Mass-specific respiration of mesozooplankton and its role in the maintenance of an oxygen-deficient ecological barrier (BEDOX) in the upwelling zone off Chile upon presence of a shallow oxygen minimum zone
Mass-specific respiration of mesozooplankton and its role in the maintenance of an oxygen-deficient ecological barrier (BEDOX) in the upwelling zone off Chile upon presence of a shallow oxygen minimum zone
复制标题
DOI：
10.1016/j.jmarsys.2013.05.011
复制
发表时间：
2014-01-01
影响因子：
2.8
通讯作者：
Escribano, Ruben
中科院分区：
文献类型：
--
作者：
Donoso, Katty;Escribano, Ruben
智利近海上升流带的浅氧极小区(OMZ)可能会垂直地将大多数浮游动物限制在狭窄的上层(<；50米)。通过实验室实验，我们估计了2010年5月、2010年12月和2011年8月在智利北部梅吉隆斯湾(S 23度)获得的中游动物群落的耗氧量。在12摄氏度的平均温度下，质量比呼吸速率在8.2-24.5µmolO-2 mg干质量(-1)天(-1)的范围内。对水柱中中浮游动物生物量的估计表明，它的有氧呼吸每天最多可去除氧跃层底部约20%的可用氧。由于以前的工作表明浮游动物聚集在氧跃层底部附近，有氧呼吸对氧含量的影响可能在这个深度更大。中游动物的呼吸、氧跃层底部附近微生物的群落呼吸以及强烈的层结条件(限制O-2的垂直通量)被认为是造成和维持上升流带持续的地下缺氧生态屏障(BEDOX)的关键因素。这一BEDOX层可以在影响和调节洪堡洋流系统高生产力沿海上升流区浮游动物的分布和动态方面发挥重要作用。(C)2013爱思唯尔B.V.保留所有权利。
A shallow oxygen minimum zone (OMZ) in the coastal upwelling zone off Chile may vertically confine most zooplankton to a narrow (< 50 m) upper layer. From laboratory experiments, we estimated oxygen consumption of the mesozooplankton community obtained in Bay of Mejillones, northern Chile (23 degrees S) in May 2010, December 2010 and August 2011. Mass-specific respiration rates were in the range of 8.2-24.5 mu mol O-2 mg dry mass(-1) day(-1), at an average temperature of 12 degrees C. Estimates of the mesozooplankton biomass in the water column indicated that its aerobic respiration may remove daily a maximum of about 20% of oxygen available at the base of the oxycline. Since previous work indicates that zooplankton aggregate near the base of the oxycline, the impact of aerobic respiration on oxygen content might be even stronger at this depth. Mesozooplankton respiration, along with community respiration by microorganisms near the base of the oxycline and a strongly stratified condition (limiting vertical flux of O-2), are suggested as being critical factors causing and maintaining a persistent subsurface oxygen-deficient ecological barrier (BEDOX) in the upwelling zone. This BEDOX layer can have a major role in affecting and regulating zooplankton distribution and their dynamics in the highly productive coastal upwelling zone of the Humboldt Current System. (c) 2013 Elsevier B.V. All rights reserved.