| The Holocene period is nearly correlated with human, in which Human being evolved from primitive people to modern people and many cultures formed. In consequence, the climate change in this period has become a hot spot in past global change research. Some researchs from east Asion monsoon exist controversies and uncertainties, and many further researches are of necessity. Wanxiang Cave is on the Eastern Qinghai Tibetan Plateau, which lie in cross bedding of southeast and southwest summer monsoon, is a ideal station for paleoclimate change research. In this article, we analysed theδ13C andδ18O records of a well dated stalagmite (WXB07-4) which was found in Wanxiang cave, and reconstructed the climate change and vegetation evolvement history from 9ka BP to 5.3ka BP. The main conclusions we got are here below:(1) By and large, the variation trends of the WXB07-4 stalagmiteδ13C andδ18O records are corresponding, it is indicated that the vegetation evolvement respond to the climate change rapidly; however, there also exists time lag between the vegetation evolvement and climate change in some period of time, and we cannot simply think the time lag is longer in the periods of cold and dry.(2) After the comparison among Qunf cave, Dongge cave, and Wanxiang cave records, we found the southwest monsoon pass through the course of " weak→strong→stable→weak ", which demonstrated monsoon variations has four stages:①9-8.3 ka BP monsoon weakened period,δ18O value got heaviest about 8.3ka BP,and the vegetation is sensitive to climate change in this period; in the meantime, C3/C4 vegetation ratio, the density and extent of vegetation gradully decrease.②8.3-7.8 ka BP monsoon gradully strengthened period, after coldest dot of 8200 year event, C3/C4 vegetation ratio, the density and extent of vegetation gradully increase.③7.8-6.1 ka BP monsoon stable and strong period, the variation trends of the WXB07-4 stalagmiteδ18O andδ13C records are corresponding in principle, especially, peaks and bottoms of the curves are one to one correspondence, which indicate the vegetation evolvement is also responded to climate change in general, the dramatic variation of theδ13C record is responded to kinetic isotope fractionation.④6.1-5.3ka BP monsoon weakened period, C3/C4 vegetation ratio, the density and extent of vegetation gradully decrease.(3) Many cold/dry events from Qunf cave, Dongge cave, and Wanxiang cave records:①The coldest dot of 8200 year event (MW4) is dated at 8.35±0.06 ka in WXB07-4 stalagmiteδ18O record, it is in conformity with theδ18O record of Dongge cave, Qunf cave, GISP2 ice core, Ireland stalagmite, and Heshang cave within uncertainty of dating.②a cold/dry event(MW3) around 7.25ka BP lasted about 170 years, and WXB07-4 stalagmiteδ13C record show the vegetation evolvement lag behind climate change about 100 years.③a cold/dry event(MW2) around 6.25ka BP, the records of WXB07-4 stalagmiteδ13C,DA stalagmiteδ18O, and Q5 stalagmiteδ18O show the weak monsoon in this period, but this cold/dry event is unconspicuous in WXB07-4 stalagmiteδ18O record. We think one possible reason is that vegetation change in company with inorganic factors influence stalagmiteδ13C value, so that, clearer informations of climate change inδ13C compared withδ18O record of stalagmite in some special periods.④a cold/dry event(MW1) around 5.6ka BP, it is synchronicity with the Bond4 in DA stalagmiteδ18O and a weak monsoon priod in Q5 stalagmiteδ18O record, also correlate with a cold/dry event about 5.5-5.3ka BP in Atlantic sediment record.(4) Theδ18O record of WXB07-4 stalagmite can well correlated with the reeord of Sun spot number; on the one hand, gradually weakened monsoon is responded to weakened solar activity between 9 and 5.3ka BP; on the other hand, the peaks and bottoms of two curves records are one to one correspondence. There also exist inconformities in two records (e.g 8-7.2kaBP and 6.2-5.6ka), it seems to suggest that the southwest mnsoon is also driven by other mechanisms besides sun in century scale.(5) Theδ18O record of WXB07-4 stalagmite can well correlated with the record of Ti concent in Cariaco basin, shows that the intensity of southwest monsoon is connected with the mean position of ITCZ, and the movments of ITCZ could magnify the changes of monsoon in middle-low latitude. (6)Theδ18O record of WXB07-4 stalagmite is well anti-correlated with GISP2 ice coreδ18O record, shows that the temperature change in polar region is related with southwest monsoon change. Some cold/dry event in WXB07-4 stalagmiteδ18O record is also reflected in GISP2 ice coreδ18O record, included 5.6,6.25,7.25 and 8.2kaBP cold/dry event, and they are coincidental within uncertainty of dating, maybe have a globally reflect. It is also illuminate that climate change has a close connection bitween middle-low latitude and high latitude ragions.
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