Quantitative analysis of food web dynamics in a low export ecosystem
Quantitative analysis of food web dynamics in a low export ecosystem
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低出口生态系统中食物网动态的定量分析
DOI：
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发表时间：
2023
期刊：
影响因子：
--
通讯作者：
T. Rynearson
中科院分区：
文献类型：
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作者：
Heather Mcnair;M. G. Meyer;Sarah J. Lerch;Amy E. Maas;B. Stephens;James Fox;K. Buck;S. M. Burns;I. Cetinić;Melanie R. Cohn;C. Durkin;S. Gifford;W. Gong;Jason R. Graff;B. Jenkins;Erin L. Jones;A. Santoro;C. Shea;K. Stamieszkin;D. Steinberg;A. Marchetti;C. Carlson;S. Menden‐Deuer;M. Brzezinski;D. Siegel;T. Rynearson
食物网追踪有机物质和能量在生产者和消费者之间的流动；对于远洋海洋食物网，网络复杂性直接影响通过生物泵向深海输出的碳的数量和形式。在这里，我们对2018年夏末在东北太平洋亚北极地区长期时间序列站点Papa海洋站进行的海洋遥感出口过程（EXPORTS）现场活动中观测到的混合层食物网动态进行了概貌分析。浮游植物、微型浮游动物和浮游细菌的碳储量基本相等，而中浮游动物的碳储量则低70%。活生物体占混合层中总颗粒有机碳的约40%，其余部分来自碎屑。储集层之间的碳转移率表明，产量和同化率与损失很好地平衡，留下很少的有机碳可供出口。微正的净群落生产速率产生的有机碳以食物网副产品的形式从系统输出，例如中浮游动物产生的大粪便颗粒。这种典型的再生食物网具有相对较慢的周转时间，相对于在高背景浓度的碎屑颗粒和溶解有机质中发生的常存储量，碳的转移规模较小。对食物网成分和速率的同时估计表明，与那些促进出口的过程相比，分离过程在食物网内的碳转移中占主导地位。生物碳泵驱动有机物从阳光照射的海洋表面向广阔的海洋内部向下流动。海洋表层的生态相互作用直接影响向深海输出的碳的数量和类型。在本研究中，我们综合了东北太平洋夏末混合层食物网，该食物网在2018年海洋遥感出口过程（EXPORTS）现场活动中得到了广泛表征。我们发现大部分碳在混合层内通过生产者和消费者之间的多次转移被微生物回收。较大的生物，如中浮游动物和海鞘，只消耗少量的碳，但通过形成下沉的粪便颗粒是将碳运出系统的主要机制。这项研究强调了同时研究微生物和大型生物动力学的必要性，以发展对海洋中有机碳命运的预测性理解。在北太平洋夏末混合层食物网中，微生物循环主导了碳流，大部分净产量被呼吸，留下很少的碳可供出口。有机碳的活跃生产和消耗发生在碎屑颗粒有机碳的高背景下（占总有机碳的58%），周转时间较慢，为66 d。由于对消耗的材料进行了有效的再包装，碳消耗率相对较小的中浮游动物创造了大部分出口产量。
Food webs trace the flow of organic matter and energy among producers and consumers; for pelagic marine food webs, network complexity directly influences the amount and form of carbon exported to the deep ocean via the biological pump. Here we present a synoptic view of mixed layer food web dynamics observed during the late summer 2018 EXport Processes in the Ocean from Remote Sensing (EXPORTS) field campaign in the subarctic Northeast Pacific at the long-running time-series site, Ocean Station Papa. Carbon biomass reservoirs of phytoplankton, microzooplankton, and bacterioplankton, were approximately equal while mesozooplankton biomass was 70% lower. Live organisms composed ∼40% of the total particulate organic carbon within the mixed layer: the remainder was attributed to detritus. Rates of carbon transfer among reservoirs indicated production and assimilation rates were well balanced by losses, leaving little organic carbon available for export. The slight positive net community production rate generated organic carbon that was exported from the system in the form of food web byproducts, such as large fecal pellets generated by mesozooplankton. This characteristically regenerative food web had relatively slow turnover times with small-magnitude transfers of carbon relative to standing stocks that occurred amidst a high background concentration of detrital particles and dissolved organic matter. The concurrent estimation of food web components and rates revealed that separated processes dominated the transfer of carbon within the food web compared to those that contributed to export. Plain Language Summary The biological carbon pump drives a downward flux of organic matter from the sunlit surface ocean to the vast ocean interior. Ecological interactions in the surface ocean directly affect the amount and type of carbon that is exported to the deep ocean. In this study, we present a synthesis of the late summer mixed layer food web in the Northeast Pacific that was extensively characterized during the 2018 EXport Processes in the Ocean from Remote Sensing (EXPORTS) field campaign. We found the majority of carbon was recycled within the mixed layer by microbes through multiple transfers between producers and consumers. Larger organisms, mesozooplankton and salps, only consumed a small amount of carbon but through the formation of sinking fecal pellets were the main mechanism of transporting carbon out of the system. The study highlights the need to concurrently study microbial and large organism dynamics to develop a predictive understanding of the fate of organic carbon in the oceans. Key Points The microbial loop dominated carbon flow in the late summer mixed layer food web of the North Pacific, most net production was respired leaving little carbon available for export. Active production and consumption of organic carbon occurred amid a high background of detrital particulate organic carbon (58% of total) with slow turnover time, 66 d. Mesozooplankton which had relatively minor carbon consumption rates created the majority of export production due to efficient repackaging of consumed material.
DOI：
10.1525/elementa.2020.00107
发表时间：
2021
期刊：
Elementa: Science of the Anthropocene
影响因子：
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作者：
David A. Siegel;I. Cetinić;Jason R. Graff;Craig M. Lee;N. Nelson;M. Perry;I. S. Ramos;D. Steinberg-D.
通讯作者：
David A. Siegel;I. Cetinić;Jason R. Graff;Craig M. Lee;N. Nelson;M. Perry;I. S. Ramos;D. Steinberg-D.
影响因子：
4.5
作者：
Moran, Mary Ann;Ferrer-Gonzalez, Frank X.;Uchimiya, Mario
通讯作者：
Uchimiya, Mario
DOI：
10.1038/s43705-023-00314-9
发表时间：
2023-10-02
期刊：
ISME COMMUNICATIONS
影响因子：
--
作者：
Sharpe, Garrett;Zhao, Liang;Meyer, Meredith G;Gong, Weida;Burns, Shannon M;Tagliabue, Allesandro;Buck, Kristen N;Santoro, Alyson E;Graff, Jason R;Marchetti, Adrian;Gifford, Scott
通讯作者：
Gifford, Scott