当前位置: X-MOL 学术Glob. Biogeochem. Cycles › 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.)
Euphotic Zone Metabolism in the North Pacific Subtropical Gyre Based on Oxygen Dynamics
Global Biogeochemical Cycles ( IF 5.2 ) Pub Date : 2021-02-09 , DOI: 10.1029/2020gb006744
Sara Ferrón 1 , Benedetto Barone 1 , Matthew J. Church 2 , Angelicque E. White 1 , David M. Karl 1
Affiliation  

We report in situ rates of gross oxygen production (GOP), community respiration (R), and net community production (NCP) in the North Pacific Subtropical Gyre derived from mixed layer O2/Ar measurements. The measurements were conducted between November 2013 and January 2019 at the site of the Hawaii Ocean Time‐series program. Biological O2 concentration anomalies in the mixed layer showed a consistent diel variation, with values increasing during daytime due to net community production and decreasing during nighttime due to respiration. In situ mixed layer GOP and R, determined from these variations, covaried but showed no clear seasonal pattern, averaging 0.9 and 0.8 mmol O2 m−3 d−1, respectively. In situ rates of NCP determined from mixed layer O2/Ar ranged between −1.2 and 16.6 mmol O2 m−2 d−1. Our analyses indicate that at certain times of the year the diapycnal flux of O2 across the base of the mixed layer may be non‐negligible and, therefore, a fraction of O2/Ar‐derived NCP may form below the mixed layer. The seasonal climatology of NCP below the mixed layer (down to 150 m) was also estimated using near‐monthly changes in dissolved O2 concentrations. These calculations allowed us to estimate NCP for the entire euphotic zone (0–150 m), which shows pronounced seasonality, with a maximum in April‐May and a minimum in December, when the ecosystem becomes temporarily net heterotrophic. Annual NCP was estimated to be 2.1 ± 0.6 mol O2 m−2 yr−1, approximately 1.7 times the export of C through sinking particles captured in sediment traps at 150 m.

中文翻译:

基于氧气动力学的北太平洋亚热带回旋区的富营养区新陈代谢

我们报告了从混合层O 2 / Ar测量得出的北太平洋亚热带回旋带中的总氧生产(GOP),社区呼吸(R)和净社区生产(NCP)的原位速率。这些测量是在2013年11月至2019年1月之间在夏威夷海洋时间序列计划的站点进行的。混合层中的生物O 2浓度异常表现出一致的diel变化,其值在白天由于净群落产生而增加,而在夜间由于呼吸而减小。由这些变化确定的原位混合层GOP和R共变,但没有明显的季节性变化,平均为0.9和0.8 mmol O 2  m -3  d -1, 分别。由混合层O 2 / Ar确定的NCP的原位速率在-1.2至16.6mmol O 2  m -2  d -1之间。我们的分析表明,在一年中的某些时候,穿过混合层底部的O 2的径向通量可能是不可忽略的,因此,一部分O 2 / Ar衍生的NCP可能在混合层以下形成。混合层以下(低至150 m)NCP的季节性气候也可以通过溶解氧2的近月变化来估算浓度。这些计算使我们能够估算整个富营养区(0-150 m)的NCP,这显示了明显的季节性,当生态系统暂时变为净异养型时,最大值出现在4月至5月,最小值出现在12月。每年的NCP估计为2.1±0.6 mol O 2  m -2  yr -1,大约是150 m处通过沉积物捕集阱中捕获的沉降颗粒排放的C的1.7倍。
更新日期:2021-03-17
down
wechat
bug