The Role of Microbes in the Nutrition of Detritivorous Invertebrates: A Stoichiometric Analysis.
The Role of Microbes in the Nutrition of Detritivorous Invertebrates: A Stoichiometric Analysis.
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DOI：
10.3389/fmicb.2016.02113
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发表时间：
2016
影响因子：
5.2
通讯作者：
Mayor DJ
中科院分区：
文献类型：
--
作者：
Anderson TR;Pond DW;Mayor DJ
碎屑是全球碳循环中的一个重要来源，为几乎所有生态系统的重要组成部分-食腐无脊椎动物提供了食物来源。然而，我们对这些生物体如何通过通常由难熔的富碳化合物组成的饮食来满足其营养需求的知识仍然不完整。附着的微生物群落对碎屑的“营养升级”（通过加入异养原生动物来增强浮游动物的饮食）代表了食虫动物的潜在营养来源，因为细菌及其有鞭毛的原生生物捕食者都能够生物合成必需的微量营养素，如多不饱和脂肪酸（PUFA）。然而，这是一种权衡，因为尽管微生物在微量营养素含量方面提高了基质，但随着能量通过微生物食物网，有机碳的数量通过代谢损失而减少。在这里，我们开发了一个简单的化学计量模型来研究这种权衡的营养的嗜食桡足类栖息在海洋中层区，专注于他们的碳和必需的多不饱和脂肪酸，二十二碳六烯酸（DHA）的要求。结果表明，微生物上的饲料可能是这些无脊椎动物的一个非常有利的策略，虽然潜在的碳成为限制时，消费的微生物饮食存在，因为营养转移的微生物食物网内的效率低下。我们的研究强调了在碎屑-微生物-后生动物界面，包括相关生物的生理和生态之间的相互作用，需要改进的知识。
Detritus represents an important pool in the global carbon cycle, providing a food source for detritivorous invertebrates that are conspicuous components of almost all ecosystems. Our knowledge of how these organisms meet their nutritional demands on a diet that is typically comprised of refractory, carbon-rich compounds nevertheless remains incomplete. “Trophic upgrading” of detritus by the attached microbial community (enhancement of zooplankton diet by the inclusion of heterotrophic protozoans) represents a potential source of nutrition for detritivores as both bacteria and their flagellated protistan predators are capable of biosynthesizing essential micronutrients such as polyunsaturated fatty acids (PUFAs). There is however a trade-off because although microbes enhance the substrate in terms of its micronutrient content, the quantity of organic carbon is diminished though metabolic losses as energy passes through the microbial food web. Here, we develop a simple stoichiometric model to examine this trade-off in the nutrition of detritivorous copepods inhabiting the mesopelagic zone of the ocean, focusing on their requirements for carbon and an essential PUFA, docosahexaenoic acid (DHA). Results indicate that feeding on microbes may be a highly favorable strategy for these invertebrates, although the potential for carbon to become limiting when consuming a microbial diet exists because of the inefficiencies of trophic transfer within the microbial food web. Our study highlights the need for improved knowledge at the detritus-microbe-metazoan interface, including interactions between the physiology and ecology of the associated organisms.