Temperature effects on carbon mineralization of sinking copepod carcasses

Publikation: Bidrag til tidsskriftTidsskriftartikelForskningpeer review

6 Downloads (Pure)

Abstrakt

Copepod carcasses are prevalent in marine ecosystems and might represent an important component of the sinking flux of particulate organic carbon in the ocean. The extent to which copepod carcasses contribute to the biological carbon pump is controlled by different environmental factors, including temperature. However, the effect of temperature on the longer-term kinetics of carbon mineralization of copepod carcasses is not well-studied. We conducted laboratory experiments to quantify the carbon mineralization associated with sinking carcasses of the cosmopolitan copepod Acartia tonsa through aerobic microbial respiration at 5 temperatures (20, 16, 12, 8, and 4 degrees C). Microbial respiration rates associated with the carcasses were positively correlated with temperature and characterized by an initial short lag-phase, a rapid increase to a maximum rate, and a subsequent gradual decline in the rate of degradation. On average, 50-12 d at 20 degrees C, versus >60 d at 4 degrees C. During the incubations, most carbon mineralization occurred in the ambient seawater, likely fueled by dissolved organic carbon leaking from the carcasses into the surrounding seawater. Extrapolating measured carbon turnover and sinking rates suggests that at 20 degrees C, the mineralization of sinking copepod carcasses is constrained to the surface ocean. In contrast, at 4 degrees C, sinking copepod carcasses can reach the deep ocean before they have been completely degraded. Hence, in low-temperature regions, copepod carcasses may represent an important agent for carbon export through the biological carbon pump.
OriginalsprogEngelsk
TidsskriftMarine Ecology Progress Series
Vol/bind679
Sider (fra-til)31-45
ISSN0171-8630
DOI
StatusUdgivet - 25. nov. 2021

Fingeraftryk

Dyk ned i forskningsemnerne om 'Temperature effects on carbon mineralization of sinking copepod carcasses'. Sammen danner de et unikt fingeraftryk.

Citationsformater