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Distribution, burial fluxes and carbon sink effect of sedimentary organic carbon in the eastern China seas

Science China Earth Sciences 2024年第10期67卷 3062-3082页

作者： Xuefa SHI Bin WU Shuqing QIAO Zhengquan YAO Limin HU Yazhi BAI Shan HU Jie SHENG Yanguang liu shengfa liu Kunshan WANG Jianjun ZOU Key Laboratory of Marine Geology and Metallogeny First Institute of Oceanography Ministry of Natural Resources Laboratory for Marine Geology Qingdao Marine Science and Technology Center Key Laboratory of Deep Sea Mineral Resources Development Shandong Province (Preparatory) Key Laboratory of Submarine Geosciences and Technology College of Marine Geosciences Ocean University of China

The ocean is the largest active carbon reservoir on Earth. Organic carbon（OC）, as the primary species of carbon sequestration in the ocean, plays an important role in the global carbon cycle through its deposition and burial. In this study,sedimentary OC data from 5796 stations, together with relevant geochemical and sedimentological parameters in the Bohai Sea,Yellow Sea, and East China Sea（BYES） were used to summarize and elucidate the distribution and burial patterns of sedimentary OC, and assess carbon sink effect of sedimentary OC burial. The results show that the OC content in the sediments of the BYES ranges from 0.00% to 2.12%, with an average content of 0.47%±0.26%. OC content is significantly correlated with finegrained sediments, with an average OC content in mud areas being 39% higher than that in non-mud areas. Modern OC buried in the BYES are mainly deposited in 7 major mud areas, with a total sedimentary OC burial flux of approximately 8.20 Mt C yr–*** them, the burial flux of biospheric OC is 6.92 Mt C yr–1, equivalent to the OC consumption amount of silicate weathering of the 9 major river basins in the eastern China. In its natural state, the annually sequestered OC in the sediments of the eastern China seas is equivalent to 25.37 Mt of atmospheric CO2, indicating a significant carbon sink effect. The distribution and burial of terrigenous OC in the BYES are mainly influenced by the large river inputs and complex marine hydrodynamic environment,while human activities such as dam construction have significantly altered the OC burial in these coastal mud areas.

关键词： Sedimentary organic carbon Burial flux Carbon sink effect Carbon cycle Eastern China seas

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Major and trace element geochemistry of the mid-Bay of Bengal surface sediments: implications for provenance

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Acta Oceanologica Sinica 2017年第3期36卷 82-90页

作者： LI Jingrui liu shengfa FENG Xiuli SUN Xingquan SHI Xuefa College of Marine Geosciences Ocean University of China Key Laboratory of Marine Sedimentology and Environmental Geology The First Institute of OceanographyState Oceanic Administration Laboratory for Marine Geology Qingdao National Laboratory for Marine Science and Technology

The major and trace elements in 110 surface sediment samples collected from the middle of the Bay of Bengal（mid-Bay of Bengal） are analyzed to investigate provenance. Si levels are highest, followed by Al, and the distributions of these two elements are identical. The average CIA＊（chemical index of alteration） value is 72.07,indicating that the degree of weathering of the sediments in the study area is intermediate between those of sediments of the Himalayan and Indian rivers. Factor analyses and discrimination function analyses imply that the two main provenances are the Himalayan and the Indian continent. The inverse model calculation of the Tinormalized element ratios of the Bay of Bengal sediments indicate an estimated average contribution of 83.5%and 16.5% from the Himalayan and peninsular Indian rivers to the study area, respectively. The Himalayan source contributes more sediment to the eastern part of the study area, whereas the western part receives more sediment from the Indian Peninsula than did the eastern part. The primary mechanisms for deposition of sediments in the study area are the transport of Himalayan matter by turbidity currents and river-diluted water and the transport of Indian matter to the study area by a surface circulation in the Bay of Bengal, particularly the East India Coastal Current.

关键词： major and trace element Bay of Bengal provenance quantification factor analyses

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基于孟德尔随机化研究肠道菌群与缺血性脑卒中的因果关系

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中国微生态学杂志 2024年第8期36卷 892-899,906页

作者：汪鸣刘生发张滋龙钱燕安彩莲张永茂费国娟河西学院附属张掖人民医院康复医学科甘肃张掖734000 甘州区妇幼保健院妇产科

目的采用两样本孟德尔随机化法(Mendelian randomization,MR)分析肠道菌群与缺血性脑卒中(ischemic stroke,IS)发病风险的因果关联。方法肠道菌群汇总数据来自MiBio-Gen联盟进行的全基因组关联荟萃分析资料;IS数据来自IEU Open GWAS数... 详细信息

目的采用两样本孟德尔随机化法(Mendelian randomization,MR)分析肠道菌群与缺血性脑卒中(ischemic stroke,IS)发病风险的因果关联。方法肠道菌群汇总数据来自MiBio-Gen联盟进行的全基因组关联荟萃分析资料;IS数据来自IEU Open GWAS数据库。采用逆方差加权法、MR-Egger法、加权中值法、简单众数法及加权众数法研究肠道菌群与IS之间的因果关联。以OR(95%CI)值评价肠道菌群对IS发病风险的因果关系。采用MR-PRESSO和MR-Egger回归分析检验多效性,Cochran's Q检验评估工具变量的异质性。“留一法”分析评估每个单核苷酸(single nucleotide polymorphism,SNPs)对结局的影响。结果从门、纲、目、科、属五个水平对211种肠道菌群与IS进行因果关联性分析结果表明,Lentisphaerae、Clostridia、Clostridiales、Clostridiaceae1、Barnesiella、Intestinimonas、LachnospiraceaeNK4A136group及Lachnospiraceae FCS020 group与IS的发病呈负相关,而Allisonella、Paraprevotella及Streptococcus与IS的发病呈正相关。经过Bonferroni方法进行多重校正后,发现Clostridiaceae1与IS具有显著因果关系。MR-PRESSO和MR-Egger回归分析显示不存在多效性(P>0.05),Cochran's Q检验结果表明不存在异质性(P>0.05),“留一法”分析显示结果稳定。结论肠道菌群与IS的发病存在因果关系,Lentisphaerae、Clostridia、Clostridiales、Clostridiaceae1、Barnesiella、Intestinimonas、Lachnospiraceae NK4A136 group及Lachnospiraceae FCS020 group可能是IS的保护因素,而Allisonella、Paraprevotella及Streptococcus可能是IS的危险因素,其中Clostridiaceae1能显著降低IS的发病风险。

关键词：孟德尔随机化肠道微生物缺血性脑卒中因果关系

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Distribution of major and trace elements in surface sediments of Hangzhou Bay in China

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Acta Oceanologica Sinica 2012年第4期31卷 89-100页

作者： liu shengfa liu Yanguang YANG Gang QIAO Shuqing LI Chaoxin ZHU Zhiwei SHI Xuefa First Institute of Oceanography State Oceanic AdministrationQingdao 266061China Key Laboratory of Marine Sedimentology and Environmental Geology State OceanicAdministrationQingdao 266061China

The Inductively Coupled Plasma Optical Emission Spectrometer was used to analyze sediment samples collected from the Hangzhou Bay to determine major and trace elemental concentrations. Based on these concentrations, the study area can be classified into three geochemical provinces. Province I covers the northern Hangzhou Bay area and contains high concentrations of A120~, Fe203, MgO, Na20, K20, MnO, Cr, Cu, Ni, Pb, V, Co and Zn. Province III is located in the western Hangzhou Bay, near the Qiantang River mouth, and contains high concentrations of SiO~, Na20, P205~ TiO2, Cr, Sr, Zr. Province II is located in the middle and eastern Hangzhou Bay, with the medium concentrations of major and trace elements. The results also demonstrate that the grain size is the dominating factor controlling the spatial variations of elemental concentrations, and the Changjiang River （Yangtze River） and Qiantang River sediments play an important role in the distribution of these elements. Anthropogenic impact on heavy metal concentrations （especially Cr, Sr and Zr） can be detected in the surface sediments near the Qiantang River mouth.

关键词： Hangzhou Bay Changjiang River sediments major and trace elements grain size,heavy metals

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Refinement Role of Electromagnetic Stirring and Calcium in AZ91 Magnesium Alloy

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Journal of Wuhan University of Technology(Materials Science Edition) 2008年第2期23卷 194-197页

作者： HAN Hui liu shengfa KANG liugen liu Linyan (School of Materials Science and Engineering,Wuhan University of Technology,Wuhan 430070,China) School of Materials Science and Engineering Wuhan University of Technology Wuhan China

Effects of calcium addition and electromagnetic stirring on the microstructure of AZ91 magnesium alloy and refinement mechanism were *** results show that calcium addition ranging from 0.1wt% to 0.3 wt% does not lead to formation of any new phases but cause the refinement of as- cast ***,combined calcium alloying and electromagnetic stirring significantly decrease the grain size,change the morphologies of theβ-Mg17Al12phases,and reduce their volume *** minimum grain size of AZ91 alloy is obtained in the case of the addition of 0.2 wt%Ca with exciting voltage of 100 *** microstructural refinement is attributed to the increase of the degree of undercooling and nucleation temperature of primaryα-Mg phases on the basis of DTA analysis results.

关键词： AZ91 magnesium alloy electromagnetic stirring calcium microstructural refinement

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90 kaBP以来阿拉伯海中部海域沉积物来源及沉积过程

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海洋地质与第四纪地质 2024年第2期44卷 146-156页

作者：陶菁刘升发艾丽娜曹鹏黄牧张辉吴凯凯齐文菁方桐冰孟元库石学法山东科技大学地球科学与工程学院青岛266590 自然资源部第一海洋研究所海洋地质与成矿作用重点实验室青岛266061 青岛海洋科技中心海洋地质过程与环境功能实验室青岛266237 中国海洋大学海洋地球科学学院青岛266100

通过对阿拉伯海中部AS06-13岩芯的地球化学特征、黏土矿物组成特征分析,结合有孔虫壳体AMS14C年龄和氧同位素数据建立的年代框架,探讨了阿拉伯海中部海域沉积物的来源及沉积过程。结果显示:AS06-13岩芯涵盖了阿拉伯海90 kaBP以来的沉积... 详细信息

通过对阿拉伯海中部AS06-13岩芯的地球化学特征、黏土矿物组成特征分析,结合有孔虫壳体AMS14C年龄和氧同位素数据建立的年代框架,探讨了阿拉伯海中部海域沉积物的来源及沉积过程。结果显示:AS06-13岩芯涵盖了阿拉伯海90 kaBP以来的沉积序列,平均沉积速率为2.34 cm/ka;稀土元素含量为64~194μg/g,平均值为114μg/g,δEu(平均值为0.71)负异常显著;黏土矿物主要由伊利石(平均含量为56%)、坡缕石(平均含量为18%)、绿泥石(平均含量为15%)、高岭石(平均含量为8%)和蒙脱石(平均含量为2%)组成。球粒陨石标准化的稀土元素配分曲线表现为轻稀土元素富集,重稀土元素亏损的右倾模式,表明研究区沉积物以陆源碎屑为主,通过δEuUCC-(La/Yb)UCC判别图进一步将90 kaBP以来阿拉伯海中部海域沉积物来源变化划分为3个阶段:S1阶段(90~73 kaBP)研究区主要接受印度河入海物质和阿拉伯半岛风尘物质的输入;S2阶段(73~11 kaBP)仍然以印度河和阿拉伯半岛风尘的物质输入为主,但逐渐受到印度半岛的片麻岩区物质的影响;S3阶段(11~0 kaBP)主要接受来自印度河的河流沉积物、阿拉伯半岛风尘、印度半岛的片麻岩区和德干高原物质的共同沉积。坡缕石含量和高岭石/伊利石比值指示90 kaBP以来阿拉伯海中部海域沉积物的陆源物质输入和沉积演化主要受季风和海平面的共同控制,西南季风的减弱和海平面下降导致印度河、德干高原物质对研究区的输入量增多,东北季风的增强和西北风相对增强使阿拉伯半岛的风尘输入增加;全新世海平面快速上升使输入阿拉伯海的河流沉积物急剧减少。

关键词：沉积物稀土元素黏土矿物物源沉积过程阿拉伯海

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Environmental record from the mud area on the inner continental shelf of the East China Sea since the mid-Holocene

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Acta Oceanologica Sinica 2011年第4期30卷 43-52页

作者： liu shengfa SHI Xuefa liu Yanguang WU Yonghua YANG Gang First Institute of Oceanography State Oceanic Administration Qingdao 266061 China Key Laboratory of Marine Sedimentology and Environmental Geology State OceanicAdministration Qingdao 266061 China

Paleoclimate record was revealed in Core MZ01 covering the mid-Holocene in age,located in the mud area of the inner continental shelf of the East China Sea. The ancient environment featured low-energy shallow sea shelf deposition formed mainly by coastal currents. The results show that temporal variation in geochemistry corresponds with the climate changes inferred from historical record. Relatively low MgO/Al 2 O 3,CaO/K 2 O and high Al 2 O 3 /Na 2 O,K 2 O/Na 2 O,MnO/CaO values reflected a warm and humid climate in general,and vice versa. Therefore,these chemical indices could be applied to identify the variation of palaeoclimate in eastern China. The authors reconstructed the history of mid-Holocene climatic variation of the inner continental shelf of the East China Sea. From 8 300 a BP to 4 200 a BP,the climate was moderately warm and humid. From 4 200 a BP to 2 000 a BP,the climate turned cool and dry,and the regional climate frequently fluctuated in alternation of cool-dry periods（3 700 a BP,2 850 a BP and 2 400 a BP） and warm-wet periods（3 250 a BP and 2 650 a BP） . After 2 000 a BP,the climate of the study area gradually turned warm again,while the Little Ice Age,a cold event centered at around 250 a BP was indicated by those geochemical indices as mentioned above.

关键词： Holocene East China Sea mud area major element palaeoclimate East Asia monsoon

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Clay mineral composition and their sources for the fluvial sediments of Taiwan Residents rivers

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Chinese Science Bulletin 2012年第6期57卷 673-681页

作者： LI ChuanShun SHI XueFa KAO ShuhJi CHEN MinTe liu YanGuang FANG XiSheng LUE HuaHua ZOU JianJun liu shengfa QIAO ShuQing First Institute of Oceanography State Oceanic AdministrationQingdao 266061China Research Center for Environmental Changes Academia SinicaTaipei 11529China Institute of Applied Geosciences Taiwan Ocean UniversityKeelung 20224China

Located at the collision boundary between the Philippine Sea Plate and the Eurasian Continental Plate,the island of Taiwan is generally recognized as an important example in the MARGINS Program Science Plan and "source-to-sink" research because of its high tectonic activity,heavy rainfall and unique *** suspended sediment loads are transported to the adjacent ocean by Taiwan Residents rivers every year,making Taiwan an important source of sediments into the adjacent seas and a natural laboratory for studying the systemic movement of fluvial sediments from source to sink.A detailed study on the clay mineral composition of surface sediments collected from the drainage basins of 12 Taiwan Residents rivers using X-ray diffraction methods was *** results indicated that the clay mineral assemblages consisted dominantly of illite(approximately 73%) and chlorite(approximately 24%),with lesser abundances of kaolinite(approximately 3%) and even lower levels of smectite from the Danshuei River sediments in northwestern *** Jhuoshuei River sediments from western Taiwan contained clay mineral assemblages that consisted of illite(approximately 75%) and chlorite(approximately 25%),but they lacked kaolinite and *** southwestern Taiwan,the clay mineral assemblages were dominated by illite(approximately 75%) and chlorite(approximately 23%),but had a low abundance of kaolinite(generally < 2%) and no *** clay mineral assemblages in eastern Taiwan are obviously different from those in western parts of the *** most noticeable difference is that the average abundance of chlorite in the Hualien River from eastern Taiwan was the highest(approximately 48%) of all the Taiwan Residents *** concluded that,in general,the clay mineral assemblages in Taiwan Residents rivers were mainly composed of illite and chlorite with kaolinite and smectite being scarce,and these trends are different from those in China's mainland *** clay miner

关键词：河流沉积物粘土矿物矿物组成台湾岛 X射线衍射方法矿物组合表层沉积物菲律宾海板块

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The biogenic silica variation and paleoproductivity evolution in the eastern Indian Ocean during the past 20 000 a

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Acta Oceanologica Sinica 2019年第1期38卷 78-84页

作者： Yonghang Xu Liang Wang Zhikun Lai Xiaohui Xu Feng Wang shengfa liu Xuefa Shi Rainer Arief Troa Rina Zuraida Eko Triarso Marfasran Hendrizan Laboratory of Ocean and Coast Geology Third Institute of Oceanography Ministry of Natural Resources Laboratory for Marine Geology Pilot National Laboratory for Marine Science and Technology (Qingdao) Key Laboratory of Marine Sedimentology and Environmental Geology First Institute of Oceanography Ministry of Natural Resources Marine Research Center Agency of Research and Human Resources for Marine and Fisheries Marine Geological Institute Agency for Research and Development for Energy and Mineral Resources Research Center for Geotechnology Indonesia Institute of Sciences

The biogenic silica of sediment samples from Core CJ01-185 which is collected from the eastern India Ocean off the Sunda Strait is analyzed to evaluate the impact of the opening of the Sunda Strait on a paleoproductivity evolution. The new results indicate that the biogenic silica mass values of Core CJ01-185 show the lowest 0.86% in the last glacial period, and reach its maxima of 1.89% in the late Holocene. Furthermore, the biogenic silica mass accumulation rate(MARBSi) values also vary with much higher during the late Holocene than during the last glaciation. The input of additional terrigenous materials from the Java Sea has enhanced the paleoproductivity and increased the biogenic silica mass and MARBSi values after the opening of the Sunda Strait. It is suggested that the paleoproductivity in the study area is mainly influenced by the southeast monsoon and upwelling before the opening of the Sunda Strait. However, the paleoproductivity is dominated by the terrigenous materials input other than by the southeast monsoon or upwelling in the Holocene.

关键词： biogenic silica paleoproductivity Sunda Strait eastern India Ocean

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Records of the East Asian winter monsoon from the mud area on the inner shelf of the East China Sea since the mid-Holocene

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Chinese Science Bulletin 2010年第21期55卷 2306-2314页

作者： liu shengfa SHI XueFa liu YanGuang QIAO ShuQing YANG Gang FANG XiSheng WU YongHua LI ChaoXin LI XiaoYan ZHU AiMei GAO JingJing Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China Key Laboratory of Marine Sedimentology and Environmental Geology First Institute of Oceanography State Oceanic Administration Qingdao 266061 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

AMS14C dating and analysis of grain size,major elements and clay minerals were applied to Core MZ01 from the mud area on the inner shelf of the East China *** on the environmentally sensitive grain size,clay mineral and major element assemblages,the history of the East Asia winter monsoon since the mid-Holocene could be *** three proxies,mean grain size(>9.71μm),chemical index of alteration(CIA)and ratio of smectite to kaolinite in particular,show similar fluctuation patterns. Furthermore,10 extreme values corresponding to the contemporary cooling events could be recognized since the mid-Holocene;these extreme values are likely to have been caused by the strengthening of the East Asia winter *** cooling events correlated well with the results of theδ18O curves of the Dunde ice core and GISP2,which therefore revealed a regional response to global climate *** stages of the East Asia winter monsoon were identified,i.e.8300-6300 a BP,strong and unstable;6300-3800 a BP,strong but stable;3800-1400 a BP,weak and unstable;after 1400 a BP,weak but stable.

关键词：东亚冬季风中全新世 Sea 内陆架中期中国亚洲面积

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