BIOGENIC PARTICLE FLUXES IN THE EQUATORIAL PACIFIC: EVIDENCE FOR BOTH HIGH AND LOW PRODUCTIVITY DURING THE 1982-1983 EL NINO
BIOGENIC PARTICLE FLUXES IN THE EQUATORIAL PACIFIC: EVIDENCE FOR BOTH HIGH AND LOW PRODUCTIVITY DURING THE 1982-1983 EL NINO
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DOI：
10.1029/gb002i002p00129
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发表时间：
1988-06-01
影响因子：
5.2
通讯作者：
Collier, Robert
中科院分区：
文献类型：
--
作者：
Dymond, Jack;Collier, Robert
在1982-1983年厄尔尼诺南方涛动期间和之后，在赤道太平洋两个地点部署的沉积物收集器显示了这一事件的生物影响。与1982年12月开始的28个月期间的任何其他时间记录的通量相比，赤道以北1号站点的生物粒子通量在强烈ENSO影响的3个月期间至少低2倍。这些低粒子通量反映了初级生产因厄尔尼诺/南方涛动事件而预期的减少。令人惊讶的是，在第二个站点，11 N，生物颗粒通量测量在同一ENSO影响期间异常高。赤道以北生产力的明显增加似乎是北赤道逆流（NECC）和浅温跃层的相关隆起的流动增强的结果。所观察到的时间变化幅度的生物颗粒通量的生物成分的变化伴随着。在11 N站点的高碳通量期间是异常蛋白石通量的时间，而在ENSO期间在1 N观测到的低碳通量期间的颗粒通量是蛋白石的耗尽。这些模式似乎反映了硅藻生产力相对于球石藻生产力的优势条件下，更大的养分供应。
Sediment traps deployed at two sites in the equatorial Pacific during and following the 1982-1983 El Nino southern oscillation (ENSO) demonstrate the biological effects of this event. Biogenic particle fluxes for a site 1 north of the equator were at least a factor of 2 lower during a 3 month period of intense ENSO influence compared to fluxes recorded at any other time during a 28-month period beginning in December 1982. These low particle fluxes reflect the expected decrease in primary production in response to the ENSO event. Surprisingly, the biogenic particle fluxes measured at the second site, 11N, were anomalously high during this same ENSO-affected period. The apparent increase in productivity north of the equator seems to be a consequence of enhanced flow of the North Equatorial Countercurrent (NECC) and the associated doming of the shallow thermocline. The observed temporal variability in magnitude of the biogenic particle flux was accompanied by compositional changes in the biogenic components. The period of high carbon flux at the 11N site was a time of exceptional opal flux, while the particle flux during the period of low carbon flux observed at 1N during the ENSO was depleted in opal. These patterns appear to reflect the dominance of diatom productivity relative to coccolithophorid productivity during conditions of greater nutrient availability.