Unimodal size scaling of phytoplankton growth and the size dependence of nutrient uptake and use
Unimodal size scaling of phytoplankton growth and the size dependence of nutrient uptake and use
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DOI：
10.1111/ele.12052
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发表时间：
2013-03-01
期刊：
影响因子：
8.8
通讯作者：
Rodriguez, Jaime
中科院分区：
文献类型：
--
作者：
Maranon, Emilio;Cermeno, Pedro;Rodriguez, Jaime
浮游植物的大小结构是远洋生态系统的生态学和海洋地球化学的关键，但细胞大小和最大生长率（max）之间的关系还没有得到很好的理解。我们使用的文化的22种海洋浮游植物从5门，从0.1至106立方米的细胞体积（Vcell），以确定实验的大小依赖的增长，代谢率，元素的化学计量和营养吸收。我们发现，最大和碳特定的光合作用峰值在中间细胞大小。最大氮吸收速率（VmaxN）与Vcell等比例缩放，而氮最小配额缩放为Vcell 0.84。因此，相对于它们的需求，大细胞具有高的吸收氮的能力和大的储存容量，但是它们的生长受到营养物转化为生物质的限制。小物种显示类似的体积比VmaxN相比，他们的较大的同行，但有更高的氮需求。我们认为，单峰尺度的浮游植物生长产生于独立于分类，大小相关的营养吸收，需求和同化的限制。
Phytoplankton size structure is key for the ecology and biogeochemistry of pelagic ecosystems, but the relationship between cell size and maximum growth rate (max) is not yet well understood. We used cultures of 22 species of marine phytoplankton from five phyla, ranging from 0.1 to 106 m3 in cell volume (Vcell), to determine experimentally the size dependence of growth, metabolic rate, elemental stoichiometry and nutrient uptake. We show that both max and carbon-specific photosynthesis peak at intermediate cell sizes. Maximum nitrogen uptake rate (VmaxN) scales isometrically with Vcell, whereas nitrogen minimum quota scales as Vcell0.84. Large cells thus possess high ability to take up nitrogen, relative to their requirements, and large storage capacity, but their growth is limited by the conversion of nutrients into biomass. Small species show similar volume-specific VmaxN compared to their larger counterparts, but have higher nitrogen requirements. We suggest that the unimodal size scaling of phytoplankton growth arises from taxon-independent, size-related constraints in nutrient uptake, requirement and assimilation.