硅壳和细胞内含物对硅藻沉降速率的影响  

Effect of Shell and Cell Inclusion on The Sinking Rate of Diatom

作　　者：张萍 陆家昌[2,3] 李朗 石天应 赖俊翔 庄军莲[2,3] 李杰 ZHANG Ping;LU Jiachang;LI Lang;SHI Tianying;LAI Junxiang;ZHUANG Junlian;LI Jie(School of Resources,Environment and Materials,Guangxi University,Nanning 530004,China;Guangxi Key Laboratory of Marine Environmental Science,Guangxi Academy of Marine Sciences,Guangxi Academy of Sciences,Nanning 530007,China;Beibu Gulf Marine Industry Research Institute,Fangchenggang 538000,China)

机构地区：[1]广西大学资源环境与材料学院,广西南宁530004 [2]广西科学院广西海洋科学院,广西近海海洋环境科学重点实验室,广西南宁530007 [3]北部湾海洋产业研究院,广西防城港538000

出　　处：《海洋环境科学》2023年第6期927-934,共8页Marine Environmental Science

基　　金：广西自然科学基金(2021GXNSFBA075011)。

摘　　要：硅藻沉降是海洋碳汇的重要途径,其速率影响生物泵效率。为了解硅壳和细胞内含物对硅藻沉降速率的影响,本文以北部湾处于指数生长期的17种常见硅藻为例,通过SETCOL法测定活细胞、热致死细胞(含硅壳和完整细胞内含物,但无细胞活性)和硅壳的沉降速率。结果表明,硅藻活细胞、热致死细胞和硅壳的沉降速率与粒径均存在极显著的正线性相关关系(p<0.01)。不同粒径范围内硅壳和细胞内含物对沉降速率的影响不同,小于25μm硅藻的沉降速率主要受硅壳影响,25μm到65μm硅藻的沉降速率均受硅壳和细胞内含物的共同影响,像哈德掌状藻这样的大型硅藻,其沉降速率则主要受细胞内含物的影响。总体上看,随粒径的增加,硅藻细胞沉降速率受硅壳的影响减弱,受内含物的影响增强。沉降速率受硅壳主导的硅藻,大部分具有通过表面突出物与其他细胞相连的能力;而沉降速率受细胞内含物主导的硅藻,通常体积较大,细胞间相互独立,可以灵活地对沉降速率进行调节。Diatom sedimentation is an important carbon sink in the ocean,and its rate affects the efficiency of the biological pump.To understand the effects of diatom shell and cell inclusion on the sinking rate of diatom,the sinking rate of live cell,heat killed cell(containing diatom shells and intact cell inclusions but without activity)and diatom shell of 17 common diatom species in Beibu Gulf were measured using SETCOL method during the exponential phase.The results showed that the sinking rate of live diatom,heat killed cells and silica shells were positively linearly correlated with their size(P<0.01).The role of diatom shells and cell inclusions in determining sinking rate was different according to the range of size.The sinking rate of<25µm diatoms was mainly determined by its shell and the sinking rate of 25µm to 65µm diatoms were influenced by both their shell and inclusions.While the sinking rate of large diatom such as Palmeria hardmaniana,was mainly determined by cell inclusion.Generally,the effects of diatom shells on sinking rate decreased with increasing cell size;in contrast,the effects of cell inclusions increased with increasing size.Most of the diatoms,which sinking rate was dominated by their shell,have an ability to connect with other cells by their surface protrusions;however,the species,which sinking rate was dominated by their inclusions,are independent and usually have a large size and flexible in sinking regulation.

关 键 词：硅藻 沉降速率 碳沉降 SETCOL法 

分 类 号：Q178.53[生物学—水生生物学]