Three-dimensional evolution of the Yangtze River mouth, China during the Holocene: impacts of sea level, climate and human activity
Three-dimensional evolution of the Yangtze River mouth, China during the Holocene: impacts of sea level, climate and human activity
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全新世中国长江口三维演化：海平面、气候和人类活动的影响
DOI：
10.1016/j.earscirev.2018.08.012
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发表时间：
2018-10
影响因子：
12.1
通讯作者：
Jiang X.
中科院分区：
文献类型：
--
作者：
Wang Z.;Saito Y.;Zhan Q.;Nian X.;Pan D.;Wang L.;Chen T.;Xie J.;Li X.;Jiang X.
由于最近相对海平面上升速度快和沉积物供应减少，中国长江三角洲海岸侵蚀的风险很高。对三角洲全新世演变的研究可以提供关于三角洲对海平面迅速上升和气候或人类活动造成的沉积物供应变化的反应的信息，尽管由于缺乏使用年龄限制的沉积记录的综合研究，这一点尚未得到充分探讨。在这里，我们记录了过去11,700年的地层结构和形态变化，并使用344个沉积物岩心，658个放射性碳和28个光释光（OSL）年龄的数据集估计了三角洲地区千年尺度上的沉积物量（其中我们获得了64个岩心、345个放射性碳年龄和28个光释光年龄，其他的我们来源于文献）。使用这个数据集，我们提出了时间和空间形态动力学演变的整个长江口从全新世早期海侵河口到全新世中期至晚期海退三角洲，使之有可能产生的沉积物沉积的定量和连续的分析。河口区的破坏阶段被确定为10至8卡尔。kyr BP，包括河口内的潮滩和槽以及近海的潮脊和槽地形的显著海岸侵蚀;这些是由于当时海平面快速上升造成的河口形态重塑。因此，河口的沉积物截留率从11.7-10 cal.的平均2.24亿吨/年下降。kyr BP到137 Mt yr− 1之间的10和8 cal. Kyr BP。自8000年前三角洲形成以来，水下三角洲发生了退缩，沉积物捕获率从8-6 cal.的1.51亿吨/年下降。kyr BP至99-113 Mt yr− 1，介于6和2 cal.之间。kyr BP，这是由与约6000年前夏季季风减弱有关的沉积物供应减少引起的。在过去的2000年中，由于人类活动的加剧，沉积物捕获率增加到1.62亿吨/年。三峡大坝建成后，三角洲现今的沉积水平（2003-2011年为49 Mt/a）远低于全新世的“自然”范围。因此，我们推断在不久的将来，在海岸侵蚀和过渡到一个新的平衡三角洲形态的系统政权转移的潜力。
The Yangtze (Changjiang) mega-delta, China, has a high risk of coastal erosion owing to the recent high rate of relative sea-level rise and reduced sediment supply. The study of the Holocene evolution of the delta can provide information about its response to rapid sea-level rise and changes in sediment supply caused by climate or human activity, although this has yet to be fully explored because of the lack of integrated studies using age-constrained sedimentary records. Here we document stratigraphic architecture and morphological changes over the last 11,700 years and estimate the amount of sediment trapped in the delta region on a millennial scale using a dataset of 344 sediment cores, 658 radiocarbon and 28 optically stimulated luminescence (OSL) ages (of which we obtained 64 cores, 345 radiocarbon and 28 OSL ages, and the others we sourced from the literature). Using this dataset we present the temporal and spatial morphodynamic evolution of the entire Yangtze River mouth from its early Holocene transgressive estuary to a mid- to late-Holocene regressive delta, making it possible to produce a quantitative and sequential analysis of sediment deposition. A destructive phase of the river mouth region was identified at 10 to 8 cal. kyr BP, including significant coastal erosion of tidal flats and troughs within the estuary and of tidal ridge-and-trough topography offshore; these resulted from the reshaping of the river mouth morphology caused by rapid sea-level rise at that time. As a result, the rate of sediment trapping at the river mouth declined from an average of 224 Mt yr−1at 11.7–10 cal. kyr BP to 137 Mt yr−1between 10 and 8 cal. kyr BP. Since delta initiation 8000 years ago, a retreat of the subaqueous delta occurred and the sediment trapping rate declined from 151 Mt yr−1at 8–6 cal. kyr BP to 99–113 Mt yr−1between 6 and 2 cal. kyr BP, caused by the reduction in sediment supply linked to summer monsoon weakening ~6000 years ago. In the last 2000 years the sediment trapping rate has increased to 162 Mt yr−1due to intensified human activity. The present-day level of sedimentation in delta (49 Mt yr−1in 2003–2011), after the completion of the Three Gorges Dam, is far lower than the ‘natural’ range in the Holocene. We thus infer a potential for system regime shift in terms of coastal erosion and a transition to a new equilibrium in delta morphology in the near future.
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影响因子：
2.9
作者：
Zhongyuan Chen;Y. Saito;K. Hori;Yiwen Zhao;A. Kitamura
通讯作者：
Zhongyuan Chen;Y. Saito;K. Hori;Yiwen Zhao;A. Kitamura
影响因子：
4
作者：
Y. Zong;Kangyou Huang;F. Yu;Zhuo Zheng;A. Switzer;Guangqing Huang;Ning Wang;Min Tang
通讯作者：
Y. Zong;Kangyou Huang;F. Yu;Zhuo Zheng;A. Switzer;Guangqing Huang;Ning Wang;Min Tang
影响因子：
3.9
作者：
Zhibing Feng;Baohua Liu;Yuexia Zhao;Li Xishuang;O. Dada;Li Jiang;Shaokun Si
通讯作者：
Zhibing Feng;Baohua Liu;Yuexia Zhao;Li Xishuang;O. Dada;Li Jiang;Shaokun Si
影响因子：
2.9
作者：
Ying Wang;Yongzhan Zhang;X. Zou;D. Zhu;D. Piper
通讯作者：
Ying Wang;Yongzhan Zhang;X. Zou;D. Zhu;D. Piper
DOI：
10.1016/j.palaeo.2015.09.006
发表时间：
2015-12
期刊：
Palaeogeography, Palaeoclimatology, Palaeoecology
影响因子：
--
作者：
K. N. Rao;Y. Saito;K. Nagakumar;G. Demudu;A. S. Rajawat;Sumiko Kubo;Zhen Li
通讯作者：
K. N. Rao;Y. Saito;K. Nagakumar;G. Demudu;A. S. Rajawat;Sumiko Kubo;Zhen Li