Phytoplankton lysis predicts dissolved organic carbon release in marine plankton communities

[摘要] The relationship between the percent extracellular carbon release (PER) andthe specific lysis rates of phytoplankton was examined across a range ofcommunities spanning from highly oligotrophic ones in the subtropicalAtlantic Ocean to productive ones in the N. African upwelling and theSouthern Ocean. Communities in oligotrophic waters supported highphytoplankton cell lysis rates and low particulate primary production ratesbut high dissolved primary production and PER. The percent extracellularcarbon released increased with increasing lysis rates to reach an asymptoteat about 80% PER with specific lysis rates > 1.5 d⁻¹,observed in the most oligotrophic conditions tested. These results confirmthat high phytoplankton mortality in the oligotrophic ocean leads to highPER, accounting for the large fraction of the photosynthetic carbonchannelled through bacteria characteristic of oligotrophic marinecommunities.

[学科分类] 地球化学与岩石