British Antarctic Survey, Natural Environment Research Council, Cambridge, CB3 0ET, UK.
Nat Commun. 2020 Nov 27;11(1):6051. doi: 10.1038/s41467-020-19956-7.
Antarctic krill play an important role in biogeochemical cycles and can potentially generate high-particulate organic carbon (POC) fluxes to the deep ocean. They also have an unusual trait of moulting continuously throughout their life-cycle. We determine the krill seasonal contribution to POC flux in terms of faecal pellets (FP), exuviae and carcasses from sediment trap samples collected in the Southern Ocean. We found that krill moulting generated an exuviae flux of similar order to that of FP, together accounting for 87% of an annual POC flux (22.8 g m y). Using an inverse modelling approach, we determined the krill population size necessary to generate this flux peaked at 261 g m. This study shows the important role of krill exuviae as a vector for POC flux. Since krill moulting cycle depends on temperature, our results highlight the sensitivity of POC flux to rapid regional environmental change.
南极磷虾在生物地球化学循环中扮演着重要的角色，它们有可能向深海输送高颗粒有机碳（POC）通量。它们在生命周期中还具有持续蜕皮的特殊习性。我们通过收集南大洋沉积物捕获器样本中的粪粒（FP）、蜕皮和尸体来确定磷虾对 POC 通量的季节性贡献。我们发现，磷虾蜕皮产生的蜕皮通量与 FP 相似，两者共占年 POC 通量（22.8 g m y）的 87%。通过一种反演模型方法，我们确定了产生这种通量所需的磷虾种群大小峰值为 261 g m。本研究表明磷虾蜕皮是 POC 通量的重要载体。由于磷虾蜕皮周期取决于温度，我们的结果强调了 POC 通量对快速区域环境变化的敏感性。
