An abrupt decline in springtime zooplankton diel vertical migration due to a shift in stratification regime
An abrupt decline in springtime zooplankton diel vertical migration due to a shift in stratification regime
复制标题
由于分层状态的变化，春季浮游动物昼夜垂直迁移突然减少
DOI：
10.1016/j.jglr.2022.03.011
复制
发表时间：
2022
影响因子：
2.2
通讯作者：
Branstrator, Donn
中科院分区：
文献类型：
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作者：
Austin, Jay A.;Hrabik, Thomas R.;Branstrator, Donn
从2019年5月至7月部署在苏必利尔湖上级开放水域的声学多普勒海流剖面仪返回的信号强度测量结果用于估计水柱顶部50米的散射强度。它显示了一个强大的昼夜信号，在夜间更高的散射强度，符合正常的昼夜垂直迁移的浮游生物。然而，夜间散射信号的强度在6月10日突然下降，与冬季层结（冷水在温暖的水的顶部）和中性层结期的开始相一致。我们假设，浮游动物行为的突然变化是由于过渡后，在水柱深处的浮游植物的可用性，通过辐射驱动的对流混合整个水柱的时间尺度小时。
Returned signal strength intensity measurements from an acoustic Doppler current profiler deployed at an open-water site in Lake Superior from May-July 2019 were used to estimate the scattering intensity over the top 50 m of the water column. It displayed a strong diel signal, with higher scattering intensity at night, consistent with the normal diel vertical migration of planktonic organisms. However, the intensity of the nocturnal scattering signal decreased abruptly on 10 June, coincident with the end of winter stratification (cold water on top of warmer water) and the beginning of the neutrally stratified period. We hypothesize that the sudden change in zooplankton behavior is due the availability of phytoplankton deep in the water column after the transition, made possible by radiatively driven convection mixing the entire water column on time scales of hours.