently in recent years and several climate conferences were held around the word, which have made people realizing deeply the importance of studying climate change, especially the climate in Holocene. Modern climate is continuation and development of the Holocene climate, therefore the reconstruction of Holocene climate is of special significance. Peat has some good advantages in all carriers of studying palaeoclimate change, such as high resolution; less interference; wide distribution and including more information, which can make us acquire continuous and high resolution climate change information. The Glycerol Dialkyl Glycerol Tetraethers (GDGTs) which exists widely in peat is a hot index recently. It is the major component of Microbial lipid and its structure and composition are sensitive to environment, because of which it can keep the information of palaeoclimate change. Currently, GDGTs have been applied in sea, lake, and soil and reached many great results. However the study of GDGTs in peat is rare. In this thesis, an 885cm peat column collected in Hani peatland in Northeast China was tested by HPLC-MS. The composition and distribution characteristics were described. Besides, some indexes about GDGTs that have been found by other researchers were applied to Hani peat for trying reconstruct the palaeoclimate change in the area, the result showed that palaeoclimate change since 16ka in Hani can be divided 6 period. ? 16170 cal aBP?11550cal aBP, Deglacial,temperature keep rising but also be cold.?11550 cal aBP?10190cal aBP, beginning of Holocene, temperature rise sharply and then rapidly reduce, climate is warm as a whole. ? 10190cal aBP-8316cal aBP, early Holocene, temperature rise with wave. ? 8316 cal aBP?6130cal aBP,warm period in Holocene and temperature is fairly stable. ? 6130 cal aBP?1010 cal aBP, temperature fall. ?1010 cal aBP?0 aBP, temperature rise,but in a low position in whole Holocene. The sequence of palaeoclimate change have a good reflection for global climatic events, including OD-B(?)iling-MD-Aller(?)d-IACP-Aller(?)d-YD-IRD7-IRD6-IRD4-IRD3-IRD2-IRD1.Besides,the sequence is in good agreement with that reconstructed by other indexes, such as phytolith, humification degree, oxygen isotope and sporopollen, showing that GDGTs indexes has a good adaptability in Hani peat and the sequence by GDGTs is reliable.