Recent observations in marine ecosystems show that the presence of thiamine regulates primary production, but little is known about the ecological effect of thiamine in streams. We conducted nutrient enrichment experiments in four streams in the New York's Adirondack Mountains using nutrient diffusing substrates to evaluate the influence of thiamine (vitamin B₁) on the growth of stream periphyton. Contrasting treatments in our study included nutrient additions of thiamine (C₁₂H₁₇ClN₄OS·HCl), nitrogen (NH₄Cl), and phosphorus (NaH₂PO₄). Thiamine limitation occurred in 12 of 14 experiments conducted from June through October in 2015–2017, nitrogen limitation occurred in eight experiments, and phosphorus limitation in one experiment. The magnitude of response of periphyton to thiamine enrichment varied among seasons, years, and streams. The growth-enhancing effect on periphyton biomass from thiamine or nitrogen addition typically occurred between 8 and 32 d of incubation, though the periphyton accumulation rate declined after 16–24 d of incubation. Our results showed that thiamine is a limiting nutrient for primary producers in our study streams and its effect size is similar to that of nitrogen. These findings extend the prior recognition of thiamine's substantial influence on marine photosynthetic eukaryotes to having a similar role in freshwater ecosystems.

中文翻译：

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阿迪朗达克山溪流中附生生物的硫胺素限制

最近在海洋生态系统中的观察表明，硫胺素的存在调节初级生产，但对溪流中硫胺素的生态影响知之甚少。我们使用养分扩散基质在纽约阿迪朗达克山脉的四个溪流中进行了养分富集实验，以评估硫胺素（维生素 B ₁）对溪流附生生物生长的影响。我们研究中的对比处理包括添加硫胺素 (C ₁₂ H ₁₇ ClN ₄ OS·HCl)、氮 (NH ₄ Cl) 和磷 (NaH ₂ PO ₄）。2015-2017 年 6 月至 10 月进行的 14 次实验中有 12 次发生硫胺素限制，8 次实验中发生氮限制，1 次实验中发生磷限制。附生生物对硫胺素富集的反应程度因季节、年份和河流而异。硫胺素或氮添加对附生生物量的生长促进作用通常发生在孵育 8 至 32 天之间，尽管孵育 16-24 天后附生生物积累率下降。我们的结果表明，硫胺素是我们研究流中初级生产者的一种限制性营养素，其影响大小与氮相似。这些发现将硫胺素对海洋光合真核生物的重大影响的先前认识扩展到在淡水生态系统中具有类似作用。