Acoustical Sensing of Small-Scale Vertical Structures in Zooplankton Assemblages
Acoustical Sensing of Small-Scale Vertical Structures in Zooplankton Assemblages
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DOI：
10.5670/oceanog.1998.10
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发表时间：
1998
期刊：
影响因子：
2.8
通讯作者：
D. Holliday;Pieper;Greenlaw;Dawson
中科院分区：
文献类型：
--
作者：
D. Holliday;Pieper;Greenlaw;Dawson
在自然环境中观察水生动物仍然是生物海洋学和湖沼学的主要挑战。小型浮游动物的摄食、繁殖、生长和捕食的关键过程发生在从几毫米到与个体范围相匹配的尺度上。在实验室中再现海洋环境的所有基本特征往往是困难的，因为在实验室中观察小规模的过程比在海上更容易。因此，不断提高我们的能力，观察和量化的空间和时间变化的浮游动物的分布和丰富的自然物理，化学和其他生物领域的兴趣。精确测量空间分布是困难的。传统的CTD组件、荧光计和声学传感器，当在船上以“投射”模式使用时，往往具有-1米的垂直分辨率。与“下降”率有关的测量所需的时间、通过某些类型的传感器抽水的必要性、在准随机的、统计上非平稳的局部环境中获取和平均多个样本的必要性以及船舶运动与传感器的耦合都有助于数据中的“涂抹”空间模式。这些实际问题往往会降低在海上获得的测量的空间分辨率。在我们对浮游生物的许多声场研究中，海洋条件和随之而来的深度不均匀取样使我们，
OBSERVATION OF AQUATIC animals in their natural environments remains a major challenge in both biological oceanography and limnology. Critical processes in feeding, reproduction, growth, and predation in small zooplankton occur at scales from fractions of millimeters up to scales that match the ambits of individuals. It is often difficult to reproduce all essential features of the marine environment in the lab, where observation of smallscale processes is more tractable than at sea. Therefore there is continuing interest in improving our ability to observe and quantify in situ spatial and temporal changes in the distribution and abundance of zooplankton in relation to natural physical, chemical, and other biological fields. Making accurate measurements of spatial distributions is difficult. Conventional CTD packages, fluorometers, and acoustical sensors, when used in a "cast" mode from a ship, tend to have -1 m vertical resolutions. The time it takes to make a measurement in relation to the "'drop" rate, the necessity to pump water through some kinds of sensors, the need to acquire and average multiple samples in a quasi-random, statistically nonstationary local environment, and the coupling of the motions of the ship to the sensor all contribute to "smearing" spatial pattern in the data. These practical issues tend to reduce the spatial resolution of measurements one obtains at sea. In many of our acoustical field studies of plankton, sea conditions and consequent uneven sampling in depth caused us, in