Mesozooplankton community respiration and its relation to particle flux in the oligotrophic eastern Mediterranean

Abstract

Organic carbon flux and zooplankton carbon consumption rates were measured in the deep water of the eastern Mediterranean. Standardized carbon consumption rates of zooplankton were higher than rates measured in the deep open ocean, probably due to the elevated temperature of ∼14°C in the bathypelagic zone of the eastern Mediterranean. The absolute rates, however, were very low, reflecting the oligotrophic character of the basin. Zooplankton were estimated to consume 23% of the sinking flux between 1050 m and 4250 m. Owing to the high temperature in the Levantine deep-sea, however, the carbon losses from the sinking flux calculated by the Martin equation are probably underestimated, and higher total losses may occur. Lucicutia longiserrata, an intrinsic faunal element in the deep Levantine Sea, played a significant role in carbon recycling. The increased recycling efficiency of pelagic organisms in the bathypelagic zone possibly facilitates starvation of the benthos in the nutrient-poor Levantine Basin. Copyright 2004 by the American Geophysical Union.