The importance of phytoplankton biomolecule availability for secondary production

The growth and reproduction of animals is affected by their access to resources. In aquatic ecosystems, the availability of essential biomolecules for filter-feeding zooplankton depends greatly on phytoplankton. Here, we analyzed the biochemical composition, i.e., the fatty acid, sterol and amino acid profiles and concentrations as well as protein, carbon, nitrogen, and phosphorus content of 17 phytoplankton monocultures representing the seven most abundant phytoplankton classes in boreal and sub-arctic lakes. To examine how the differences in the biochemical composition between phytoplankton classes affect their nutritional quality for consumers, we assessed the performance of Daphnia, on these diets. Furthermore, we defined the most important biomolecules regulating the somatic growth and reproduction of Daphnia, expecting that higher concentrations of certain biomolecules are needed for reproduction than for growth. Finally, we combined these results with phytoplankton field data fro...动物的生长与繁殖受其可获取的资源量影响。在水生生态系统中，滤食性浮游动物（filter-feeding zooplankton）所需关键生物分子的可获得性，很大程度上依赖于浮游植物（phytoplankton）。本研究分析了17种浮游植物单培养物的生化组成，即脂肪酸、甾醇与氨基酸的谱型与浓度，以及蛋白质、碳、氮、磷含量；所分析的浮游植物涵盖了北方与亚北极湖泊中7种丰度最高的浮游植物门类。为探究不同浮游植物门类间的生化组成差异如何影响其作为食物的营养品质，我们以这些浮游植物为饵料，评估了水蚤（Daphnia）的生长与繁殖表现。此外，我们还明确了调控水蚤体细胞生长与繁殖的关键生物分子，并提出假设：相较于体细胞生长，繁殖过程需要更高浓度的特定生物分子。最后，我们将上述研究结果与野外浮游植物实地数据相结合……