The role of deep-sea zooplankton in carbon cycles

Abstract

Zooplankton in the deep sea and benthic boundary layer are involved in the processes of carbon utilization, particle repackaging, and direct transport of carbon in their bodies. This paper summarizes previous work on deep-sea zooplankton carbon utilization, presents new data on deep-sea zooplankton feeding rates in relation to various environmental parameters, and discusses unique perspectives on deep-sea zooplankton food webs gained from gut contents analysis relative to available particles in the water column. In situ deep-sea near-bottom zooplankton feeding rates, measured with an alginate-microsphere tracer bead technique, were more closely related to ambient particulate organic carbon than to depth, temperature, or oxygen at five sites from 740-3000 m in two geographic locations (Santa Catalina Basin in the California Borderland, Volcano 7 seamount in the Eastern Tropical Pacific). Differences in copepod gut contents between the 1300 m sites in the two geographic locations included less algal material in the Santa Catalina Basin animals and the presence of abundant bacteria like bodies (suggesting ingestion of bacterial aggregates) in the seamount copepods. -from Authors