当前位置: X-MOL 学术Aquat. Microb. Ecol. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Effect of anthropogenic warming on microbial respiration and particulate organic carbon export rates in the sub-Antarctic Southern Ocean
Aquatic Microbial Ecology ( IF 1.4 ) Pub Date : 2018-11-02 , DOI: 10.3354/ame01889
EL Cavan , PW Boyd

ABSTRACT: Microbial respiration of particulate organic carbon (POC) is one of the key processes controlling the magnitude of POC export from the surface ocean and its storage on long timescales in the deep. Metabolic processes are a function of temperature, such that warming sea temperatures should increase microbial respiration, potentially reducing POC export. To investigate this in the Southern Ocean, we measured microbial oxygen consumption of large particles over a 10°C temperature range (summer maximum +8°C) to then estimate the decrease in export by 2100. Our results showed that POC-normalised respiration increased with warming. We estimate that POC export (scaled to primary production) could decrease by 17 ± 7% (SE) by 2100, using projected regional warming (+1.9°C) from the IPCC RCP 8.5 (‘business-as-usual’ scenario) for our sub-Antarctic site. Increased microbial respiration is one of many processes that will be altered by future climate change, which could all modify carbon storage in the future. Our estimate of the potential decline in carbon sequestration is within previous estimates from lab and field experiments, but higher than simple mechanistic models. To explore our results further, we used the metabolic theory of ecology (MTE) to determine the activation energy of microbial respiration, which was 0.9 eV. This is higher than classical MTE (0.6-0.7 eV), suggesting that sub-Antarctic microbes are particularly sensitive to temperature change. Such regional characteristics in the response of organisms to increased temperatures should be accounted for in large-scale or global model analyses to ensure that the results do not underestimate microbial responses to warming.

中文翻译:

人为变暖对亚南极南大洋微生物呼吸和颗粒有机碳输出率的影响

摘要:颗粒有机碳 (POC) 的微生物呼吸是控制表层海洋 POC 输出量及其在深海长期储存的关键过程之一。代谢过程是温度的函数,因此海洋温度升高会增加微生物呼吸,从而可能减少 POC 的输出。为了在南大洋对此进行调查,我们测量了大颗粒在 10°C 温度范围内(夏季最高 +8°C)的微生物耗氧量,然后估计到 2100 年出口的减少。我们的结果表明 POC 标准化呼吸增加随着变暖。我们估计,到 2100 年,根据 IPCC RCP 8 预测的区域变暖(+1.9°C),POC 出口(按初级生产规模计算)可能会减少 17 ± 7% (SE)。5(“一切照旧”场景)用于我们的亚南极站点。微生物呼吸增加是未来气候变化将改变的众多过程之一,这些过程都可能在未来改变碳储存。我们对碳封存潜在下降的估计在实验室和现场实验的先前估计范围内,但高于简单的机械模型。为了进一步探索我们的结果,我们使用生态学代谢理论 (MTE) 来确定微生物呼吸的活化能为 0.9 eV。这高于经典 MTE (0.6-0.7 eV),表明亚南极微生物对温度变化特别敏感。
更新日期:2018-11-02
down
wechat
bug