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71.
Radiolarian record to paleoecological environment change events over the past 1.2 MaBP in the southern South China Sea 总被引:2,自引:0,他引:2
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
upwelling 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 special cycle characteristic of paleoecological environment evolution in this area. In addition, all of the radiolarian
indexes show an obvious boundary in about 0.47 MaBP, indicating the abrupt variation of the community structure and radiolarian
abundance level before and after 0.47 MaBP. So we suppose that there existed a distinct change event of oceanic ecology environment
during that period. 相似文献
72.
Carbon isotopic record of foraminifers in surface sediments from the South China Sea and its significance 总被引:3,自引:0,他引:3
CHENGXinrong WANGPinxian HUANGBaoqi LIUChuanlian JIANZhimin ZHAOQuanhong LIJianru TIANJun XUJian 《科学通报(英文版)》2005,50(2):162-166
Since the 1990s, the papers and data involved withthe South China Sea (SCS) have been emerging in largenumbers in the world as people pay more attention to thepaleoceanography of the SCS. There have been more than100 cores mentioned in papers containing p… 相似文献
73.
Linear sand ridges on the outer shelf of the East China Sea 总被引:3,自引:1,他引:3
WU Ziyin JIN Xianglong LI Jiabiao ZHENG Yulong WANG Xiaobo 《科学通报(英文版)》2005,50(21):2517-2528
Based on the latest full-coverage high-resolution multi-beam sounding data, the distribution of the linear sand ridges on the outer shelf of the East China Sea (ECS) is studied with quantitative statistical analysis. The study area can be divided into the northeastern part and the southwestern part. Sand ridges in the northeastern area, trending 116°N, show obvious linear character and shrink to the inner shell Sand ridges in the southwestern area, trending 120°N -146°N, tend to have net form. Sand ridges gradually become sand sheets in the center part of study area. Sand ridges are distributed landward to the isobath of 60m, distributed seaward to the water depth of 120 m in the northeast and 150 m in the southwest. Immature sand ridges are observed at water depth of 130-180 m in the southwestern depressions. The acoustic reflection properties of the internal high.angle inclined beddings of the sand ridges are analyzed based on the typical seismic profiles close to the research area. Lithological analysis and dating of 4 boreholes and 12 cores indicate that the widely distributed transgressive sand layer with high content of shell debris which was formed in the early-middle Holocene is the main composition of the linear sand ridges on the outer shelf of the ECS. The dominating factor in formation, developing and burying of the sand ridges is the variation of water depth caused by sealevel change and the rate of sediment supply. In 12400 aBP the cotidal lines of the M2 tidal component were closely perpendicular to the strike-directions of the sand ridges in the study area, and the tidal wave system during 12000-8000 aBP might play a key role in the formation of the linear sand ridges which are widely distributed on the outer shelf of the ECS. 相似文献
74.
旷新年 《杭州师范学院学报(社会科学版)》2005,(4)
莫言是新时期的重要作家,莫言的写作突破了当代文学的传统规范,具有一种革命性的意义。莫言的中篇小说《红高粱》既被视为“寻根文学”的终结,也被视为“新历史小说”的重要起源和代表作品。《红高粱》中人物描写的方法与当时有关人物性格复杂性的理论探讨有着密切的关联,反映了当代典型理论的重要变化和社会主义现实主义文学规范的崩溃及其对于创作的影响。《红高粱》和“新历史小说”的潮流与20世纪50年代《红旗谱》等“革命历史题材”小说的强大规范构成了明显的对话关系,其“情欲化的历史”和“迷宫般的历史”鲜明地体现了对“革命历史题材”小说的颠覆和重写。同时,《红高粱》的解读和“新历史小说”现象的命名与阐释本身也是一个在阐释中不断变化的过程。 相似文献
75.
Original component of grain size index in core sediment from southwestern slope of the South China Sea and its paleoenvironmental implication 总被引:1,自引:0,他引:1
CHEN Muhong ZHENG Fan LU Jun XIAO Shangbin YAN Wen CHEN Zhong XIANG Rong WEI Gangjian & ZHANG Lanlan . South China Sea Institute of Oceanology Chinese Academy of Sci- ences Guangzhou China . Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Correspondence should be addressed to Chen Muhong 《科学通报(英文版)》2005,50(9):896-902
Traditional grain size analysis was basically used to discriminate sediment type based on its particle dimension for sedimentary naming[1,2] and to analyze the dynamic feature of transport medium, including water current and wind strength[3―5]. Recently, some patency advances havebeen made by using different methods to separate different grain sizes in various original composition from sediments for searching a new way of paleoenvironmental study[6―8]. Grain size analysis is even playing an … 相似文献
76.
简述了生态脆弱性的概念,从自然和人为干扰两个方面分析了邛海流域的生态脆弱性特征及其成因,并对解决邛海流域的生态脆弱性问题提出了相关的建议。 相似文献
77.
玫瑰花色素的提取及其稳定性研究 总被引:14,自引:0,他引:14
库尔班江·巴拉提 《新疆师范大学学报(自然科学版)》2006,25(1):52-55
文章以玫瑰花为原料提取了玫瑰花红色素,并对其理化性质和稳定性进行了研究。结果表明,玫瑰花红色素用95%乙醇浸泡提取,提取率为7.3%。色素的水溶性好,对光、热、弱酸性至弱碱性介质及食品添加剂相当稳定,耐受一般的食品饮料加工条件。色素对氧化剂H2O2的耐受能力较弱,而对还原剂N aHSO3则较为稳定。玫瑰花红色素是一种提取工艺简单、性质稳定、颜色鲜艳、价廉易得、来源充足的天然色素,可用于有色糖果、食品、果汁饮料、茶饮料及酒类。 相似文献
78.
PAN Aijun WAN Xiaofang XU Jindian GUO Xiaogang LI Li 《科学通报(英文版)》2006,51(4):472-479
A VERTICALLY UNIFORM LAYER OF TEMPERATURE(ISOTHERMAL LAYER),SALINITY(ISOHALINE LAYER)AND DENSITY(MIXED LAYER)IS USUALLY FORMED IN THE UPPER OCEAN DUE TO THE WIND STIRRING.UNDERNEATH IS THE LAYER WITH RELATIVELY STRONG VERTICAL GRADIENT AS THE THERMOCLINE,… 相似文献
79.
动力学分光光度法测定海盐中的痕量碘 总被引:1,自引:0,他引:1
在硫酸介质中,基于高碘酸钾氧化碘离子生成碘,进而使次甲基蓝褪色的反应,建立了测定痕量碘的新方法,线性范围为0μg/mL-7.2μg/mL,检出限为0.33μg/mL。方法简便、灵敏、选择性好,用于海盐中痕量碘的测定,结果满意。 相似文献
80.
The 1997–1998 warm event in the South China Sea 总被引:3,自引:0,他引:3
A strong warm event happens during spring 1997 to spring 1999 in the South China Sea. Its intensity and duration show that it is the strongest event on the record over the past decades. It also corresponds with the severe flood over the valley of the Yangtze River and a couple of marine environmental events. This note addressed the evolution process by using several data sets, such as sea surface temperature, height and wind stress in addition to subsurface temperature. The onset of the warm event almost teleconnects with the El Niño event in the tropical Pacific Ocean. Summer monsoon is stronger and winter monsoon is weaker in 1997 so that there are persistent westerly anomalies in the South China Sea. During the development phase, the warm advection caused by southerly anomalies is the major factor while the adjustment of the thermocline is not obvious. Subsequently, the southerly anomalies decay and even northerly anomalies appear in the summer of 1998 resulting from the weaker than normal summer monsoon in 1998 in the South China Sea. The thermocline develops deeper than normal, which causes the downwelling pattern and the start of the maintaining phase of the warm event. Temperature anomalies in the southern South China Sea begin to decay in the winter of 1998–1999 and this warm event ends in the May of 1999. 相似文献