The Consumption of Marine Snow by Macrozooplankton and Its Impact on Aggregate Abundance In Situ

浮游动物对海洋雪（碎屑聚集体0.5 mm）的消耗有可能成为改变海洋中大沉降颗粒的粒度分布和丰度的最重要途径之一，并被假设为混合层以下颗粒通量随深度呈指数下降的主要原因。然而，人们对远洋动物食用浮游生物的能力几乎一无所知。我们建议调查两个潜在的最重要的大型浮游动物消费者的海洋雪，磷虾和doliolids。野外观察和我们实验室的初步实验清楚地表明，这些动物贪婪地消耗海洋雪。我们建议：1）量化太平洋磷虾（Euphausia pacifica）和Dolioetta gegenbauri对海洋雪的消耗，作为所提供的聚集体的大小，类型和质量，动物的大小和饥饿状态，以及替代悬浮食物来源的可用性的函数，和2）评估聚集体消耗大型浮游动物，特别是垂直迁移的磷虾的影响，对沿岸表层海水中海洋雪的丰度和垂直分布的影响。

Consumption of maarine snow (detrital aggregates0.5 mm) by zooplankton has the potential to be one of the mosst significnt pathways altering the size distribution and abundance of large sinking particales in the ocean and has been hypothesized to be a major cause of the exponential decrease in particulate flux with depth below the mixed layer. Yet almost nothing is known about the ability of pelagic animals to consume lare aggregates. We propose investigations of two of the potentially most important macrozooplankton consumers of marine snow, euphausiids and doliolids. Field observaations and preliminary experiments in our laboratory cleary demonstrate that these animals voraciouslly consume marine snow. We propose to 1) quantify the consumption of marine snow by Euphausia pacifica and Doliioetta gegenbauri as a function of the size, type and quality of aggregates offered, the size and hunger state of the animals, and the avialbility of alternate suspeended food sources, and 2) assess the impact of aggregate-conssuming macrozooplankton, especially vertically migrating euphausids, on the aabundance and vertical distripbution of marine snow in coastal surface water.