Role of ENSO Conditions on Particulate Organic Matter Concentrations and Elemental Ratios in the Southern California Bight
Role of ENSO Conditions on Particulate Organic Matter Concentrations and Elemental Ratios in the Southern California Bight
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DOI：
10.3389/fmars.2019.00386
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发表时间：
2019-07-11
影响因子：
3.7
通讯作者：
Martiny, Adam C.
中科院分区：
文献类型：
--
作者：
Fagan, Adam J.;Moreno, Allison R.;Martiny, Adam C.
厄尔尼诺/南方涛动（ENSO）影响许多太平洋区域海表温度和上升流强度的多年变化。然而，目前尚不清楚厄尔尼诺条件将如何影响颗粒有机物（POM）的浓度和元素比例。为了调查这一点，我们在南加州湾的MICRO时间序列站每周量化POM 6年（2012年至2017年）。我们发现，2015年厄尔尼诺现象对海表温度和磷酸盐浓度有很大影响，但对硝酸盐可用性的影响较小。2015年厄尔尼诺现象也导致POC和POP浓度的短期下降，而PON浓度显示出独立的长期下降，无论厄尔尼诺事件如何。2015年厄尔尼诺导致的POM浓度降低与高C：P和N：P比率平行发生。随着PON的变化，C：N继续攀升，在我们的采样期结束时达到9.4。我们认为，东太平洋与中太平洋型厄尔尼诺以及太平洋年代际振荡阶段的开关显着改变了本地的POM浓度和比例的响应。
El Nino Southern Oscillation (ENSO) influences multi-year variation in sea-surface temperature and the intensity of upwelling in many Pacific regions. However, it is currently unknown how El Nino conditions will affect the concentration and elemental ratios of particulate organic matter (POM). To investigate this, we have quantified POM weekly for 6 years (2012 to 2017) at the MICRO time-series station in the Southern California Bight. We found a strong influence of the 2015 El Nino on seasurface temperature and phosphate concentration but to a lesser extent on nitrate availability. The 2015 El Nino also resulted in a short-term depression in POC and POP concentrations, whereas PON concentrations displayed an independent long-term decline regardless of the El Nino event. Reduced POM concentrations resulting from the 2015 El Nino occurred in parallel to high C:P and N:P ratios. Following the changes in PON, C:N continued to climb reaching similar to 9.4 at the end of our sampling period. We suggest that an Eastern Pacific- vs. a Central Pacific-type El Nino as well as a switch in the Pacific Decadal Oscillation phase significantly altered the local response in POM concentrations and ratios.