Thiamin (vitamin B1) content in phytoplankton and zooplankton in the presence of filamentous cyanobacteria
Thiamin (vitamin B1) content in phytoplankton and zooplankton in the presence of filamentous cyanobacteria
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DOI：
10.1002/lno.10949
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发表时间：
2018-11-01
影响因子：
4.5
通讯作者：
Hylander, Samuel
中科院分区：
文献类型：
--
作者：
Fridolfsson, Emil;Lindehoff, Elin;Hylander, Samuel
一些水生食物网中的顶级捕食者经常表现出由于硫胺素（维生素 B-1）缺乏而导致的繁殖失败率升高。硫胺素水平较低的原因尚不清楚，有关硫胺素从生产者（细菌和浮游植物）转移到更高营养水平的信息也很有限。一个主要问题是蓝藻水华是否会对水生系统中硫胺素的转移产生负面影响。通过波罗的海浮游生物群落和单一浮游植物物种的实验室实验，研究了丝状蓝藻对硫胺素从浮游植物向浮游动物转移的影响。实验表明，当暴露于高水平的蓝藻时，桡足类动物中的硫胺素含量会降低，尽管丝状蓝藻的硫胺素含量高于任何其他分析的浮游植物物种。尽管非蓝藻食物浓度很高，丝状蓝藻也对桡足类产卵产生负面影响。浮游植物物种组成影响总体硫胺素浓度，当甲藻相对丰度较高时，可用于转移的硫胺素相对较多。最后，当桡足类丰富时，浮游植物硫胺素水平较低，表明食草动物可能通过选择性摄食影响浮游植物群落中的硫胺素水平。总体而言，浮游植物群落中硫胺素的高水平并未反映在桡足类群落中。我们得出的结论是，夏季丝状蓝藻的存在可能会对浮游植物和桡足类硫胺素含量以及桡足类繁殖产生负面影响，从而降低硫胺素向较高营养级的转移，从而降低食物网通过桡足类将硫胺素转移到较高营养级的绝对能力。
Top predators in several aquatic food webs regularly display elevated reproductive failure, caused by thiamin (vitamin B-1) deficiency. The reasons for these low-thiamin levels are not understood and information about the transfer of thiamin from the producers (bacteria and phytoplankton) to higher trophic levels is limited. One main concern is whether cyanobacterial blooms could negatively affect thiamin transfer in aquatic systems. Laboratory experiments with Baltic Sea plankton communities and single phytoplankton species were used to study the effect of filamentous cyanobacteria on the transfer of thiamin from phytoplankton to zooplankton. Experiments showed that the thiamin content in copepods was reduced when exposed to elevated levels of cyanobacteria, although filamentous cyanobacteria had higher levels of thiamin than any other analyzed phytoplankton species. Filamentous cyanobacteria also had a negative effect on copepod egg production despite high concentrations of non-cyanobacterial food. Phytoplankton species composition affected overall thiamin concentration with relatively more thiamin available for transfer when the relative abundance of Dinophyceae was higher. Finally, phytoplankton thiamin levels were lower when copepods were abundant, indicating that grazers affect thiamin levels in phytoplankton community, likely by selective feeding. Overall, high levels of thiamin in phytoplankton communities are not reflected in the copepod community. We conclude that presence of filamentous cyanobacteria during summer potentially reduces the transfer of thiamin to higher trophic levels by negatively affecting phytoplankton and copepod thiamin content as well as copepod reproduction, thereby lowering the absolute capacity of the food web to transfer thiamin through copepods to higher trophic levels.