西北冰洋表层沉积物中的底栖有孔虫组合及其古环境意义  

Benthic foraminiferal assemblages in the western Arctic surface sediments and their paleoenrivonmental implications

作　　者：司贺园[1,2] 王汝建[3] 丁旋[1] 陈建芳[4] 汪卫国[5] 陈荣华[4] 程振波[6] 陈志华[6] 高爱国[7] 黄元辉[6] 李洪亮[4] 

机构地区：[1]中国地质大学海洋学院,北京100083 [2]海洋出版社,北京100081 [3]同济大学海洋地质国家重点实验室,上海200092 [4]国家海洋局第二海洋研究所,浙江杭州310012 [5]国家海洋局第三海洋研究所,福建厦门361005 [6]国家海洋局第一海洋研究所,山东青岛266061 [7]厦门大学海洋系,福建厦门361005

出　　处：《海洋学报》2013年第6期96-112,共17页

基　　金：国家自然科学基金重点项目(41030859);南北极环境综合考察与评估专项--2012年度北极海域海洋地质考察(CHINARE2012-03-02);中国地质调查局项目(水[2012]01-011-05)

摘　　要：通过对中国第1～4次北极考察在西北冰洋采集的表层沉积物中底栖有孔虫丰度及其优势种分布特征与环境因素关系的综合研究发现，楚科奇海区低的底栖有孔虫丰度主要受较高的陆源物质输入的稀释作用影响；楚科奇海台和阿尔法脊较高的底栖有孔虫丰度主要受到暖而成的大西洋中层水的影响；受碳酸钙溶解作用影响的门捷列夫深海平原和加拿大海盆底栖有孔虫丰度较低，并且水深3597m的站位出现了似瓷质壳的Pyrgowilliamsoni和Quinqueloculinaorien—talis，说明该区的CCD深度大于3600m。根据底栖有孔虫7个优势属种的百分含量分布特征可以划分出5个区域组合：南楚科奇海陆架一白令海峡组合以优势种Elphidiumexcavatum和Buccellafrigida为特征，可能反映受白令海陆架水影响的浅水环境；阿拉斯加沿岸一波弗特海组合以优势种Florilusscaphus和Elphidiumalbiumbilicatum为特征，可能反映受季节性海冰融化，低盐的阿拉斯加沿岸流以及河流淡水输入的低盐环境；大西洋中层水组合以优势种CassiduZinalaevigata为特征，可能反映高温高盐的大西洋中层水影响的环境；北极深层水组合以优势种Cibicideswuellerstorfi为特征，可能反映水深大于1500in低温高盐的北极深层水环境；门捷列夫深海平原组合以优势种Oridorsalisumbonatus为特征，可能反映低营养的底层水环境。Benthic foraminiferal assemblages in 139 western Arctic surface sediment samples recovered during the CHINARE IN IV cruises were studied. The relative abundances of each species were calculated and according to the spatial distribution pattern of dominant species, benthic foraminiferal assemblages were divided to determine the re lationship between the assemblage and environmental parameters. Our results show that the spatial distribution pat tern of low benthic foraminiferal abundance in the Chukchi shelf area is controlled by high terrigenous matter in put. In Chukchi Plateau and Alpha ridge, high benthic foraminiferal abundance is influenced by the warm and saline intermediate Atlantic water. In the Mendeleev Abyssal Plain and Canadian Basin, low benthic foraminiferal abun dance is influenced by calcium carbonate dissolution and the appearance of porcelainlike species Pyrgo iamsoni and Quinqueloculina orientalis at 3 597 m sites indicates the carbonate compensate depth （CCD） is greater than 3 600 m. Five assemblages related to spatial environmental factors can be determined by 7 dominant species. Southern Chukchi shelfBering Strait assemblage is dominantly characterized by Elphidiurn excavaturn and Buccel la frigida, representing the influence of shallow Bering Sea Shelf Water Alaska CoastBeaufort Sea assemblage is dominantly characterized by Florilus scaphusElphidium albiumbilicatum, indicating the low salinity environment due to seasonal sea ice melting and/or Alaska Coastal Current or riverine input Atlantic Intermediate Water as semblage is dominated by Cassidulina laevigata, representing warm saline Atlantic Intermediate Water Arctic Deep Water assemblage is dominated by Cibicides wuellerstorfi, reflecting the low temperature and high salinity environment greater than 1 500 m Mendeleev Abyssal Plain assemblage is dominated by Oridorsalis urnbonatus, showing the oligotrophic bottom water environment.

关 键 词：底栖有孔虫 空间分布模式 古环境 表层沉积物 西北冰洋 

分 类 号：Q958.8[生物学—动物学]