| 本文已被：浏览 2241次 下载 1285次 |
码上扫一扫！ |
|
|
| 近2000年来福建南部海岸沙丘记录的风沙活动序列 |
|
徐晓琳1,2, 李志忠1,2,3, 靳建辉1,2,3, 程 延1,2, 于晓莉1,2, 赖海成1,2, 申健玲1,2, 苑秀全1,2
|
|
1.福建师范大学 地理科学学院;2.湿润亚热带生态地理过程省部共建教育部重点实验室;3.福建师范大学 地理研究所
|
|
| 摘要: |
| 对福建南部漳浦地区赤湖海岸沙丘(CH)和大澳海岸沙丘(CDS)近2 000年以来海岸风沙活动历史及其东亚冬季风(EAWM)的关系进行研究。在野外沙丘剖面沉积构造考察基础上, 通过光释光(OSL)测年技术重建研究区海岸风沙活动序列。结果表明: (1)漳浦海岸有近2 000年来发育的多期海岸风沙沉积, 其中, CH沙丘记录的风沙活动期分别为BC100–AD300年、AD500–AD870年、AD1050–AD1380年; CDS沙丘记录了AD200年左右、AD1040–AD1280年以及AD1410–AD1710年3个风沙活动期。(2)研究区海岸风沙活动期与我国东部海岸、东北亚及西北欧海岸风沙活动期大体一致。可能反映了近2 000年以来北半球气候环境发生了大范围的阶段性变化, 各个区域海岸风沙活动起止时间的不同, 反映了各地所处大气环流系统位置的分异或是地方性因素的差异。(3)东亚冬季风对福建南部沿海的风沙活动有明显影响。一般来讲, EAWM强盛时, 海岸风沙沉积比较活跃。虽然在最近2000年的冷暖期都有海岸风沙沉积, 但在暖期仅限于EAWM相对强盛的时期。EAWM影响范围广阔, 是东亚海岸风沙活动周期具有准同时性的基本驱动因素。此外, 北大西洋涛动(NAO)通过影响EAWM的强度驱动海岸风沙活动的阶段性发生, 因而对研究区海岸沙丘发育产生间接影响。本文讨论近2 000年以来季风区海岸沙丘演变序列及驱动机制, 可提取百年尺度上的海岸沉积古环境信息, 探讨东亚冬季风演化特征。 |
| 关键词: 海岸沙丘 光释光(OSL)测年 东亚冬季风 福建漳浦 |
| DOI：10.11759/hykx20161105001 |
| 分类号: |
| 基金项目:国家自然科学基金项目(41771020, 41271031, 41301012); 福建省自然科学基金项目(2017J01460); 福建师范大学地理科学学院研究生创新基金项目 |
|
| Episodes of coastal dune development over the last 2000 years on the south coast of Fujian |
|
XU Xiao-lin,LI Zhi-zhong,JIN Jian-hui,CHENG Yan,YU Xiao-li,LAI Hai-cheng,SHEN Jian-ling,YUAN Xiu-quan
|
| Abstract: |
| Extensive dunefields characterize part of the coastal areas in Fujian Province, indicating a history of aeolian activity that goes back thousands of years. In this study, coastal dune profiles (CH and CDS) were investigated in Zhangpu coast, south of the Fujian Province in China. We use optically stimulated luminescence (OSL) dating to reconstruct the coastal aeolian activity sequence of the study area. The results show that: 1) there are multi periods of coastal aeolian sediments developed in the Zhangpu coast in the last two millennia. The CH dune recorded the aeolian sand movement in three phases: between BC100 and AD300, between AD500 and AD870, and between AD1050 and AD1380; whereas the CDS dune recorded the movement around AD200, between AD1040 and AD1280, and between AD1410 and AD1710. 2) The periods of the aeolian sand activity in the study area is roughly consistent with that of the coast of eastern China, northeast Asia, and northwest Europe. It may reflect that a wide range of changes occurred in the Northern Hemisphere in the last two millennia. The reasons their starting and finishing times are different may be the difference of local factors. 3) The East Asian Winter Monsoon (EAWM) plays a significant role for aeolian processes of the southern coastal region of Fujian. Generally, when the EAWM is strong, the coastal aeolian deposits will be more active. Coastal aeolian deposits occurred in both cold and warm periods in the last two thousand years. But in the warm period, it is limited to the time that the EAWM is relatively strong. The EAWM has a large circle of influence, and it is the basic driving factor that the aeolian deposits activity in East Asia exhibits quasi-simultaneity. In addition, the North Atlantic Oscillation (NAO) has an indirect effect on the coastal dune development in the study area by affecting the intensity of the EAWM. |
| Key words: coastal dune optically stimulated luminescence (OSL) dating East Asian Winter Monsoon Zhangpu of Fujian Province |