Benthic mats offer a potential subsidy to pelagic consumers in tundra pond food webs
Benthic mats offer a potential subsidy to pelagic consumers in tundra pond food webs
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底栖垫为苔原池塘食物网中的远洋消费者提供潜在的补贴
DOI：
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发表时间：
2014
期刊：
影响因子：
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通讯作者：
M. Rautio
中科院分区：
文献类型：
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作者：
H. Mariash;Shawn P. Devlin;L. Forsström;Roger I. Jones;M. Rautio
我们使用三种方法量化了苔原池塘中底栖垫对中上层消费者的潜在营养贡献。 (1) 我们根据藻类生物量和群落组成比较了底栖和中上层栖息地，并根据脂肪酸 (FA) 浓度评估了两个栖息地的饮食质量。不同栖息地的藻类群落组成存在显着差异。底栖和中上层生境均含有饱和和不饱和的 FA，但平均而言，在所有研究的池塘中，中上层生境 (44 ± 29 µg mg C−1) 中相对于碳的 FA 含量多于底栖生境 (23 ± 18 µg mg C−1)。 (2) 我们量化了底栖垫对全湖 FA 库的贡献，发现底栖垫在苔原池塘内的基础 FA 资源中占主导地位（平均> 90%）。 (3) 通过一系列饲养实验，我们发现当底栖垫浆补充低浓度的浮游植物时，水蚤的存活率和 FA 浓度增加。然而，水蚤不能仅在底栖垫上生存，并且当垫作为连贯的碎片提供时，底栖垫也不会增加成年水蚤的存活率。深海生产对中上层消费者的支持程度对以下观点提出了挑战：深海栖息地在功能上与北部湖泊生态系统中的中上层食物网是分离的。
We quantified the potential nutritional contribution of benthic mats to pelagic consumers in tundra ponds using three approaches. (1) We compared benthic and pelagic habitats based on their algal biomass and community composition and assessed the dietary quality in terms of fatty acid (FA) concentrations in both habitats. The algal community compositions differed significantly between habitats. Both benthic and pelagic habitats contained saturated and unsaturated FAs, but on average there were more FAs relative to carbon in the pelagic habitat (44 ± 29 µg mg C−1) than the benthic habitat (23 ± 18 µg mg C−1) across all studied ponds. (2) We quantified the contribution of benthic mats to the whole‐lake FA pool and found that benthic mats dominate (on average > 90%) the basal FA resource within tundra ponds. (3) Using a series of feeding experiments, we found that Daphnia survival and FA concentrations increased when a benthic mat slurry supplemented low concentrations of phytoplankton. However, Daphnia could not survive solely on benthic mats, and nor did benthic mats increase adult Daphnia survival when mats were offered as coherent pieces. The extent to which pelagic consumers could be supported by benthic production challenges the view that benthic habitats are functionally separate from the pelagic food webs within northern lake ecosystems.