夏季珠江口及近岸海域悬浮颗粒物生物硅分析  

Determination of suspended biogenic silica in the Pearl River Estuaryand its adjacent coastal waters in summer

作　　者：俞小勇 徐杰[1,2] 龙爱民 钟宛宣[1,2] YU Xiao-yong;XU Jie;LONG Ai-min;ZHONG Wan-xuan(State Key laboratory of Tropical OceanograpAy ,South China Sea Institute of Oceanography,Chinese Academy of Sciences ,Guangzhou510301,China;University of Chinese Academy of Sciences ,Beijing100049,China)

机构地区：[1]热带海洋环境国家重点实验室,南海海洋研究所,中国科学院,广东广州510301 [2]中国科学院大学,北京100049

出　　处：《海洋学研究》2018年第3期67-75,共9页Journal of Marine Sciences

基　　金：国家自然科学基金项目资助(41476137).

摘　　要：2017年6月在珠江口及近岸海域61个站位采集了悬浮颗粒物生物硅(BSi,biogenic silica)和叶绿素a(Chl a)。利用RAGUENEAU et al(2005)提出的碱提取法测定了悬浮颗粒物生物硅,探讨不同环境条件下BSi浓度以及碱性提取液中岩源硅(LSi,lithogenic silica)的干扰程度。结果显示,Chl a质量浓度范围为0.06～8.64μg·L^(-1),悬浮颗粒物BSi浓度从低于检测限到14.3μmol·L^(-1),LSi浓度范围为0.00～9.56μmol·L^(-1);LSi/(LSi+BSi)比均值为0.38mol·mol^(-1)。提取液中测得的Si/Al比均值为2.42mol·mol^(-1),与RAGUENEAU et al(2005)报道值接近。研究区域内的表层BSi反映了硅藻的生物量,与Chl a存在显著线性相关。LSi对BSi测量的干扰程度存在明显的空间差异,总体上近岸BSi和LSi高,LSi/(LSi+BSi)比低;外海BSi和LSi低,LSi/(LSi+BSi)比高;河口内BSi低,LSi高,LSi/(LSi+BSi)比高;上升流区BSi和LSi高,LSi/(LSi+BSi)比高;底层较表层具有更高的LSi和LSi/(LSi+BSi)比。最后,对常用的几种碱提取法在应用时存在的问题作了探讨。Particulate biogenic silica (BSi)and chlorophyll a (Chl a)were determined at 61stations in the Pearl River Estuary and adjacent coastal waters in summer,in order to evaluate spatial variability in biogenic silica and the interference of lithogenic silica (LSi)in the bulk silica leached from the alkaline solution.Our results showed that ChI a concentrations ranged from 0.06to 8.64/μg .L^-1.Particulate BSi concentrations varied from the detect limit to 14.3μmol.L^-1,LSi concentrations were 0.00-9.56/μmol.L^-1and the average ratio of LSi to LSi+BSi was 0.38mol.mol^-1.The average ratio of Si to A1 was 2.42mol .mol^-1, comparable to the value reported by RAGUENEAU et a1(2005).A significant correlation was found between particulate biogenic silica and Chi a,which indicated diatom and phytoplankton biomass in the water column. LSi concentrations varied spatially,with high BSi,LSi and low LSi/(LSi+BSi)ratios in the nearshore area, low BSi,LSi and high LSi/(LSi+BSi)ratios in the offshore waters,low BSi,high LSi and high LSi/(LSi+BSi)ratios in the estuary,high BSi,LSi and high LSi/(LSi+BSi)ratios in the upwelling region.LSi and LSi/(LSi+BSi)ratios in the bottom water were higher than those in the surface water.In addition,some limitations caused by other methodologies of BSi measurements had been discussed.

关 键 词：生物硅 岩源硅 LSi/(LSi+BSi)比 Si/Al比 叶绿素a 黏土矿物 

分 类 号：P734.2[天文地球—海洋化学]