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Foreword

Advances in Polar Science 2022年第1期33卷 I0003-I0004页

作者： Jianfeng He Jianming Pan rujian wang Jiuxin Shi 不详

The Southern Ocean breeds a special *** evolution and adaptability of Antarctic marine organisms is a key research field of the Scientific Committee on Antarctic *** study of the Antarctic marine ecosystem is also one of the tasks of Chinese National Antarctic Research Expedition(CHINARE).However,the early investigations by Chinese scientists mainly focused on plankton and benthos,as well as their environmental *** 2019,financially supported by National Polar Special Program“Impact and Response of Antarctic Seas to Climate Change”(IRASCC),the research objects have been gradually expanded to large marine animal,such as birds and mammals,and other related disciplines.

关键词： Antarctic marine IRAS

Paleoenvironmental implications of Holocene long-chain n-alkanes on the northern Bering Sea Slope

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Acta Oceanologica Sinica 2017年第8期36卷 137-145页

作者： ZHANG Haifeng wang rujian XIAO Wenshen Laboratory of Marine Ecosystem and Biogeochemistry State Oceanic Administration State Key Laboratory of Marine Geology Tongji University

The records of high-resolution terrestrial biological markers （biomarkers） from Core B2-9 from the northern Bering Sea Slope over the last 9.6 ka BP were presented in the study. Variations in input of terrestrial long-chain n-alkanes （referred to as n-alkanes） and vegetation structure in their source regions were investigated. The results show that the nCz7 is the main carbon peak and has the greatest contribution rate of the total n-alkane content; this might be related to the abundance of woody plants and their spatial distribution in the source region, nC23 is another n-alkane having a relatively high content; this was mainly derived from submerged plants widespread along the coastal areas in the northern hemisphere. Total n-alkane content dropped quickly at ca. 7.8 ka BP, ca. 6.7 ka BP and ca. 5.4 ka BP, and was followed by four relatively stable stages mostly controlled by sea-level rise, climate change and vegetation distribution in the source region. Variation in carbon preference index （CPI） indicates that the n-alkanes primarily originated from higher land plants, and the average chain length （ACL） and nCa1/nC27 ratio reveal the relatively stable presence of woody/herbaceous plants during the Holocene, and dominate woody plants in most of the time. Simultaneous variation in total n-alkane content, nC27 content and its contribution, CPI, ACL and nC31/nC27 ratio over several short periods suggest that the growth rate of the woody plant n-alkane contribution was lower than that of herbaceous plants and fossil n-alkanes under the particular climatic conditions of the source region.

关键词： Bering Sea terrestrial input long-chain n-alkanes vegetation structure Holocene

Radiolarian biostratigraphy in the Southern Bering Sea since Pliocene

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Science China Earth Sciences 2014年第2期57卷 682-692页

作者： ZHANG Qiang CHEN MuHong ZHANG LanLan wang rujian XIANG Rong HU WeiFen Key Laboratory of Marginal Sea Geology South China Sea Institute of OceanologyChinese Academy of Sciences University of Chinese Academy of Sciences State Key Laboratory of Marine Geology Tongji University

Detailed radiolarian biostratigraphy in the Plio-Pleistocene was analyzed by using samples from IODP Site U1340 that was drilled to a core depth of 604 m in the southern Bering Sea.A total of 227 species belonging to 102 genera were *** on the distributions of the radiolarian index species at Site U1340,five radiolarian zones since the Pliocene were established in the southern Bering Sea for the first time,and 25 radiolarian bioevents were *** ages were estimated on the basis of the age-depth plot that was constructed by the synthetical datum of the effective biostratigraphic and magnetostratigraphic *** radiolarian zones at Site U1340 were systematically compared with those in its adjacent regions since the late Early Pliocene,which further improved and interpreted the biostratigraphic datum as well as their correlations in the middle-high latitude of the North *** addition,the comparative results of radiolarian zones show that Botryostrobus aquilonaris Zone emended in this paper is equivalent to the upper part of the same zone defined by Hays,1970,and Druppatractus irregularis-Dorydruppa bensoni Zone as well as Spongodiscus ***,newly proposed in this paper,are well correlated with Cycladophora sakaii Zone and Stylatractus universus Zone in the subarctic North Pacific,respectively.

关键词：生物地层学晚上新世放射虫白令海生物事件年龄估计北太平洋深度分析

Variations of opal accumulation rates and paleoproductivity over the past 12 Ma at ODP Site 1143, southern South China Sea

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Chinese Science Bulletin 2002年第7期47卷 596-598页

作者： Li Jianru wang rujian Li Baohua Laboratory of Marine Geology MEOTongji University200092ShanghaiChina Nanjing Institute of Geology and Paleontology Chinese Academy of Sciences210008NanjingChina

The biogenic silica analysis was performed on 463 samples from ODP 184 Site 1143, the southern South China Sea. The results show that the opal content and MAR evidently increased between 12.3 and 5.7 Ma, which was contemporary with the high carbonate and total MARs, reflecting the high biogenic productivity in the late Miocene. This demonstrates the occurrence of the late Miocene 'Biogenic Bloom Event' in the southern South China Sea, corresponding to the late Miocene-early Pliocene 'Biogenic Bloom Event' in the Indian-Pacific Ocean. The increases of opal content and MAR after the middle Pleistocene (about 0.7 Ma) is inferred to result from the enhanced upwelling and nutrient supply, which was induced by the intensified monsoon circulation after the 'Mid-Pleistocene Revolution'.

关键词： opal MAR biogenic productivity Biogenic Bloom Event late Miocene South China Sea.

The Mid-Pleistocene Climate Transition Recorded in a 1.6 Myr-Period Lacustrine Sediment Sequence from Mazatage, Tarim Basin

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Acta Geologica Sinica(English Edition) 2015年第1期89卷 312-313页

作者： LIU Jian WU Li wang rujian ZHAO Yue Institute of Geomechanics CAGS School of Ocean and Earth Science Tongji University

The mid-Pleistocene climate transition （MPT） has been widely reported in worldwide geological events. As a key issue of the Quaternary geology, it has attracted much attention from the paleoclimate community. MPT refers to a period lasting for several hundreds of thousand years, during which the dominant climate periodicity gradually extended from 41 kyr to 100 kyr （Ruddiman et al., 1989）,

关键词： wang Tarim Basin The Mid-Pleistocene Climate Transition Recorded in a 1.6 Myr-Period Lacustrine Sediment Sequence from Mazatage

Paleoceanographic records in the Chukchi Basin, western Arctic Ocean during the late Quaternary

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Acta Oceanologica Sinica 2012年第1期31卷 83-94页

作者： wang rujian XIAO Wenshen SHAO Lei CHEN Jianfang GAO Aiguo State Key Laboratory of Marine Geology Tongji UniversityShanghai 200092China Second Institute of Oceanography State Oceanic AdministrationHangzhou 310012China Department of Oceanography Xiamen UniversityXiamen 361005China

The late Quaternary paleoceanographic changes in the western Arctic Ocean are revealed by quan- titative studies of foraminiferal abundance, ice-rafted detritus （IRD） and its mineralogical and petrological compositions, planktonic Neogloboquadrina pachyderma （sin.）（Nps）-δ18O and -δ13C, biogenic and non-biogenic components in Core M03 token from the Chukchi Basin during the Sec- ond Chinese National Arctic Expedition cruise. Seven IRD events appeared at MIS 7, 5, 3 and 1. These IRD were carried in massive icebergs, which were exported to the Beaufort Sea through the M＇Clure Strait Ice Stream, Canadian Arctic Archipelago, and then transported into the Chukchi Basin by the Beaufort Gyre. Low IRD deposition occurred during the glacial times when more extended ice cover and weakened Beaufort Gyre, while the open water condition and the intensified Beaufort Gyre during interglacial periods favored the IRD deposition. Therefore, the IRD events not only indicate the provenance of coarser detritus and ice export events, but also reflect the evolutionary histories of the Beaufort Gyre and North American ice sheet. Seven light Nps-δ18O and -δ13C excursions could respond to enhanced rates of sea ice formation resulting in the pro- duction and sinking of isotopically light brines, but was irrelevant to the warm Atlantic water and freshwater inputs. Whereas, the heavy Nps-δ18O and -δ13C values separately reflect the lessened Arctic freshwater and Pacific water, and well-ventilated surface water from the continental shelf and halocline water. Variations of CaCO3 content and planktonic foraminiferal abundance during the interglacial and glacial periods can demonstrate the incremental or diminishing input of the Atlantic water, while the total organic carbon （TOC） and opal contents increased and decreased during the glacial and interglacial periods, respectively, which could be related to the TOC degradation, opal dissolution and redox conditions of interface between the bottom wat

关键词： IRD events ice sheet light Nps-δ18O and -δ13C excursions surface productivity late Quaternary Arctic Ocean Chukchi Basin

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莫高轶事——记莫高窟的园林绿化

敦煌研究 2024年第4期 33-36页

作者：孙儒僩敦煌研究院

看绿树成荫的林荫道相伴古老的石窟，就是如今莫高窟的景观，可是在八十多年前的莫高窟，树木稀疏，一片荒芜，直到1944年莫高窟被国家接管之后，在所长常书鸿的领导下进行了一系列有效管理，特别是重视对莫高窟园林的绿化，对已有的树... 详细信息

看绿树成荫的林荫道相伴古老的石窟，就是如今莫高窟的景观，可是在八十多年前的莫高窟，树木稀疏，一片荒芜，直到1944年莫高窟被国家接管之后，在所长常书鸿的领导下进行了一系列有效管理，特别是重视对莫高窟园林的绿化，对已有的树木倍加爱护，即便莫高窟搞修建需要木材，也去敦煌城购买，而不采伐窟前林木。同时又在窟前、河岸边、河对岸广种树木，有绿化树、亦有果树，为了让窟前常绿，又引进了敦煌以前从没有种植过的柏树，在长期的植树造林过程中，也在不断思索，不断更新，才造就了窟前林木花草的景观。真正是前人栽树，后人乘凉，如今开放的莫高窟广纳游人，置身窟前的林荫道中，惬意游玩。

关键词：莫高窟园林绿化绿树成荫

Late Quaternary ice-rafted detritus events in the Chukchi Basin, western Arctic Ocean

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Chinese Science Bulletin 2010年第4期55卷 432-440页

作者： wang rujian XIAO WenShen LI WenBao SUN YeChen State Key Laboratory of Marine Geology Tong/i University Shanghai 200092 China Alfred Wegener Institute for Polar and Marine Research Bremerhaven 2 7517 Germany

The late Quaternary ice rafted detritus (IRD) events in the Chukchi Basin, western Arctic Ocean are indications of the provenance of the coarser detritus and ice export events, and also document the evolutionary histories of Beaufort Gyre and the North American Ice Sheet (NAIS). The sediment of core M03 from the Chukchi Basin was selected to study the regional response to the ice export events and the NAIS variability. The stratigraphic framework of M03 was established by a combination of lithological features and downcore color change cycles, AMS14C dating with foraminifera abundance and IRD events. The core was also compared with the adjacent core NWR 5 from the Northwind Ridge area. The core extends back to Marine Isotope Stage (MIS) 7. A sedimentary hiatus of 10―20 ka might occur between 16 to 20 cm core depth. Seven IRD events are distinguished from the studied core and are presented during the early MIS 1, MIS 3, MIS 5 and late MIS 7. These IRD are transported by sea ice and icebergs, which were exported to the Beaufort Sea from the M'Clure Strait Ice Stream, Canadian Arctic Archipelago, and brought to the Chukchi Basin by the Beaufort Gyre.

关键词：盆地沉积物晚第四纪北冰洋粗碎屑事件西部管理信息系统 MIS系统

Radiolarian record to paleoecological environment change events over the past 1.2 MaBP in the southern South China Sea

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Chinese Science Bulletin 2002年第17期47卷 1478-1483页

作者： YANG Lihong CHEN Muhong wang rujian ZHEN Fan The South China Sea Institute of Oceanology Chinese Academy of SciencesGuangzhou 510301China Key Laboratory of Marine Geology Ministry of EducationTongji UniversityShanghai 200092China

This note studies the Radiolarian fossil groups since 1.2 MaBP in ODP leg 184 site 1143, the southern South China Sea (SCS). The result shows that radiolarian abundance experienced a significant variation: before 0.9 MaBP it remained at the extremely low level, but increased with low extent between 0.9-0.65 Ma, which corresponded to the Mid-Pleistocene Transition stage, and it increased rapidly after 0.65 MaBP. During the whole process, the average abundance became higher and higher in each stage, and showed regularly periodic fluctuations. The obvious increase after 0.65 MaBP is inferred to result from the enhanced up-welling in this region, which was induced by the intensified monsoon circulation after the 'Mid-Pleistocene Transition'. An outstanding result of the spectral analyses is that a long oscillation of - 0.2 Ma cycle was found in the records of radiolarian abundance and complex diversity, which corresponds well to the result of other paleoceanographic indexes. This probably indicated a

关键词： radiolarian southern South China Sea distribution environmental change site 1143.