Highlights
- Persistent CO2 differences influenced the natural communities in mesocosm encloser.
- CO2 enrichment supported higher Chl-a concentrations.
- Elevated pCO2 decreased the mortality of the total phytoplankton and dominant small-sized diatoms.
- Elevation of CO2 enhance small-sized diatom dominance by reducing mortality in coastal ecosystems.
Abstract
The rise of atmospheric pCO2 has created a number of problems for marine ecosystem. In this study, we initially quantified the effects of elevated pCO2 on the group-specific mortality of phytoplankton in a natural community based on the results of mesocosm experiments. Diatoms dominated the phytoplankton community, and the concentration of chlorophyll a was significantly higher in the high-pCO2 treatment than the low-pCO2 treatment. Phytoplankton mortality (percentage of dead cells) decreased during the exponential growth phase. Although the mortality of dinoflagellates did not differ significantly between the two pCO2 treatments, that of diatoms was lower in the high-pCO2 treatment. Small diatoms dominated the diatom community. Although the mortality of large diatoms did not differ significantly between the two treatments, that of small diatoms was lower in the high-pCO2 treatment. These results suggested that elevated pCO2 might enhance dominance by small diatoms and thereby change the community structure of coastal ecosystems.
Wang P., Laws E., Wang Y., Chen J., Song X., Huang R., Wang T., Yi X., Sun J., Guo X., Liu X., Gao K. & Huang B., 2022. Elevated pCO2 changes community structure and function by affecting phytoplankton group-specific mortality. Marine Pollution Bulletin 175: 113362. doi: 10.1016/j.marpolbul.2022.113362. Article (subscription required).
