赤道东北太平洋表层沉积物间隙水中营养盐的剖面分布及其海底扩散通量  

Pore water distribution and quantification of diffusive benthic fluxes of sil icate, nitrate and phosphate in surface sediments of the equatorial northeastern Pacific

作　　者：倪建宇[1] Michael Maggiulli 刘小涯[3] 王方国[3] 周怀阳[4] 

机构地区：[1]国家海洋局海底科学重点实验室,国家海洋局第二海洋研究所 [2]Institute of Environmental Technology, Technical University of Berlin,Berlin D-10623,Germany [3]国家海洋局第二海洋研究所区域海洋学重点实验室 [4]中国科学院广州地球化学研究所

出　　处：《地球化学》2005年第6期587-594,共8页Geochimica

基　　金：国家重点基础研究发展计划项目(G200078500);国家自然科学青年基金项目(40206012);大洋矿产资源勘探开发专项基金项目(Dy105-02-01)~~

摘　　要：对赤道东北太平洋海域表层沉积物间隙水中硅酸盐、磷酸盐和硝酸盐等营养盐的剖面分布三个航次的研究表明,研究区在采样深度内沉积物中有机质的分解以硝化作用为主。在水-沉积物界面附近硅酸盐、磷酸盐和硝酸盐都存在着极陡的浓度梯度,Fick扩散定理的计算结果表明,研究区内硅酸盐、磷酸盐和硝酸盐的海底扩散通量分别为-886.45～42.62μmol/(m2·d)、-3.04～5.83μmol/(m2·d)和-189.43～21.05μmol/(m2·d),且硅酸盐和硝酸盐主要是从沉积物向底层水体扩散,是底层水体营养盐的来源之一;研究区内硅酸盐、磷酸盐和硝酸盐的海底扩散通量存在着一定的时间和空间变化,这可能与因全球气候变化而导致的沉积环境的改变有关。Benthic fluxes and pore water compositions of silicate, nitrate and phosphate were investigated for surface sediments of the abyssal equatorial northeastern Pacific during three cruises （1999-2003）. The profile distributions of silicate, phosphate and nitrate suggest that the organic material decomposition in area is mainly through nitrification during early diagenesis. Based on benthic fluxes of nutrients calculated using Fick＇s first law, benthic fluxes of silicate, phosphate and nitrate are -886. 45- 42.62μmol/（m^2·d）, -3.04-5.83μmol/ （m^2·d） and -189.43-21.05 μmol/（m^2·d）, respectively, and perhaps silicate and nitrate are one of the major sources of nutrients for bottom water. Our results also reveal temporal and spatial variations of benthic fluxes for silicate, phosphate and nitrate, which may be related to sedimentation environment changes caused by global climatologic change.

关 键 词：营养盐 海底表层沉积物 间隙水 海底扩散通量 赤道东北太平洋 

分 类 号：P734.4[天文地球—海洋化学] P736.4[天文地球—海洋科学]