Quantifying Active Carbon Flux from Euphausiid Respiration in the Clarion-Clipperton Zone

Abstract

The process of moving carbon from the atmosphere into the ocean is called carbon flux. Within the oceans, carbon flux has two main components: active flux and passive flux. Passive flux considers only the sinking of non-living matter such as detritus and waste. Active flux is the movement of carbon to depth through respiration of animals during vertical migration. The Clarion Clipperton mining zone falls directly below an oxygen minimum zone (OMZ). During euphausiid diel vertical migration, their metabolism burns the carbon from phytoplankton consumed at the surface, then they respire carbon dioxide. This process contributes to active carbon flux. Euphausiid carbon flux has been measured only a few times in the central Pacific and no research has been done within an OMZ. Euphausiid respiration has an almost negligible effect on total carbon flux with 0 - 0.0748 (mg C/day/m2) which is less than 1% of passive flux in the testing area, however, there is still respiratory flux occurring. The majority of carbon flux in this area comes from passive flux and respiratory flux from other migrating organisms. This is a valuable study to estimate active carbon flux of euphausiids within an OMZ, and this study provides important baseline observations before deep sea mining begins. More research is needed on respiratory flux of other organisms to create a full representation of active carbon flux within this OMZ.