Episodic organic carbon fluxes from surface ocean to abyssal depths during long-term monitoring in NE Pacific.
Episodic organic carbon fluxes from surface ocean to abyssal depths during long-term monitoring in NE Pacific.
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DOI：
10.1073/pnas.1814559115
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发表时间：
2018-11-27
影响因子：
11.1
通讯作者：
Kahru M
中科院分区：
文献类型：
--
作者：
Smith KL Jr;Ruhl HA;Huffard CL;Messié M;Kahru M
忽视海洋碳收支的时间波动导致对有机物质从表层水域的生产到深海的消费和封存的循环的严重歪曲。29年(至2017年)的颗粒有机碳(POC)通量时间序列和海底沉积物群落耗氧量(SCOC)的测量揭示了过去7年来断断续续的高强度事件。卫星估计的出口通量、POC通量和SCOC变化之间的时间间隔从0天到70天不等。一种常用的估算通过水柱的碳通量的模型大大低估了测量的碳通量近50%。必须计算进入深海的有机碳的间歇性脉冲，以平衡海洋碳收支。越来越多的证据表明，在周期性通量事件期间，地表水中产生的大量颗粒有机碳(POC)在几天内就会到达深海深处。利用29年的现场观测记录，研究了M站(东北太平洋，4000米水深)POC通量和沉积物群落耗氧量(SCOC)的幕式峰值。从到2017年，19%的3,400米POC通量是在高震级事件(≥Mean+2σ)期间到达的，从2011年到2017年，这一比例为43%。从2011年到2017年，当有高分辨率的SCOC数据时，卫星估计的出口通量(EF)、POC通量和海底SCOC的变化之间的时间滞后在0到70天的6个通量事件之间变化，这表明再矿化率和/或颗粒下沉速度不同。一半的PoC通量脉冲事件与先前的EF增加和/或随后的SCOC增加相关。位于M站上方的EF峰值经常转化为深海POC通量的变化。利用幂函数模型(Martin曲线)估算了深海通量与中层水温的关系。模式能很好地描述3,400m深度的背景POC通量，但对幕式事件的∼估计偏低80%，对总通量的估计偏低近50%。量化有机碳进入深海的周期性脉冲对于模拟POC固存的深度和强度以及理解全球碳循环至关重要。
Ignoring temporal fluctuations in the oceanic carbon budget leads to a significant misrepresentation of the cycling of organic matter from production in surface waters to consumption and sequestration in the abyssal ocean. A 29-year time series (1989 to 2017) of particulate organic carbon (POC) fluxes and sea-floor measurements of sediment community oxygen consumption (SCOC) revealed episodic, high-magnitude events over the past 7 years. Time lags between changes in satellite-estimated export flux, POC flux and SCOC varied from 0 to 70 days. A commonly used model to estimate carbon flux through the water column significantly underestimated the measured carbon fluxes by almost 50%. Episodic pulses of organic carbon into the deep sea must be accounted for to balance the oceanic carbon budget. Growing evidence suggests substantial quantities of particulate organic carbon (POC) produced in surface waters reach abyssal depths within days during episodic flux events. A 29-year record of in situ observations was used to examine episodic peaks in POC fluxes and sediment community oxygen consumption (SCOC) at Station M (NE Pacific, 4,000-m depth). From 1989 to 2017, 19% of POC flux at 3,400 m arrived during high-magnitude episodic events (≥mean + 2 σ), and 43% from 2011 to 2017. From 2011 to 2017, when high-resolution SCOC data were available, time lags between changes in satellite-estimated export flux (EF), POC flux, and SCOC on the sea floor varied between six flux events from 0 to 70 days, suggesting variable remineralization rates and/or particle sinking speeds. Half of POC flux pulse events correlated with prior increases in EF and/or subsequent SCOC increases. Peaks in EF overlying Station M frequently translated to changes in POC flux at abyssal depths. A power-law model (Martin curve) was used to estimate abyssal fluxes from EF and midwater temperature variation. While the background POC flux at 3,400-m depth was described well by the model, the episodic events were significantly underestimated by ∼80% and total flux by almost 50%. Quantifying episodic pulses of organic carbon into the deep sea is critical in modeling the depth and intensity of POC sequestration and understanding the global carbon cycle.
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DOI：
10.1016/j.dsr.2018.08.007
发表时间：
2018-10-01
影响因子：
2.4
作者：
Kelly, Thomas B.;Goericke, Ralf;Stukel, Michael R.
通讯作者：
Stukel, Michael R.
影响因子：
64.8
作者：
Guidi L;Chaffron S;Bittner L;Eveillard D;Larhlimi A;Roux S;Darzi Y;Audic S;Berline L;Brum J;Coelho LP;Espinoza JCI;Malviya S;Sunagawa S;Dimier C;Kandels-Lewis S;Picheral M;Poulain J;Searson S;Tara Oceans coordinators;Stemmann L;Not F;Hingamp P;Speich S;Follows M;Karp-Boss L;Boss E;Ogata H;Pesant S;Weissenbach J;Wincker P;Acinas SG;Bork P;de Vargas C;Iudicone D;Sullivan MB;Raes J;Karsenti E;Bowler C;Gorsky G
通讯作者：
Gorsky G
影响因子：
64.8
作者：
Horton, Daniel E.;Johnson, Nathaniel C.;Diffenbaugh, Noah S.
通讯作者：
Diffenbaugh, Noah S.
影响因子：
64.8
作者：
Huntingford, Chris;Jones, Philip D.;Cox, Peter M.
通讯作者：
Cox, Peter M.
影响因子：
4.5
作者：
Lebrato, Mario;Mendes, Pedro de Jesus;Oschlies, Andreas
通讯作者：
Oschlies, Andreas