摘要
研究中国降雨格局变化对理解东亚夏季风演化意义重大。本文分析了珠江三角洲柱状样ZJK03-Z中浅水底栖有孔虫常见种Rotalidium annectens的平均初房大小、微球型/显球型比值和壳体δ18O值,以及底栖有孔虫组合中瓷质壳的百分含量,探讨它们对由夏季风降雨引起的河口水体盐度变化的响应,得到了珠江三角洲3114—1260a BP季风降雨的强度变化,识别出了这期间14次季风降雨减少的偏干期。与南美洲Cariaco海盆的钛含量记录对比,二者一致的结果表明,珠江三角洲晚全新世的东亚夏季风降雨与热带辐合带(ITCZ)的南北移动密切相关:夏季风降雨减少,对应于ITCZ纬度位置的南移。
Mean proloculus size(MPS), proportion of microspheric and meglospheric forms, and δ18O of calcareous shells of a common species Rotalidium annectens, as well as the abundance of porcelaneous tests in total benthic foraminiferal fauna from Core ZJK 03-Z in Zhujiang(Pearl) River Delta, northern South China Sea in Guangdong Province, South China were measured to indicate the fluctuation of salinity in the estuary due to summer monsoon rainfall input. Fourteen short-term dry periods(reduced summer monsoon rainfall) were recognized in this region during 3114—1260 a BP. The monsoon variation is consistent with the Intertropical Convergence Zone(ITCZ) movement reflected by Ti% record from the Cariaco Basin in South America. The strength of East Asian summer monsoon rainfall in Zhujiang River Delta during the Late Holocene is closely related to the southward and northward movement of the ITCZ: the reduced monsoon rainfall periods was coupled with the southward movement of ITCZ, or vice versa.
出处
《海洋与湖沼》
CAS
CSCD
北大核心
2014年第2期225-232,共8页
Oceanologia Et Limnologia Sinica
基金
国家自然科学基金项目
40906038号
41006036号
41206044号
海洋公益性行业科研专项项目
200805063号
海洋地质国家重点实验室开放基金
MG0903号
