Across-slope relations between the biological populations, the euphotic zone and the oxygen minimum layer off the coast of Oman during the southwest monsoon (August, 1994)
Across-slope relations between the biological populations, the euphotic zone and the oxygen minimum layer off the coast of Oman during the southwest monsoon (August, 1994)
复制标题
西南季风期间阿曼海岸生物种群、富光带和最低含氧层之间的跨坡关系（1994年8月）
DOI：
10.1016/s0079-6611(98)00019-6
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发表时间：
1998
影响因子：
4.1
通讯作者：
M. Angel
中科院分区：
文献类型：
--
作者：
P. Herring;M. Fasham;A. Weeks;J. Hemmings;H. Roe;P. Pugh;S. Holley;N. Crisp;M. Angel
1994年8月，对阿曼东海岸120×70km附近的一个地区（包括联合王国联合地面观测系统Arabesque站）进行了为期17天的深入研究，目的是确定生物种群、最低氧层和光带动态水文之间的关系。该区域的外缘由15个全深度CTD铸件组成的矩形划定，并通过两次Seasoar测量进一步确定了水道。采用中水拖网分别在海洋、坡面和陆架边缘3个站点采集种群。在每个站点采集大型浮游生物和微型浮游生物的昼夜样本，以确定diel垂直迁移的程度以及缺氧地区对这些迁移的影响。并发ADCP数据用于实时跟踪迁移和空间变化。虽然研究面积有限，但上升流的时空变化规律较为复杂。在两次Seasoar调查期间，仅在该地区的西南边缘直接观察到沿海上升流。在200 - 300米深度处，波斯湾水域是一个一致但空间离散的特征。阿拉伯海地表水出现在第一次调查的东部边缘。在这两个水团之间是一个面积大、水平梯度小、硅酸盐和叶绿素含量多变的区域。卫星数据显示，这些水可能是从更北的海岸来源以细丝形式平流而来。在两次访问之间的16天内，19°N - 59°E参考站的水文特征和浮游植物组成及丰度发生了非常显著的变化。浮游生物和微浮游生物（以湿体积或碳表示）的最高生物量出现在100m以上，与这些深度相对较高的氧含量密切相关。胶状动物在这些层中占主导地位，另外还有成群的游泳蟹。白天，在二氧层下有大量的嗜菌鱼、光鱼和十足甲壳类动物。其中大部分在夜间迁移到表层，留下的生物量很少，结果是夜间从氧斜层下获得的ADCP反向散射数据往往低于仪器分辨率。另一方面，白天ADCP数据显示出多个细层，其中一些与盐度差异相关。在最低含氧量层的底部，有大量的生物量增加，标志着一个更典型的深海动物群的存在。
An area some 120×70km off the eastern coast of Oman (containing the UK JGOFS Arabesque station) was intensively studied over a 17 day period in August 1994, with the objective of determining the relationships between the biological populations, the oxygen minimum layer and the dynamic hydrography of the euphotic zone. The outer margin of the area was delimited by a rectangle of 15 full depth CTD casts and the hydrography was further defined by two Seasoar surveys within the box. Midwater trawls were used to sample the populations at three stations, oceanic, slope and shelf edge respectively. Day and night samples of macroplankton and micronekton were taken at each station to determine the extent of diel vertical migration and the effect of the hypoxic region on these migrations. Concurrent ADCP data were used to follow the migrations and spatial changes in real time. Despite the limited area studied the patterns of upwelling and their temporal and spatial changes were complex. Coastal upwelling was observed directly only at the southwestern edge of the area during both Seasoar surveys. Persian Gulf Water was a consistent but spatially discrete feature of the region at depths of 200–300m. Arabian Sea Surface Water was present at the eastern margin of the first survey. Between these two water masses was a large area with small horizontal gradients and variable silicate and chlorophyll levels. Satellite data suggest that this water may have been advected as a filament from a more northerly coastal source. Very marked changes took place in the hydrography and in the phytoplankton composition and abundance at the reference station at 19°N 59°E over the 16 day period between visits. The highest biomass of plankton and micronekton (expressed as wet volume or as carbon) occurred in the upper 100m, closely correlated with the relatively high oxygen levels at these depths. Gelatinous animals predominated in these layers, with additional swarms of swimming crabs. Quite large populations of myctophid and photichthyid fishes and of decapod crustaceans were present below the oxycline by day. Most of these migrated into the surface layers at night, leaving minimal biomass behind, with the result that the ADCP backscatter data from beneath the oxycline at night were often below instrument resolution. Daytime ADCP data, on the other hand, showed multiple fine layering, some of which correlated with salinity differences. At the base of the oxygen minimum layer there was a large increase in biomass, marking the presence of a more typical bathypelagic fauna.