The diel vertical migration of sound scatterers observed by an acoustic Doppler current profiler in the Luzon Strait from July 2009 to April 2011
The diel vertical migration of sound scatterers observed by an acoustic Doppler current profiler in the Luzon Strait from July 2009 to April 2011
复制标题
2009年7月至2011年4月吕宋海峡声多普勒海流剖面仪观测到的声散射体的昼夜垂直迁移
DOI：
10.1007/s13131-013-0371-8
复制
发表时间：
2013
影响因子：
1.4
通讯作者：
Zhu Xiaohua
中科院分区：
文献类型：
--
作者：
Yang Chenghao;Liao Guanghong;Yuan Yaochu;Chen Hong;Zhu Xiaohua
声学多普勒海流剖面仪（ADCP）接收来自声散射体的回波，利用多普勒效应计算其流速。在开阔的海洋中，这些后向散射体大多来自浮游生物。在吕宋海峡，声散射体在黎明前后下降到深层，平均速度为2.9cm/s，然后在黄昏前后上升到表层，平均速度为2.1cm/s。下降速度较快，表明该浮游动物种群在重力作用下可能加速向下迁移。夜间平均体积后向散射强度（MVBS）的垂直分布有两个峰值，分别位于盐跃层的上、下边界层附近。然而，后向散射体在白天仅聚集在近地层附近。声散射体的昼夜垂直迁移具有多种特征，夏季较强，冬季较弱，最大峰值出现在9月。DVM的发生与海水温度的上升同步，可能影响海洋混合和水层化。
Acoustic Doppler current profiler (ADCP) receives echoes from sound scatterers, then their speed is calculated by the Doppler effect. In the open ocean, most of these backscatterers are from the plankton. The sound scatterers descend down to depth at around dawn, their mean speed is 2.9 cm/s, then they ascend up to the surface layer at around dusk with a mean speed of 2.1 cm/s, in the Luzon Strait. The descending speed is faster, which suggests that this zooplankton population may accelerate its downward migration under the action of the gravity. The vertical distribution of a mean volume backscattering strength (MVBS) in the nighttime has two peaks, which locate near the upper and lower boundary layers of halocline, respectively. However, the backscatterers only aggregate near the surface layer in the daytime. The diel vertical migration (DVM) of sound scatterers has several characteristic patterns, it is stronger in summer, but weaker in winter, and the maximum peak occurs in September. The DVM occurrence is synchronous with the seawater temperature increasing at around dawn and dusk, it may affect the ocean mixing and water stratification.