最近500年来福建玉华洞石笋氧同位素记录及气候意义  

Stalagmite δ^(18)O Record from Yuhua Cave over the Past 500 Years and Its Regional Climate Significance

作　　者：姜修洋[1] 李志忠[1] 李金全[1] 孔兴功[2] 郭允[2] 

机构地区：[1]福建师范大学地理科学学院,湿润亚热带生态地理过程省部共建教育部重点实验室,福建福州350007 [2]南京师范大学地理科学学院,江苏南京210046

出　　处：《地理科学》2012年第2期207-212,共6页Scientia Geographica Sinica

基　　金：国家自然科学基金(41002061);福建省自然科学基金(2010J05093);福建省公益类基金(2010R1037-3)资助

摘　　要：基于福建将乐玉华洞一支石笋(YH1)4个230Th年龄和370个氧同位素数据,并利用具有年层时标的湖北清江和尚洞石笋氧同位素记录的校正,重建了AD 1530以来1~3 a分辨率的石笋氧同位素序列。与当地现代器测气象资料对比发现,最近60 a来玉华洞石笋δ18O与当地夏半年降水量相关性最为显著(R=-0.35,n=55),而受温度的影响较弱,玉华洞石笋氧同位素较好的指示了当地夏半年降水量变化的信息。最近100 a来,福建玉华洞石笋的氧同位素组成具有逐渐变重的趋势,与其他地区高分辨率石笋δ18O具有相同的变化趋势,而且也与季风指数指示的季风减弱趋势相一致,进一步证实季风区石笋δ18O反映了东亚季风大尺度环流特征;在小冰期中后期(AD 1530~1850),玉华洞石笋δ18O在平均值-5.9‰高频振荡,存在一系列的数十年际尺度的季风增强和减弱事件,与亚洲—太平洋涛动(Asian Pacific Oscillation,APO)指数密切相关,说明玉华洞石笋δ18O所指示的降水信息受APO变化的影响。Based on 4 230Th dates and 370 stable oxygen isotope ratios（δ18O） obtained from a stalagmite collected from Yuhua Cave,Jiangle,Fujian,and combined with the age calibration of the top 100 years using the annually band counting stalagmite from Heshang Cave,an high-resolution oxygen isotope profile of the past 500 years was established.Comparison of the stalagmite δ18O record with instrumental precipitation data at Yong’an in the past 60 years indicates a high parallelism between the δ18O record and the total summer months（April to September） precipitation,suggesting that the stalagmite δ18O is a good proxy for the local summer monsoon precipitation.A comparison with other high-resolution stalagmites records shows that the trend of increase value of the δ18O during the past 100 years was similar in the East Asian Monsoon area.This supports the idea that the δ18O of the stalagmite from monsoon area indicates characteristics of the East Asian monsoon circulation.Comparison between the δ18O of stalagmite with Asian-Pacific Oscillation index shows a big similarity.On centennial to dacadal time scales,when IAPO is of the high value,the δ18O values will get much lower,and vice versa.Our result demonstrates a strong linkage between Asian monsoon precipitation and the Pacific Ocean via ocean/atmosphere interaction.

关 键 词：玉华洞 石笋 氧同位素 亚洲-太平洋涛动(APO)指数 季风环流 

分 类 号：P532[天文地球—古生物学与地层学]