# Correlations Between Biogenic Components and Dust Input and Their Change Mechanism on Hess Rise, Central North Pacific, During the Late Quaternary*

You Defang, Wang Rujian*, Xiao Wenshen

State Key Laboratory of Marine Geology, Tongji University, Shanghai 200092, China

First author: You Defang(1992-), male, Qingdao City, Shandong Province, Master student. Research areas include polar paleoceanography and micropaleontology. E-mail: dfyou@tongji.edu.cn

Abstract

The study of marine export production is helpful to trace the changes of oceanic and global carbon reservoirs. Dust input is an important factor inspiring marine export production. Measurements of carbonate, Opal, TOC and Corg/N were performed on Core SO202-37-2, which was retrieved from Hess Rise, central North Pacific during the German SO202-INOPEX Expedition, for reconstructing variations of the local export production and dust input. The core age model is constructed via morphologically correlating its foraminifer oxygen isotope record with those of Core H3571 and the LR04 stack. XRF-Ti/Ca can be used as a proxy for dust input and its distribution pattern is consistent with that of Opal content, possibly indicating that dust input may have affected the local export production, i.e. the local export production increased (decreased) with enhancing (declining) dust input during interglacial (glacial) periods. Fluctuations in dust input might be due to southward/northward migration of the Westerly Jet over the dust source regions during interglacial and glacial periods. Although global dust output increased during glacial periods, meridional migration of the Westerly Jet in this area made the distribution pattern of the dust deposition in the study area different from that of other areas.

Keywords： North Pacific Hess Rise ; Biogenic components ; Marine export production ; Dust input ; Westerly Jet.

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You Defang, Wang Rujian, Xiao Wenshen. Correlations Between Biogenic Components and Dust Input and Their Change Mechanism on Hess Rise, Central North Pacific, During the Late Quaternary*[J]. Advances in Earth Science, 2018, 33(11): 1203-1214 https://doi.org/10.11867/j.issn.1001-8166.2018.11.1203.

## 1 引 言

Fig.1   Map of climatic and oceanographic settings in the North Pacific showing locations of sites SO202-37[9]at Hess Rise (this study), H3571[5], ODP882[10] and V21-146[11] and fronts, surface currents[12,13] and atmospheric circulation[[14]
Dark blue lines show respectively subarctic and subtropical fronts, red dashed lines with arrows show warm surface currents, black dashed lines with arrows show cold surface currents, dark blue arrow shows westerly wind and light blue arrow shows East Asian winter monsoon

## 3 材料与方法

### 3.1 材料来源

SO202-37-2孔沉积物样品由德国R/V Sonne号科学考察船于2009年SO202-INOPEX航次采集,岩芯长24.35 m,本文仅研究该岩芯0~251 cm深度的样品,以3 cm为间隔取样,共取得84个样品。该段岩芯沉积物以褐色、黄色粉砂质黏土以及灰白色、浅灰色粉砂质黏土为主要特征,其中0~19 cm为黄色,19~60 cm为褐色,60~180 cm 为浅灰色—灰白色旋回,180~251 cm呈黄褐色[9]。该站位与西北太平洋对比站位信息见表1[5,9,11,15]

Table 1   Information for the sites in central and western North Pacific

SO202-3737°46.07'176°16.13'3 658[9](本文)
H357134°54.25'179°42.18'3 571[5]
V21-12637°41'163°02'3 968[11]
ODP88250°21'167°35'3 244[15]

### 3.2 研究方法

XRF元素含量扫描:使用Avaatech XRF岩芯扫描仪在1 cm分辨率下进行元素含量无损扫描,分别在15,30和50 kV电压下扫描3次,得到多种元素(Al-Ba)的相对含量,数据单位分别是counts/10 s,counts/15 s和counts/30 s[18]

CaCO3测试:取小于0.1 g的CaCO3标样置于二氧化碳真空气压泵中,使其与体积比为1∶ 3的稀盐酸反应,记录产生的气压值,测试标样至少3组,可得标准工作曲线。取0.1 g左右研磨好的干样放于容器中进行测量,通过产生的二氧化碳体积,经过计算得到样品中碳酸盐的百分含量[22]

## 4 结 果

### 4.1 浮游有孔虫氧同位素变化

Fig.2   Chronostratigraphic framework of Core SO202-37-2 from the Hess Rise, central North Pacific, assigned with marine isotope stages (MIS), stratigraphic correlations between LR04 stack[24] and Cores SO202-37-2 and H3571[5] based on foraminiferal oxygen isotope

### 4.2 地层年代框架

Table 2   Age control points of Core SO202-37-2 from the Hess Rise, central North Pacific

/cm

/ka

/cm

/ka
16.51/214169.55b(谷底)87
37.52/329208.55d(谷底)109
118.53/457235.55/6130
148.54/571

Fig.3   Age model and sedimentation rate of Core SO202-37-2 from the Hess Rise, central North Pacific
Black dots are depth-age control points, and dashed lines are extrapolated trendlines

### 4.3 生源组分特征

CaCO3含量变化范围为50%~79%,平均值为62.2%(图4)。MIS 6~5c期CaCO3含量呈下降趋势,其中MIS 5c和5e期内分别出现2个高值;MIS 5c晚期至MIS 5a晚期CaCO3含量先快速上升后逐渐下降,高值71.89%出现在5b期内;MIS 5a晚期至MIS 2晚期CaCO3含量同样先上升后下降,MIS 3早期(约55 ka) 达最高值79%;MIS 2晚期之后快速上升。CaCO3含量整体呈现出间冰期减小,冰期增大的特点,要注意的是,这里所说的减小不是低值的意思,而是一种变化趋势,因为CaCO3含量极大值都出现在冰期/间冰期界线附近。

Fig.4   Variation in percentage of biogenic components of Core SO202-37-2 from the Hess Rise, central North Pacific

TOC含量整体较低,变化范围为0.17%~0.64%,平均值仅为0.34%。MIS 6期至MIS 5a早期,TOC含量在0.3%上下波动;MIS 5a期明显上升,MIS 5a晚期(68~70 ka)达最大值0.64%,且高于表层TOC含量;进入MIS 4期,TOC含量快速下降;MIS 3期至MIS 2晚期,TOC含量缓慢上升,MIS 2晚期快速下降。TOC含量的变化趋势与Opal含量变化一致,呈现出间冰期增大,冰期减小的特点。Corg/N的平均值为6.7,峰值几乎与TOC含量峰值一致,MIS 5a晚期至MIS 4早期Corg/N值较高,其他时期基本在平均值上下波动。

### 4.4 陆源组分特征

Fig.5   Variations in Ti/Ca, Al/Ca, Fe/Ca ratios and Ti, Al, Fe content in comparison with percentage of Opal in Core SO202-37-2 from Hess Rise, central North Pacific

Fig.6   Linear relationship of Ti/Ca, Al/Ca, Fe/Ca ratios with percentage of Opal in Core SO202-37-2 from Hess Rise, central North Pacific

## 5 讨 论

### 5.2 海洋生产力变化

Fig.7   Linear relationship of Ti/Ca ratio, percentages of Opal, CaCO3 and TOC in Core SO202-37-2 from Hess Rise, central North Pacific

Corg/N值可以作为判断海洋沉积物来源的有效指标,海源有机质中浮游植物的Corg/N值为6~7[41,42],沉积物中海源有机质的Corg/N值为8~9[43],而陆源有机质的Corg/N值为20~200[44]。由Corg/N值可以看出(图4),除MIS 5a/MIS 4期界线,Corg/N值达12,可能反映有机质是混合来源之外,其他时期Corg/N值在6~8变化,说明海源沉积是有机质的主要来源;而MIS 5a/MIS 4期界线出现较高的Corg/N值,可能与粉尘带入较多的陆源有机质有关。

### 5.3 北太平洋中西部粉尘输入对比

Fig.8   Comparison of dust input in Greenland ice core[45] and in Cores SO202-37-2, ODP882[15], H3571[5] and V21-146[11]

### 5.4 西风带移动与粉尘输出变化

Fig.9   The location of Westerly Jet in East Asian and the North Pacific during winter and summer[14,46]
Remote sensing image comes from http:∥search-image.tianditu.com

## 6 结 论

(1) 通过该孔浮游有孔虫G. inflata,G. bulloides18O与H3571孔G. inflata18O和深海氧同位素曲线LR04-δ18O进行对比,建立了该站位的年代地层框架,底部年龄141.7 ka,为MIS 6期以来的沉积记录,平均沉积速率为1.8 cm/ka。

(2) XRF-Ti/Ca值可以作为粉尘输入强度的替代性指标,MIS 5e晚期、MIS 5c晚期、MIS 4早期以及MIS 3晚期Ti/Ca值出现高值,说明粉尘输入的明显增多。粉尘输入整体呈现出冰期减小,间冰期增大的特点。

(3) 生物硅含量与Ti/Ca值显著相关,在MIS 5e/5d期界线、MIS 5c/5b期界线、MIS 5a/4期界线以及MIS 3晚期生物硅含量出现高值,整体呈现冰期减小,间冰期增大的特点。陆源粉尘输入量增加,促进了表层硅藻等硅质生物的繁盛,即初级生产力的提高,可能是由于粉尘中含有Fe这一刺激因子,在营养物质充足的条件下,促进了浮游植物的繁盛。

(4) 西风环流是粉尘传输的主要机制,北太平洋中部地区明显受西风急流的控制。冰期时西风急流较间冰期整体偏南,远离黄土高原、塔里木盆地等物源区,使得粉尘输出减少,而间冰期西风急流经过物源区,使得该区粉尘输出增多,从而导致海洋生产力提高。尽管冰期时全球粉尘输出是增多的,但是在北太平洋中部地区由于西风急流位置的变化,使得粉尘沉积记录与其他地区不完全相同。

The authors have declared that no competing interests exist.

## 参考文献 原文顺序 文献年度倒序 文中引用次数倒序 被引期刊影响因子

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Cross-spectral analysis of down-core variations in planktonic δ18O values correlates well with the SPECMAP reference scale allowing recognition of marine isotope stages (MIS) down to MIS 10 and the δ18O variations coincide well with the changes in sea surface temperature derived using the modern analogue technique. Time-series analyses of mass accumulation rates (MAR) of planktonic and benthic foraminifera were also performed along with analysis of variations in faunal composition. MAR of planktonic foraminifera display maxima during glacial periods which, together with coincident changes in lightness (L*) of sediment measured with the spectrophotometer, strongly suggests increasing flux of eolian dust to the Hess Rise due to strengthened westerly winds. However, MAR of benthic foraminifera including Epistominella exigua, a common typical phytodetritus feeder, also display highest increases during some interglacial periods (i.e. MIS 5 and 7). The benthic MAR maxima are thought to reflect variations in consumption patterns between benthic and planktonic species. A proposed hypothesis that vigorous grazing of phytoplanktons occurred during glacial periods reducing the flux of phytodetritus to the sea floor in turn impacting and limiting production of benthic foraminifera with the opposite effect prevailing during interglacial periods. Down-core variations in right-coiling Neogloboquadrina pachyderma abundance and the composition of planktonic foraminiferal faunas indicate the Subarctic Front did not shift southward over the study site during the past 37064000 years. Alternatively, variations in faunal composition indicate that Subtropical Water prevailed in the study area throughout this period. No clear faunal evidence of the presence of the ‘Kuroshio Extension’ was found in core NP36 reflecting the loss of heat and tropical faunal elements from this water mass as it flowed eastward during late Quaternary climatic maxima and minima. [13] Sun Xiangping.A comparison of characteristics between the subtropical countercurrent, the north equatorial current and the north equatorial countercurrent in the Northwestern Pacific Ocean[J]. Journal of Oceanography of Huanghai and Bohai Seas, 2000, 18(1): 1-12. [孙湘平. 西北太平洋副热带逆流、北赤道流、北赤道逆流几个特征的比较[J]. 黄渤海海洋学报, 2000, 18(1): 1-12.] 根据 1 37°E断面 1 967～ 1 995年冬、夏季的温、盐资料 ,计算和分析该断面的地转流 ;分析 1 44°E断面上投放卫星跟踪漂流浮标的漂移轨迹 ;结合 CSK图集中的海面重力势分布 ,对副热带逆流、北赤道流和北赤道逆流几个特征的相同点和不同点进行比较 ,得出若干有益的结论 :( 1 )副热带逆流、北赤道流、北赤道逆流 ,并不是单纯的单支海流 ,而是存在着两支或多支现象 ;( 2 )流速结构的带状分布 ,东、西向流相互交错间隔出现 ,流层较浅 ,均为表层流或近表层流 ;( 3)多年平均而言 ,3支海流的流速以北赤道逆流最强 ,北赤道流次之 ,副热带逆流最弱 ;流量则不同 ,北赤道流 [14] Nagashima K, Tada R, Matsui H, et al. Orbital- and millenial-scale variations in Asian dust transport path to the Japan Sea[J]. Palaeogeography Palaeoclimatology Palaeoecology, 2007, 247(1): 144-161. Orbital- and millennial-scale variations in the Asian monsoon and its probable association with the Dansgaard–Oeschger (D–O) Cycles have been demonstrated by previous studies. However, the origin and nature of such variations are poorly understood. The Japan Sea is located down wind of the arid areas of the Eurasian continent, and thus receives significant amounts of aeolian dust. Consequently, the hemipelagic sediments of the Japan Sea are expected to record a continuous aeolian dust accumulation, which may provide information about the past variations in Asian monsoon. Grain size, flux, and provenance of aeolian dust in the sediments were examined using two sediment cores obtained from the northern and southern parts of the Japan Sea in order to understand the spatial variability of Asian monsoon. Since the silt fraction of the detrital materials in hemipelagic sediments of the Japan Sea is composed predominantly of aeolian dust, the grain size, flux, and provenance of the silt fraction were examined. The Taklimakan Desert–Loess Plateau and Siberia–Northeast China areas were identified as possible source areas of aeolian dust in the sediments of the Japan Sea based on the Electron Spin Resonance (ESR) signal intensity and crystallinity of quartz. Moreover, the relative contribution of aeolian dust from each source area was estimated based on the ESR signal intensity and crystallinity of quartz. Aeolian dust fluxes from the two source areas at the southern site were then estimated. Grain size and flux of eolian dust at the northern site, and fluxes of aeolian dust from two source areas at the southern site show orbital-scale variations in harmony with the insolation change at 30° N in June. These results indicate orbital-scale changes in the extent of the arid area and/or frequency of dust storms in the Taklimakan Desert–Loess Plateau and Siberia–Northeast China areas, and suggest that southward (northward) shifts of the westerly jet axis occurred together with either intensified (weakened) winter monsoon, decreased (increased) winter precipitation in the Siberia–Northeast China area, or southeastward (northwestward) shifts of summer monsoon limit during periods of smaller (larger) insolation at 30° N in June. In addition to these orbital-scale variations, millennial-scale variations possibly associated with the D–O Cycles are observed in the grain size record of aeolian dust at the two sites. Based on analogy with orbital-scale variations, these millennial-scale variations are considered to reflect millennial-scale changes in the position of the westerly jet axis together with the changes either in winter monsoon intensity, winter precipitation, or position of summer monsoon limit. Our results suggest N–S oscillations in the westerly jet and summer monsoon limit, and changes in the intensity of the winter monsoon on orbital and millennial timescales. [15] Serno S, Winckler G, Anderson R F, et al. Change in dust seasonality as the primary driver for orbital-scale dust storm variability in East Asia[J]. Geophysical Research Letter, 2017, 44: 3 796-3 805. Glacial periods are recognized to be dustier than interglacials, but the conditions leading to greater dust mobilization are poorly defined. Here we present a new high-resolution dust record based on 230Th-normalized 4He flux from Ocean Drilling Program site 882 in the Subarctic North Pacific covering the last 170,000 years. By analogy with modern relationships, we infer the mechanisms controlling orbital-scale dust storm variability in East Asia. We propose that orbital-scale dust flux variability is the result of an expansion of the dust season into summer, in addition to more intense dust storms during spring and fall. The primary drivers influencing dust flux include summer insolation at subarctic latitudes and variable Siberian alpine glaciation, which together control the cold air reservoir in Siberia. Changes in the extent of the Northern Hemisphere ice sheets may be a secondary control. [16] Ma Jing, Xu Haiming.The relationship between meridional displacement of the oceanic front in Kuroshio extension during spring and atmospheric circulation in East Asia[J]. Journal of the Meteorological Sciences, 2012, 32(4): 375-384. [马静, 徐海明. 春季黑潮延伸体海洋锋区经向位移与东亚大气环流的关系[J]. 气象科学, 2012, 32(4): 375-384.] Index of the meridional displacement of the oceanic front in Kuroshio extension region during spring is defined based on high-resolution sea surface temperature dataset. We investigate its relations with the jet stream, storm track and later stage of rainfall in East Asia.Our analysis shows that there exist significantly interannual and interdecadal changes in north-south position of the oceanic front in Kuroshio extension during spring.A close relationship is found between north-south position of the oceanic front and the storm track in Pacific region, jet stream in East Asia. As the oceanic front is inclinable to the north in spring, storm track and jet stream shift northward in June accordingly, and vice versa. Further research also reveals that atmospheric circulation in East Asia can be influenced by the displacement of oceanic front,resulting in precipitation anomaly in June. In correspondence with the northerly (southerly) position of oceanic front, rain band migrates northward (southward) perceptibly. [17] Wu Boyu.Kuroshio current-Ⅲ kuroshio current plankton and others[J]. Marine Bulletin, 1986, (3): 78-82. [伍伯瑜. 黑潮流系-Ⅲ黑潮流系的浮游生物及其他[J]. 海洋通报, 1986, (3): 78-82.] 正 一、黑潮流系中的浮游生物 1.黑潮流系中的浮游植物 黑潮中的浮游植物的群集状况,具有因地而异,垂直分布不均的特点。从黑潮流系南部的菲律宾东面水域直到台湾东面附近,蓝藻中的束毛藻属数量较大,但在日本本州南面水域,蓝藻的数量就相对于叶绿素的数量而变动。 [18] Kuehn H, Lembkejene L, Gersonde R, et al. Laminated sediments in the Bering Sea reveal atmospheric teleconnections to Greenland climate on millennial to decadal timescales during the last deglaciation[J]. Climate of the Past Discussions, 2014, 10(3):2 215-2 236. During the last glacial termination, the upper North Pacific Ocean underwent dramatic and rapid changes in oxygenation that lead to the transient intensification of oxygen minimum zones (OMZs), recorded by the widespread occurrence of laminated sediments on circum-Pacific continental margins. We present a new laminated sediment record from the mid-depth (1100 m) northern Bering Sea margin that provides insight into these deglacial OMZ maxima with exceptional, decadal-scale detail. Combined ultrahigh-resolution micro-X-ray-fluorescence (micro-XRF) data and sediment facies analysis of laminae reveal an alternation between predominantly terrigenous and diatom-dominated opal sedimentation. The diatomaceous laminae are interpreted to represent spring/summer productivity events related to the retreating sea ice margin. We identified five laminated sections in the deglacial part of our site. Lamina counts were carried out on these sections and correlated with the B??lling???Aller??d and Preboreal phases in the North Greenland Ice Core (NGRIP) oxygen isotope record, indicating an annual deposition of individual lamina couplets (varves). The observed rapid decadal intensifications of anoxia, in particular within the B??lling???Aller??d, are tightly coupled to short-term warm events through increases in regional export production. This dependence of laminae formation on warmer temperatures is underlined by a correlation with published Bering Sea sea surface temperature records and ??18O data of planktic foraminifera from the Gulf of Alaska. The rapidity of the observed changes strongly implies a close atmospheric teleconnection between North Pacific and North Atlantic regions. We suggest that concomitant increases in export production and subsequent remineralization of organic matter in the Bering Sea, in combination with oxygen-poor waters entering the Being Sea, drove down oxygen concentrations to values below 0.1 mL L???1 and caused laminae preservation. Calculated benthic???planktic ventilation ages show no significant variations throughout the last deglaciation, indicating that changes in formation rates or differing sources of North Pacific mid-depth waters are not prime candidates for strengthening the OMZ at our site. The age models established by our correlation procedure allow for the determination of calendar age control points for the B??lling???Aller??d and the Preboreal that are independent of the initial radiocarbon-based chronology. Resulting surface reservoir ages range within 730???990 yr during the B??lling???Aller??d, 800???1100 yr in the Younger Dryas, and 765???775 yr for the Preboreal. [19] Tian Jun, Wang Pinxian, Cheng Xinrong.Stable isotope equilibrium test between benthic foraminifer Cibicidoides and Uvigerina at ODP Site 1143, Southern South China Sea[J]. Earth Science—Journal of China University of Geoscience, 2004, 29(1):1-6. [田军, 汪品先, 成鑫荣. 南海ODP1143站底栖有孔虫Cibicidoides与Uvigerina稳定氧碳同位素值的均衡实验[J]. 地球科学——中国地质大学学报, 2004, 29(1):1-6.] [20] Mortlock R A, Froelich P N.A simple method for the rapid determination of biogenic opal in pelagic marine sediments[J]. Deep Sea Research Part I: Oceanographic Research Papers, 1989, 36(9): 1 415-1 426. Biogenic opal in marine sediments is determined with a single extraction of silica into 2 M Na 2CO 3 solution at 85°C for 5 h. The method has been applied to sediments of varied opal contents (3–100% opal) and age (Recent to Pliocene). It is sufficiently simple, precise and rapid to be used routinely for high resolution spatial and temporal mapping of the biosiliceous component in deep-sea sediments. Evidence from timed dissolution experiments, germanium/silicon ratios, and comparisons with other methodologies demonstrates that systematic errors produced by leaching of silica from aluminosilicates or by incomplete dissolution of siliceous microfossils are small compared to the range of opal contents in biogenic sediments. When estimating mass accumulation rates, we report sedimentary biogenic opal both as %Si OPAL (silicon content) and as %OPAL (2.4 × %Si OPAL). This conversion accounts for the average water content of diatomaceous silica (about 10% water = SiO 2 · 0.4 H 2O). [21] Sun Yechen, Wang Rujian, Xiao Wenshen, et al. Biogenic and terrigenous coarse fractions in surface sediments of the western Arctic Ocean and their sedimentary environments[J]. Acta Oceanologica Sinica, 2011, 33(2): 103-114. [孙烨忱, 王汝建, 肖文申, 等. 西北冰洋表层沉积物中生源和陆源粗组分及其沉积环境[J]. 海洋学报, 2011, 33(2): 103-114.] 通过中国第1至第3次北极科学考察在北冰洋西部所采集的99个表层沉积物中生源与陆源粗组分的分析,研究了该海域表层生产力的变化,有机质来源以及陆源粗颗粒物质的输入方式和影响因素。研究区域生源组分所反映的表层生产力变化与通过白令海峡进入楚科奇海的3股太平洋洋流密切相关。楚科奇海西侧高盐高营养盐的阿纳德尔流流经区域,表层生产力普遍较高;东侧低盐低营养盐阿拉斯加沿岸流流经区域,浮游硅质生物生产力低,并且受陆源有机质输入影响显著。阿尔法脊和楚科奇海台较高的浮游钙质生物生产力与北大西洋水的注入密切相关。楚科奇海陆架区低的浮游钙质生物生产力与陆源物质的稀释作用和浮游钙质生物生活水深有关;加拿大海盆区低的浮游钙质生物生产力主要受到碳酸钙溶解作用的影响。研究区域表层沉积物中的陆源粗组分-冰筏碎屑(ice-rafted detritus,IRD)的分布主要受海冰和冰山的搬运,陆缘冰输入,河流输入以及太平洋入流水的影响。白令海峡入口处的陆源粗颗粒沉积主要受太平洋入流水影响;阿拉斯加近岸海域的陆源粗颗粒沉积来自于陆缘冰以及河流的输入;而北风脊高的IRD含量主要是由海冰和冰山所携带,被波弗特环流搬运至此,伴随着海冰和冰山的融化并卸载进入沉积物中。 [22] Zhang Haifeng, Wang Rujian, Sun Yechen, et al. Distribution pattern of biogenic components in surface sediments of the northern Bering Sea and their paleoceanographic implications[J]. Marine Geology & Quaternary Geology, 2011, 31(5): 79-87. [张海峰, 王汝建, 孙烨忱, 等. 白令海北部表层沉积物中的生源组分分布特征及其古海洋学意义[J]. 海洋地质与第四纪地质, 2011, 31(5): 79-87.] 对中国首次和第3次北极科学考察在白令海北部所采取的29个表层沉积物中的TOC、生源Opal和Ca-CO3含量等进行了研究,结果发现,TOC的高值出现在外陆架至中陆架区,其次为海盆区,白令海峡至内陆架最低;Opal的高值出现在海盆至陆坡边缘区,其次为外陆架至中陆架,白令海峡至内陆架最低;CaCO3的高值出现在内陆架至中陆架区,外陆架至海盆最低。外陆架至中陆架区高的TOC和Opal与该区现代上层水体中较高的叶绿素浓度和营养盐含量有关,反映了上层水体季节性的浮游植物勃发和高的初级生产力。内陆架至中陆架区域相对高的CaCO3可能与浮游植物颗石藻Emiliania huxleyi长期持续的勃发有关,而外陆架至海盆低的CaCO3可能与CaCO3溶解作用相关。外陆架和中陆架高的TOC和Opal可能来源于浮游生物的勃发和有机碳的输入。它们的Corg/N值介于6～9之间,说明其有机质主要来源于海洋自生的沉积,有机碳的输入可能受生物泵的控制。TOC和Opal的相关性分析显示了较高的相关系数（0.71）,反映有机碳与硅藻关系密切,硅藻等浮游植物的初级生产力可能控制着生物泵对碳的吸收和释放。 [23] Yang Shouye, Li Congxian.Compositions of organic elements and carbonate in the late Cenozoic sediments of the Changjiang Delta: Implication for paleoenvironmental changes[J]. Geochimica, 2006, 35(3):249-256. [杨守业, 李从先. 长江三角洲晚新生代沉积物有机碳、总氮和碳酸盐组成及古环境意义[J]. 地球化学, 2006, 35(3):249-256.] [24] Lisiecki L E, Raymo M E.A Pliocene-Pleistocene stack of 57 globally distributed benthic δ18O records[J]. Paleoceanography, 2005, 20(1). DOI: 10.1029/2004PA001071 [25] Woodard S C, Thomas D J, Hovan S, et al. Evidence for orbital forcing of dust accumulation during the early Paleogene greenhouse[J]. Geochemistry Geophysics Geosystems, 2013, 12(2): 364-371. The accumulation of wind blown (eolian) dust in deep-sea sediments reflects the aridity/humidity conditions of the continental region supplying the dust, as well as the 090008gustiness090009 of the climate system. Detailed studies of Pleistocene glacial-interglacial dust fluxes suggest changes in accumulation rates corresponding to orbital variations in solar insolation (Milankovitch cycles). While the orbital cycles found in sedimentary archives of the Pleistocene are intricately related to glacial growth and decay, similar global orbital signals recognized in deep-sea sediments of early Paleogene age, the last major greenhouse interval 0908046509000945 million years ago, could not have been linked to the waxing and waning of large ice sheets. Thus orbital signals recorded in early Paleogene sediments must reflect some other climate response to changes in solar insolation. To explore the potential connection between orbital forcing and the climate processes that control dust accumulation, we generated a high-resolution dust record for 09080458 Myr old sediments from Shatsky Rise (ODP Site 1209, paleolatitude 0908041500°N0900092000°N). The dust accumulation data provide the first evidence of a correlation between dust flux to the deep sea and orbital cyclicity during the early Paleogene, indicating dust supply responded to insolation forcing during the last major interval of greenhouse climate. Furthermore, the relative amplitude of the dust flux response during the early Paleogene greenhouse was comparable to that during icehouse climates. Thus, subtle variations in solar insolation driven by changes in Earth's orbit about the Sun may have had a similar impact on climate during intervals of overall warmth as they did during glacial-interglacial states. [26] Rea D K, Hovan S A.Grain size distribution and depositional processes of the mineral component of abyssal sediments: Lessons from the North Pacific[J]. Paleoceanography, 1995, 10(2): 251-258. Grain size analyses of the mineral component of abyssal Pacific surface sediments show two distinctly different size distributions that can be associated with sediments that are dominantly eolian and dominantly hemipelagic, respectively. In the range of 1 to 30 0008m, eolian grains show a distinct size mode at about 2 0008m (90207) and little material coarser than about 16 0008m (60207). Hemipelagic grains are characterized by a much flatter size distribution that has a broad size mode near 2 0008m (90207) and important amounts of material coarser than 16 0008m (60207). This ability to distinguish between hemipelagic and eolian grains will obviate some long-standing concerns in the interpretation of deep-sea sediments. Examples of the utility of this technique are given for the North Pacific and South Atlantic. [27] Raiswell R.Towards a global highly reactive iron cycle[J]. Journal of Geochemical Exploration, 2006, 88: 436-439. The global fluxes of iron oxy(hydr)oxides into the oceans from rivers, glaciers, atmospheric dust, hydrothermal activity, coastal erosion and diagenetic recycling have been quantified. The main sources to the shelf are from rivers, atmospheric dust and diagenetic recycling, and the main sources to the deep sea originate from glaciers or are exported from the shelf. [28] Deng Weibin, Hu Daquan, Tang Xingyan, et al.SPSS 19 (Chinese Edition) Statistical Analysis Practical Guide[M]. Beijing: Publishing House of Electronics Industry, 2012: 494-502. [邓维斌, 胡大权, 唐兴艳, 等. SPSS 19 (中文版) 统计分析实用教程[M]. 北京: 电子工业出版社, 2012: 494-502.] [29] Bonn W J, Gingele F X, Grobe H, et al. Paleoproductivity at the Antarctic continental margin: Opal and barium records of the last 400 kyr[J]. Palaeogeography Palaeoclimatology Palaeoecology, 1998, 139(3/4): 195-211. [30] Murray R W, Leinen M, Isern A R.Biogenic flux of Al to sediment in the central eqatorial Pacific Ocean: Evidence for increased productivity during glacial periods[J]. Paleoceanography, 1993, 8(5): 651-670. We examined the flux of Al to sediment accumulating beneath the zone of elevated productivity in the central equatorial Pacific Ocean, along a surface sediment transect at 13500°W as well as downcore for a 650 kyr record at 1.300°N, 133.600°W. Across the surface transect, a pronounced, broadly equatorially symmetric increase in Al accumulation is observed, relative to Ti, with Al/Ti ratios reaching values 30900094 times that of potential detrital sources. The profile parallels biogenic accumulation and the modeled flux of particulate 234Th, suggesting rapid and preferential adsorptive removal of Al from seawater by settling biogenic particles. Normative calculations confirm that most Al is unsupported by the terrigenous fraction. The observed distributions are consistent with previous observations of the relative and absolute behavior of Al and Ti in seawater, and we can construct a reasonable mass balance between the amount of seawater-sourced Al retained in the sediment and the amount of seawater Al available in the overlying column. The close tie between Al/Ti and biogenic accumulation (as opposed to concentration) emphasizes that biogenic sedimentary Al/Ti responds to removal-transport phenomena and not bulk sediment composition. Thus, in these sediments dominated by the biogenic component, the bulk Al/Ti ratio reflects biogenic particle flux, and by extension, productivity of the overlying seawater. The downcore profile of Al/Ti at 1.300°N displays marked increases during glacial episodes, similar to that observed across the surface transect, from a background value near Al/Ti of average upper crust. The excursions in Al/Ti are stratigraphically coincident with maxima in both bulk and CaCO3 accumulation and the excess Al appears to not be preferentially affiliated with opaline or organic phases. Consistent with the similar behavioral removal of Al and 234Th, the latter of which responds to the total particle flux, the Al flux reflects carbonate accumulation only because carbonate comprises the dominant flux in these particular deposits. These results collectively indicate that (1) Al in biogenic sediment and settling biogenic particles is strongly affected by a component adsorbed from seawater. Therefore, the common tenet that Al is dominantly associated with terrestrial particulate matter, and the subsequent use of Al distributions to calculate the abundance and flux of terrestrial material in settling particles and sediment, needs to be reevaluated. (2) The Al/Ti ratio in biogenic sediment can be used to trace the productivity of the overlying water, providing a powerful new paleochemical tool to investigate oceanic response to climatic variation. (3) The close correlation between the Al/Ti productivity signal and carbonate maxima downcore at 1.300°N suggests that the sedimentary carbonate maxima in the central equatorial Pacific Ocean record increased productivity during glacial episodes. [31] Murray R W, Knowlton C, Leinen M, et al. Export production and carbonate dissolution in the central equatorial Pacific Ocean over the past 1 Myr[J]. Paleoceanography, 2000, 15(6): 570-592. In order to quantify changes in export production and carbonate dissolution over the past 1 Myr in the central equatorial Pacific Ocean we analyzed Ba, P, Al Ti, and Ca in 1106 samples from five piston cores gathered from 500°S to 400°N at 14000°W. We focused on Ba/Ti, Al/Ti, and P/Ti ratios as export proxies and employed areally integrated time slice as well as time series strategies. Carbonate maxima from 0090009560 kyr are characterized by 1509000930% greater export than carbonate minima. The increases in export fall on glacial 020718O transitions rather than glacial maxima. From 560090009800 kyr, overlapping with the mid-Pleistocene transition, there is a very large increase in total export yet no glacial-interglacial variability. The highest latitudes (500°S and 400°N) record minimal absolute export change from glacials to interglacials and yet record the most extreme minima in percent CaCO3, indicating that carbonate records there are dominated by dissolution, whereas near the equator they are more influenced by changes in export. [32] Winckler G, Anderson R F, Schlosser P.Equatorial Pacific productivity and dust flux during the mid-Pleistocene climate transition[J]. Paleoceanography, 2005, 20(4): 347-356. [1] We present a helium isotope record for core TT013-114PC from the central equatorial Pacific (14000°W, 400°N, 4432 m water depth) spanning a period of 1 million years. We focus on the time interval from 560 to 800 kyr, largely coinciding with the mid-Pleistocene climate transition (MPT) when the dominant period of the Earth's climate variability shifted from 41 kyr to 100 kyr. The terrigenous 4He concentrations from our study correlate very well with published titanium concentrations in this core strongly supporting the use of terrigenous 4He as a monitor of continental dust. Normalizing titanium and terrigenous 4He concentrations to 3He suggests that the dust supply during the MPT was approximately 30% lower compared to the subsequent period (560090009100 kyr). The 3He-normalized barium, aluminum and phosphorus concentrations, trace elements with a predominantly biogenic source in these sediments, are relatively constant. This is in contrast to previous studies that reported an apparent rise of titanium-normalized productivity proxies. Rather than a significant increase in productivity during the MPT, we conclude that the dust flux to the central equatorial Pacific was reduced and that the export productivity was approximately constant during this period of climate reorganization. [33] Waelbroeck C, Pichat S, Evelyn Böhm, et al. Relative timing of precipitation and ocean circulation changes in the western equatorial Atlantic over the last 45 ky[J]. Climate of the Past Discussions, 2018,14:1 315-1 330. [34] Francesca Vallé, Westerhold T, Dupont L M.Orbital-driven environmental changes recorded at ODP Site 959 (eastern equatorial Atlantic) from the Late Miocene to the Early Pleistocene[J]. International Journal of Earth Sciences, 2017, 106(3):1 161-1 174. Palaeorecords from tropical environments are important to explore the linkages between precipitation, atmospheric circulation and orbital forcing. In this study, new high-resolution XRF data from ODP Site 959 (337'N, 244'W) have been used to investigate the relationship between palaeoenvironmental changes in West Africa and sedimentation in the tropical East Atlantic Ocean. Iron intensity data have been used to build a 91-m composite depth record that has been astronomically tuned allowing the development of a detailed age model from 6.2 to 1.8 Ma. Based on this new stratigraphy, we studied the variations of Ti/Al, Ti/Ca and Al/Si ratios, proxies for aeolian versus fluvial supply, as dust indicator and fine versus coarse grain size, respectively. We discuss sedimentation patterns at ODP Site 959 associated with the environmental changes from the late Miocene until the early Pleistocene. During the interval corresponding to the earlier stages of the Messinian Salinity Crisis, our proxy records indicate enhanced run-off from the West African continent and major supply of fine material at ODP Site 959, suggesting a stronger monsoon and increased precipitation during eccentricity minima. A long-term decrease of river supply is documented after 5.4 Ma until the end of the Pliocene. From the increased values and variability of Ti/Al and Ti/Ca ratios, we suggest that after 3.5 Ma dust started to reach the study site probably as a result of the southward shift of the Intertropical Convergence Zone during winter. Between 3.2 and 2.9 Ma, ODP Site 959 Ti/Ca ratios exhibit three maxima corresponding to eccentricity maxima similarly to other dust records of northern Africa. This suggests continent-wide aridity or larger climate variability during that interval. Eccentricity forcing (405 and 100 kyr) and precession frequencies are found in the entire studied interval. The variations of Ti/Al ratio suggest stronger seasonality between 5.8 and 5.5 Ma and after 3.2 Ma. [35] Wang Rujian, Jian Zhimin, Xiao Wenshen, et al. The correlations between the east Asian monsoon, the world Ice volume, orbital drive and Opal record in the South China Sea during Quaternary[J]. Science in China (Series D), 2007, 37(4): 521-533. [王汝建, 翦知湣, 肖文申, 等. 南海第四纪的生源蛋白石记录: 与东亚季风、全球冰量和轨道驱动的联系[J]. 中国科学:D辑, 2007, 37(4): 521-533.] 据南海中部1993～1996年颗粒通量的研究表明，蛋白石通量可以用来指示初级生产力的变化，这一结果为追溯南海第四纪冰期旋回中表层生产力的变化与东亚季风的演化关系提供了依据．通过南海ODP184航次等6个站位生源蛋白石含量及其堆积速率的研究发现，北部站位蛋白石含量及其堆积速率自470～900ka以来明显增加，并且冰期升高，间冰期降低；而南部站位自420～450ka以来明显增加，并且间冰期升高，冰期降低．这种晚第四纪冰期旋回中蛋白石含量及其堆积速率的变化反映了南、北部表层生产力呈现“跷跷板”式的变化，即冰期冬季风加强，北部表层生产力增加，南部表层生产力降低；间冰期夏季风加强，南部表层生产力增加，北部表层生产力：降低．北部ODP1144站和南部ODP1143站第四纪以来蛋白石含量与全球冰量（δ^18O）和轨道参数（ETP）的时间序列交叉频谱分析和以前的研究结果显示，东亚冬季风和夏季风的变化可能有不同的驱动机制．在轨道时间尺度上，全球冰量的变化可能是东亚冬季风强度和时间变化的主要控制因素，而岁差和斜率相关的北半球夏季太阳辐射量的变化可能是东亚夏季风强度和时间变北的主要控制因素． [36] Wang Rujian, Xiao Wenshen, Xiang Fei, et al. Distribution pattern of biogenic components in surface sediments of the weatern Arctic Ocean and their palaeoceanographic implications[J]. Marine Geology & Quaternary Geology, 2007, 27(6): 61-69. [王汝建, 肖文申, 向霏, 等. 北冰洋西部表层沉积物中生源组分及其古海洋学意义[J]. 海洋地质与第四纪地质, 2007, 27(6): 61-69.] 通过对中国首次和第二次北极科学考察在北冰洋西部所采取的66个表层沉积物中生源组分的分析,探讨了该海区表层生产力变化与水团的相互关系。楚科奇海西南部呈现出高的有机碳和生源蛋白石含量,而中部和东部哈罗德浅滩至阿拉斯加沿岸,以及楚科奇海台、北风脊和加拿大海盆表现出低的有机碳和生源蛋白石含量。楚科奇海陆架区表层沉积物以底栖有孔虫为主,丰度低;而楚科奇海台、北风脊和加拿大海盆则以浮游有孔虫占绝对优势,丰度较高。生源组分的分布特征显然与通过白令海峡进入楚科奇海的三股太平洋水和大西洋次表层水相关。楚科奇海西侧沿富营养的阿纳德尔流方向的区域呈现出高的表层生产力。而东侧受寡营养的阿拉斯加沿岸流及阿拉斯加西北沿岸陆源物质输入的影响,呈现出低的表层生产力。北纬75°以北及加拿大海盆受海冰覆盖影响,也表现出最低的表层生产力。而受北大西洋次表层水的影响,楚科奇海陆架外侧高纬海域表现出较高的钙质生物生产力。表层沉积物中Corg/N比值及其分布反映楚科奇海表层沉积物中的有机碳以海洋自身来源为主,且主要受生物泵过程控制。有机碳和生源蛋白石含量呈现高的正相关关系,说明硅藻等浮游植物的初级生产力可能控制着生物泵对碳的吸收和释放。 [37] Lam P J, Bishop J K B. The continental margin is a key source of iron to the HNLC North Pacific Ocean[J]. Geophysical Research Letters, 2008, 35(7): 521-539. The Continental Margin is a Key Source of Iron to the HNLC North Pacific Ocean Phoebe J. Lam 1,2 and James K.B. Bishop 2,3 Dept. of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, MA 02540 Earth Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 Dept. of Earth and Planetary Science, University of California, Berkeley, Berkeley, CA 94720 Abstract Here we show that labile particulate iron and manganese concentrations in the upper 500m of the Western Subarctic Pacific, an iron-limited High Nutrient Low Chlorophyll (HNLC) region, have prominent subsurface maxima between 100-200 m, reaching 3 nM and 600 pM, respectively. The subsurface concentration maxima in particulate Fe are characterized by a more reduced oxidation state, suggesting a source from primary volcagenic minerals such as from the Kuril/Kamchatka margin. The systematics of these profiles suggest a consistently strong lateral advection of labile Mn and Fe from redox-mobilized labile sources at the continental shelf supplemented by a more variable source of Fe from the upper continental slope. This subsurface supply of iron from the continental margin is shallow enough to be accessible to the surface through winter upwelling and vertical mixing, and is likely a key source of bioavailable Fe to the HNLC North Pacific. Keywords: iron, continental margin, HNLC [38] Bordiga M, Cobianchi M, Lupi C, et al. Coccolithophore carbonate during the last 450 ka in the NW Pacific Ocean (ODP site 1209B, Shatsky Rise)[J]. Journal of Quaternary Science, 2014, 29(1): 57-69. This study focuses on Pleistocene–Holocene sediments from the Shatsky Rise (Ocean Drilling Program Site 1209B, NW Pacific Ocean). We quantify the contribution of calcite made by coccoliths in oceanic sediments, investigating the role of calcareous nannoplankton during the last 450 ka. Coccolith carbonate constitutes 60–90% of bulk carbonate. Coccolith carbonate accumulation rates (CARs) and CaCO3 fine fraction confirm that coccolithophores are major contributors to the carbonate export and accumulation. Primary productivity shows highest values from marine isotope stage (MIS) 12 to 8. Thereafter, although coccolith calcite content remains high, other sediment components, such as as foraminifera and biogenic opal, seem to be favored, perhaps related to an increase in fertilization by eolian dust. Our results demonstrate the important role of coccolithophore production and sedimentation on the regulation of ocean carbonate chemistry on time scales >1000–100 000 years. On glacial–interglacial scales, coccolithophore productivity could have affected deep-water saturation by buffering deep-sea CO2 through increased carbonate dissolution episodes. Spectral and wavelet analyses are consistent with CARs primarily driven by glacial–interglacial variability and obliquity-controlled changes. Coccolith-based paleoceanographic reconstructions allow us to establish that during the last 450 ka the mid-latitudes of the NW Pacific are controlled by the dynamics of the El Ni09o Southern Oscillation perturbations and Boreal Monsoon system. [39] Martin J H, Coale K H, Johnson K S, et al. Testing the iron hypothesis in ecosystems of the equatorial Pacific Ocean[J]. Nature, 1994, 371(6 493): 123-129. The idea that iron might limit phytoplankton growth in large regions of the ocean has been tested by enriching an area of 64 km 2 in the open equatorial Pacific Ocean with iron. This resulted in a doubling of plant biomass, a threefold increase in chlorophyll and a fourfold increase in plant production. Similar increases were found in a chlorophyll-rich plume down-stream of the Galapagos Islands, which was naturally enriched in iron. These findings indicate that iron limitation can control rates of phytoplankton productivity and biomass in the ocean. [40] Zhang Jiangyong, Wang Pinxian, Li Qianyu, et al. Western equatorial Pacific productivity and carbonate dissolution over the last 550 kyr: Foraminiferal and nannofossil evidence from ODP Hole 807A[J]. Marine Micropaleontology, 2007, 64(3/4): 121-140. We analyzed foraminiferal and nannofossil assemblages and stable isotopes in samples from ODP Hole 807A on the Ontong Java Plateau in order to evaluate productivity and carbonate dissolution cycles over the last 550 kyr (kilo year) in the western equatorial Pacific. Our results indicate that productivity was generally higher in glacials than during interglacials, and gradually increased since MIS 13. Carbonate dissolution was weak in deglacial intervals, but often reached a maximum during interglacial to glacial transitions. Carbonate cycles in the western equatorial Pacific were mainly influenced by changes of deep-water properties rather than by local primary productivity. Fluctuations of the estimated thermocline depth were not related to glacial to interglacial alternations, but changed distinctly at 280 kyr. Before that time the thermocline was relatively shallow and its depth fluctuated at a comparatively high amplitude and low frequency. After 280 kyr, the thermocline was deeper, and its fluctuations were at lower amplitude and higher frequency. These different patterns in productivity and thermocline variability suggest that thermocline dynamics probably were not a controlling factor of biological productivity in the western equatorial Pacific Ocean. In this region, upwelling, the influx of cool, nutrient-rich waters from the eastern equatorial Pacific or of fresh waters from rivers have probably never been important, and their influence on productivity has been negligible over the studied period. Variations in the inferred productivity in general are well correlated with fluctuations in the eolian flux as recorded in the northwestern Pacific, a proxy for the late Quaternary history of the central East Asian dust flux into the Pacific. Therefore, we suggest that the dust flux from the central East Asian continent may have been an important driver of productivity in the western Pacific. [41] Kennedy P, Kennedy H, Papadimitriou S.The effect of acidification on the determination of organic carbon, total nitrogen and their stable isotopic composition in algae and marine sediment[J]. Rapid Communications in Mass Spectrometry, 2005, 19(8): 1 063-1 068. Abstract We investigated the effects of sample acidification on the stable carbon and nitrogen isotopic composition (delta13C and delta15N), as well as the organic carbon (OC) and total nitrogen (TN) composition, of an algal culture and a marine sediment. Replicate measurements of untreated and acid-treated samples were made using 1 M, 2 M and 6 M HCl, 6% H2SO3 and 1 M H3PO4. For all treatments the precision of the analysis for the acid-treated sample was equal to or less than that in the non-acidified sample. For the algae, analysis of variance (ANOVA) indicated no significant differences in the mean OC and TN concentration, or delta13C and delta15N composition, between any acid treatment and non-acidified samples. For the sediment sample a comparison could only be made between the different acid treatments because the untreated contained significant amounts ( approximately 30%) of carbonate carbon. ANOVA indicated that the mean OC determined in sediment samples after the 1 M HCl treatment and the mean delta13C values after the 6% H2SO3 and 1 M H3PO4 treatments were significantly different (p < 0.013 and < .05, respectively) from all other treatments. Mass balance calculations indicate that in some instances delta13C values were biased due to a contribution from unreacted carbonate carbon. There were no significant differences in the mean TN between any acid-treated and non-acidified samples. The mean delta15N values after 6 M HCl, 6% H2SO3 and 1 M H3PO4 treatments were significantly different from the untreated sediment sample (p < 0.044). Based on the significant bias observed for the delta15N and delta13C values, a weak (1-2 M) HCl solution is confirmed as the most appropriate acid for the removal of inorganic carbon from natural materials requiring elemental and isotopic analysis. Copyright 2005 John Wiley & Sons, Ltd. [42] Zhang Haifeng, Wang Rujian, Sun Yechen, et al. Distribution pattern of biogenic components in surface sediments of northern Bering Sea and their palaeoceanographic implications[J]. Marine Geology & Quaternary Geology, 2011, 31(5): 79-87. [张海峰, 王汝建, 孙烨忱, 等. 白令海北部表层沉积物中的生源组分分布特征及其古海洋学意义[J]. 海洋地质与第四纪地质, 2011, 31(5): 79-87.] 对中国首次和第3次北极科学考察在白令海北部所采取的29个表层沉积物中的TOC、生源Opal和Ca-CO3含量等进行了研究,结果发现,TOC的高值出现在外陆架至中陆架区,其次为海盆区,白令海峡至内陆架最低;Opal的高值出现在海盆至陆坡边缘区,其次为外陆架至中陆架,白令海峡至内陆架最低;CaCO3的高值出现在内陆架至中陆架区,外陆架至海盆最低。外陆架至中陆架区高的TOC和Opal与该区现代上层水体中较高的叶绿素浓度和营养盐含量有关,反映了上层水体季节性的浮游植物勃发和高的初级生产力。内陆架至中陆架区域相对高的CaCO3可能与浮游植物颗石藻Emiliania huxleyi长期持续的勃发有关,而外陆架至海盆低的CaCO3可能与CaCO3溶解作用相关。外陆架和中陆架高的TOC和Opal可能来源于浮游生物的勃发和有机碳的输入。它们的Corg/N值介于6～9之间,说明其有机质主要来源于海洋自生的沉积,有机碳的输入可能受生物泵的控制。TOC和Opal的相关性分析显示了较高的相关系数（0.71）,反映有机碳与硅藻关系密切,硅藻等浮游植物的初级生产力可能控制着生物泵对碳的吸收和释放。 [43] Thunell R C, Miao Q, Calvert S E, et al. Glacial-holocene biogenic sedimentation patterns in the South China Sea: Productivity variations and surface water pCO2[J]. Paleoceanography, 1992, 7(2): 143-162. A bathymetric transect of cores in the South China Sea extending from 4200-m to less than 1000-m water depth has been examined for glacial-interglacial changes in carbonate and organic carbon sedimentation. Typical 090008Pacific carbonate cycles090009 (high carbonate content during glacials and low carbonate content during interglacials) characterize cores from water depths deeper than 3500 m. In contrast, 090008Atlantic carbonate cycles090009 (low carbonate during glacials and high carbonate during interglacials) are observed in cores from depths shallower than 3000 m as a result of increased dilution of carbonate by terrigenous material during glacial low stands of sea level. Glacial-interglacial changes in the carbonate chemistry of South China Sea intermediate and deep waters resulted in significant changes in the positions of the carbonate compensation depth (CCD) and the aragonite compensation depth (ACD). During the last glacial the CCD and ACD were at least 400 and 1200 m deeper, respectively, than at present. Organic carbon accumulation rates in the South China Sea were approximately 2 times higher during the last glacial than the Holocene. Carbon isotopic analyses and C/N ratios of the organic matter indicate that only a small fraction of the increase in glacial organic carbon accumulation can be attributed to input of terrestrial carbon. On the basis of this we conclude that surface water productivity in the South China Sea was approximately 2 times higher during the last glacial maximum. This is consistent with previous studies which have demonstrated that glacial productivity was higher in low- to mid-latitude regions of the Atlantic and eastern Pacific. The deglacial decrease in organic carbon accumulation is accompanied by a decrease in 020713Corg. Using the relationship between 020713Corg and [CO2](aq) developed by Popp et al. [1989], we estimate that surface water pCO2 values in the South China Sea during the last 25,000 years were very similar to atmospheric CO2 concentrations. [44] Hedges J I, Clark W A, Quay P D, et al. Compositions and fluxes of particulate organic material in the Amazon River[J]. Limnology & Oceanography, 1986, 31(4): 717-738. Lignin, elemental, and stable carbon isotope compositions are reported for local plants and for coarse $(> 63 \mu m)$ and fine $(< 63 \mu m)$ suspended particulate materials collected along a 1,950-km reach of the lower Amazon River during four contrasting stages of the 1982-1983 hydrograph. Fluxes of chemically recognizable lignin in the two size classes generally parallel each other along the mainstem with the fine fraction usually predominating. Particulate organic matter transported in the coarse size fraction of the mainstem and its major tributaries is composed of recently formed and well preserved tree leaf debris along with some wood. Organic matter in the fine size fraction is comparatively old, degraded, and rich in immobilized nitrogen and derives primarily from soils. C-4 grasses, which are abundant in the mainstem floodplain (varzea), are not major components of either the coarse or fine particulate material in the river. Particulate organic matter in both size fractions is introduced largely from upstream sources within the Rio Solimoes and Rio Madeira drainage basins. Most of this organic matter is unreactive and is transported conservatively with mineral particles along the Amazon mainstem. However, some downstream compositional trends are seen in both size fractions which reflect the addition or exchange of highly degraded, 13C-depleted, and lignin-poor organic materials from lower basin sources. [45] Ruth U, Bigler M, Röthlisberger R, et al. Ice core evidence for a very tight link between North Atlantic and east Asian glacial climate[J]. Geophysical Research Letters, 2007, 34(3): 116-142. Corresponding millennial-scale climate changes have been reported from the North Atlantic region and from East Asia for the last glacial period on independent timescales only. To assess their degree of synchrony we suggest to interpret Greenland ice core dust parameters as proxies for the East Asian monsoon systems. This allows comparing North Atlantic and East Asian climate on the same timescale in high resolution ice core data without relative dating uncertainties. We find that during Dansgaard-Oeschger events North Atlantic region temperature and East Asian storminess were tightly coupled and changed synchronously within 5-10 years with no systematic lead or lag, thus providing instantaneous climatic feedback. The tight link between North-Atlantic and East Asian glacial climate could have amplified changes in the northern polar cell to larger scales. We further find evidence for an early onset of a Younger Dryas-like event in continental Asia, which gives evidence for heterogeneous climate change within East Asia during the last deglaciation. [46] Xiao Jule, Porter S C, An Zhisheng, et al. Grain size of quartz as an indicator of winter monsoon strength on the Loess Plateau of Central China during the last 130,000 yr[J]. Quaternary Research, 1995, 43(1): 22-29. The Chinese loess-paleosol sequence constitutes an important record of variations in Asian monsoon climate over the past 2.4 myr. Magnetic susceptibility of loess and paleosols has been used as a proxy for summer monsoon intensity, while median grain size has been regarded as a measure of the strength of winter monsoon winds that were responsible for most of the dust transport. However, median grain size is only an approximate index of winter monsoon strength because both paleosols and loess have been modified, to various degrees, by weathering processes that have produced pedogenic clay. The quartz component of loess and paleosols is largely unaffected by weathering processes and therefore constitutes a more reliable proxy index of monsoon wind strength. Median grain size (Qmd) and maximum grain size (Qmax) values of monomineralic quartz isolated from the loess-paleosol section at Luochuan in the central Loess Plateau are characterized by two main intervals during the last ca. 130,000 yr when these parameters were significantly greater than 9 and 85 m, respectively, and three main intervals when they were lower. The data imply that the winter monsoon weakened during the intervals with low Qmd and Qmax values, which coincide with marine oxygen isotope stages 5, 3, and 1, and was strongest ca. 67,000 and 20,000 yr ago during isotope stages 4 and 2. However, both quartz grainsize records display second-order high-frequency, high-amplitude variations, which are lacking in the magnetic susceptibility record, that imply rapid and significant changes in atmospheric conditions that affect dust transport and deposition. [47] Serno S, Winckler G, Anderson R F, et al. Eolian dust input to the Subarctic North Pacific[J]. Earth & Planetary Science Letters, 2014, 387(1): 252-263. 61Spatial survey of dust tracers 4Heterr, 232Th and REE in the Subarctic North Pacific.61Sedimentary lithogenic components are deconvolved with dust and volcanic endmembers.61High dust fluxes in the southwest SNP and constant lower fluxes elsewhere are found.61Sedimentary and dissolved Th-based dust fluxes from seawater show good consistency.61A constant eolian dust grain size mode at 4 μm over the entire SNP is observed. [48] Sun Donghuai, Su Ruixia, Bloemendal J, et al. Grain-size and accumulation rate records from Late Cenozoic aeolian sequences in northern China: Implications for variations in the East Asian winter monsoon and westerly atmospheric circulation[J]. Palaeogeography Palaeoclimatology Palaeoecology, 2008, 264(1/2): 39-53. We attempt to reconstruct the history of westerly and monsoonal circulations in northern China using variations in sediment grain-size and accumulation rate at four loess sections in the central Chinese Loess Plateau. The initiation of aeolian accumulation at about 7.602Ma in the main part of the Chinese Loess Plateau probably marked the onset of the monsoonal circulation. Both the monsoonal and westerly circulations weakened from 7.6 to 5.202Ma. Subsequently, the monsoonal circulation strengthened progressively from 5.202Ma to the present; in addition the westerly circulation strengthened from 5.2 to 0.602Ma, but then weakened thereafter and especially during the last 0.602Ma. Comparison of our aeolian records and the deep sea sediment record suggests that the strengthening trends of the monsoonal and westerly circulations were associated with the progressive development of global ice sheets during the Late Cenozoic. Abrupt changes of both the monsoon and westerly circulations occurred at 7.6, 3.4 and 1.2–0.902Ma, together with a weakening trend of the westerly circulation in the last 0.602Ma, and are interpreted as the consequence of the episodic uplift of the Tibetan Plateau. Spatial differences in the grain-size characteristics amongst the four sections suggest that the circulation intensity and variability decreased from west to east across the Loess Plateau due to the topographic effect of the Tibetan Plateau. In addition, some spatial differences may have been the result of local topographic effects. [49] Sun Donghuai, An Zhisheng, Su Ruixia, et al. Dust deposition records of the recent 2.6 Ma monsoon circulation and westerly circulation in northern China[J]. Science in China (Series D), 2003, 33(6): 497-504. [孙东怀, 安芷生, 苏瑞侠, 等. 最近2.6 Ma中国北方季风环流与西风环流演变的风尘沉积记录[J]. 中国科学: D辑, 2003, 33(6): 497-504.] [50] Zhang Yaocun, Kuang Xueyuan, Guo Weidong, et al. Seasonal evolution of the upper-tropospheric westerly jet core over East Asia[J]. Geophysical Research Letters, 2006, 33(11): 317-324. The location change of the westerly jet core at upper troposphere in June and July is investigated by using the NCEP/NCAR reanalysis data. The results show that the location of the westerly jet core changes rapidly from 140E to 90E during 35th 39th pentads, which corresponds to the plum rain period over East Asia. The location change of the jet core is actually the relative intensity change of the different westerly jet centers. The meridional temperature contrast in the troposphere is associated with the rapid location change of the jet core. The diabatic heating changes are the primary factor determining the seasonal evolution of the westerly jet core over East Asia. [51] Sun Jimin.Provenance of loess material and formation of loess deposits on the Chinese Loess Plateau[J]. Earth & Planetary Science Letters, 2002, 203(3/4): 845-859. Results of a multiple, isotopic, chemical and mineralogical analysis of loess from the three northwestern inland basins (the Junggar Basin, the Tarim Basin and the Qaidam Basin) and the Loess Plateau region of China are summarized. They suggest a qualification of the conventional views that the three northwestern basins were the important source areas of the Loess Plateau and that the sand deserts were the primary single source of the Chinese loess. It is argued that the gobi (stony desert) in southern Mongolia and the adjoining gobi and sand deserts (the Badain Jaran Desert, Tengger Desert, Ulan Buh Desert, Hobq Desert and Mu Us Desert) in China, rather than the three inland basins, are the dominant source areas of the Loess Plateau. However, although these gobi and sand deserts are regarded as the main source regions, they serve as dust and silt holding areas rather than dominant producers. The mountain processes (including glacial grinding, frost weathering, salt weathering, tectonic processes, and some fluvial comminution) in the Gobi Altay Mts., Hangayn Mts. and the Qilian Mts. have played an important role in producing the vast amounts of loess-sized material for forming the Loess Plateau. [52] Mingram J, Schettler G, Nowaczyk N, et al. The Huguang Maar Lake—A high-resolution record of palaeoenvironmental and palaeoclimatic changes over the last 78,000 years from South China[J]. Quaternary International, 2004, 122(1):85-107. A series of seven piston cores from the Huguang maar lake situated near the South China Sea coastline provides insight into regional palaeoenvironmental and palaeoclimatic changes in southern China over the last 78,000 years. The data set comprises a high-resolution record of magnetic susceptibility, dry density and water content, total organic carbon and inorganic carbon, total nitrogen, biogenic silica (BSiO 2), and palynological results. The time scale was developed by AMS 14C dating of 17 terrestrial plant macro-fossils. During the Last Glacial the Huguang record is characterised by an alternation of more temperate and humid periods (from 78 to 58 and 48 to 40.5 ka BP) and periods with predominance of grassland vegetation and possibly lowered lake level (from 58 to 48 and ca 40.5 to 15 ka BP). The Huguang data have been compared to regional marine and terrestrial records in order to discuss variability of the South-East Asian monsoon system. For most of the Last Glacial period the Huguang proxies do not exhibit marked millennial-scale variability as known from some long SE Asian and many North Atlantic records. This picture changes at about 15 cal ka BP when the Huguang and Greenland records appear to correlate well. A short climatic reversal which is assumed to reflect a Younger Dryas-type event is well recorded in the Huguang record. During the Holocene the Huguang multi-proxy data show a much higher variability than during the Last Glacial stage probably reflecting, at least for the early mid-Holocene, fluctuations in monsoon activity. However, the last 4000 years of the sediment record are clearly influenced by enhanced human activity and thus difficult to interpret in terms of palaeoclimate change. [53] Qu Wenjun, Zhang Xiaoye, Wang Dan, et al. The important significance of westerly wind study[J]. Marine Geology & Quaternary Geology, 2004, 24(1):125-132. [屈文军, 张小曳, 王丹, 等. 西风带研究的重要意义[J]. 海洋地质与第四纪地质, 2004, 24(1):125-132.] 西风带作为北大西洋气候区和东亚季风气候区之间的联系纽带，对东亚季风气候和西风带气候具有重要影响，西风带在一定意义上控制着东亚季风的北界。西风环流与青藏高原相互作用，对亚洲季风区气候乃至全球气候都有极其深刻的影响。西风环流在冰期-间冰期旋回中的位置、强度的剧烈变化对东亚季风气候和全球气候影响显著，对季风降水、西风带降水时空分布及亚洲粉尘活动和黄土形成、堆积等都有非常重要的意义。

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