基于声学方法的南黄海浮游动物垂直迁移季节变化研究

Seasonal variation of the zooplankton vertical migration in the southern Yellow Sea described by acoustic method

为研究南黄海浮游动物垂直迁移的季节变化,分析了2006年至2007年4个季节布放潜标中声学测流仪的观测数据。结果是:声学测流仪测量的后向散射强度呈现显著的日变化特征,这是由浮游动物垂直迁移造成的;在4个季节中都出现这一凌晨向下、黄昏向上的垂直迁移,但是垂直迁移发生的时间有季节变化。利用南黄海辐射通量的直接观测数据,讨论了垂直迁移发生时间与光照的关系,结果表明垂直迁移的季节变化主要受光照的影响。这对于研究浮游动物垂直迁移机制有一定意义。

Data from acoustic current profiler deployed as mooring in four seasons are analyzed to study seasonal variation of the zooplankton vertical migration in the southern Yellow Sea. Volume backscattering strength measured with acoustic current profiler has dominant diel variation, which results from vertical migration of zooplankton The vertical migration （downward at dawn and upward at dusk） occurs in all four seasons. However, the occurrence time of the vertical migration shows seasonal variation. The relationship between the migration occurrence time and the daylight is discussed based on the direct observation of radiative flux. It shows that the seasonal variation of the migration occurrence time is mainly affected by the daylight. All these are important for characterization of zoo- plankton vertical migration mechanism.