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对中国东部中纬度季风区内的两处山地泥炭—神农架大九湖泥炭和天目山千亩田泥炭腐殖化度进行了研究,并对两剖面的孢粉记录、有机质含量、TOC和Rb/Sr对比分析,结果表明在东亚季风区山间盆地,气候越干冷时泥炭的分解就越强烈,以吸光度表征的腐殖化度就越高;相反,当气候较温暖潮湿时泥炭主要处于还原状态,分解较慢,腐殖化度较低.大九湖剖面的腐殖化度记录了晚冰期(约16.0～11.4 cal ka BP)中的新仙女木(YD)(约11.4～12.6 cal ka BP)冷干事件、博令-阿勒罗德暖湿期(B-A暖期,约12.6～15.2 cal ka BP)、最老仙女木冷干事件(OD,约15.2～16.0 cal ka BP)、早全新世的湿润期(约11.4～9.4 cal ka BP)、8.2 cal ka BP前后的冷干事件和约7.0～4.2 cal ka BP之间的全新世最佳适宜期.神农架大九湖和天目山千亩田近5000a以来的泥炭腐殖化度记录有着很好的一致性,表明相近纬度不同经度的山地泥炭对东亚季风降水变化的响应是同步的.近5000a来的气候变化在两个山地泥剖面中几乎同步记录有3大阶段:4.9～3.5 cal ka BP,季风降水整体处于高值,但波动剧烈,其中,在约4.2 cal ka BP前后,季风降水急剧下降,在3.7 cal ka BP前后达到最干旱的峰值后又快速回升;3.5～0.9 cal ka BP,季风降水强度整体较弱,但也存在明显的次级干湿波动;0.9 cal ka BP以来,吸光度值逐渐降低,表明季风降水增多.与中国东部季风区其他高分辨率沉积记录对比,文中亚高山泥炭记录的约1.6万年以来的气候变化响应了北半球夏季太阳辐射的统一驱动.
Two peat monsoons in the middle-latitude monsoon region of eastern China, peat charcoal in Shennongjia Dachaoshan and Qianmu Mountain in Tianmu Mountain, were studied. Pollen record, organic matter content, TOC and Rb / Sr The results show that in the monsoon region of the East Asian monsoon, the peat decomposes more strongly when the climate is drier and the humification degree characterized by absorbance is higher. On the contrary, when the climate is warm and humid, the peat is mainly in the state of reduction, Decomposition is slow and the degree of humification is low.The degree of humification in the Daxiuhu section recorded the temperature of about 11.4 ~ 12.6 cal ka BP in the late glacial period (about 16.0 ~ 11.4 cal ka BP) Cold-dry event, Bourlay-Alerode warm-wet period (BA warm period, about 12.6 ~ 15.2 cal ka BP), Oldest wood of the fairy wood cold-dry event (OD of about 15.2-16.0 cal ka BP), Early Holocene (About 11.4 ~ 9.4 cal ka BP), cold-dry events before and after 8.2 cal ka BP, and the best suitable period of Holocene between about 7.0 and 4.2 cal ka BP. Since Shennongjia Great Jiuhu and Tianmu Mountain Of the peat humification degree record has a very good consistency, indicating that similar latitudes and longitudes of different lengths of mud The response to the monsoonal precipitation in East Asia is synchronous.The climatic changes in recent 5000 years have recorded three phases almost simultaneously in the two mudstone profiles: 4.9 ~ 3.5 cal ka BP, the monsoon precipitation is high at the whole, but fluctuated violently, Before and after about 4.2 cal ka BP, the monsoon rainfall dropped sharply and rose rapidly after reaching the most arid peak before and after 3.7 cal ka BP. However, the monsoon precipitation intensity was generally weak at 3.5 ~ 0.9 cal ka BP, but there was also significant Sub-level wet-dry fluctuations; since 0.9 cal ka BP, the absorbance value gradually decreased, indicating an increase in monsoon precipitation. Compared with other high-resolution sedimentary records in the monsoon region of eastern China, the climate change recorded in the Paleo-Alpine peat about 16,000 years Responds to the unified driving of summer solar radiation in the northern hemisphere.