Study of Phytoplankton Biomass and Environmental Drivers in and around the Ross Sea Marine Protected Area

The Southern Ocean plays a vital role in the global climate system and the life cycle of high-latitude marine life. Phytoplankton is an important source of primary productivity in this ecosystem. Its future changes could affect Southern Ocean geochemistry, carbon export, and higher trophic organisms. To better protect Antarctica, three different marine protected areas (MPA) have been established in the Ross Sea region. Because time-continuous and regionally complete data are difficult to obtain in this region, we obtained data from ocean model outputs to understand the spatiotemporal variability of phytoplankton biomass in this region. This study explored the correlation between phytoplankton biomass and key environmental factors. Phytoplankton biomass peaks in February as temperatures rise and sea ice melts. Correlations also vary between different protected areas. The correlation between biomass, nitrate, and salinity in the Krill Research Zone (KRZ) area was significantly different from other protected areas. In addition, in the context of global warming, Antarctica lacks temperature perception. The model results show a downward trend in temperature and an increase in sea ice coverage in the western Ross Sea that other studies have also pointed to. How phytoplankton biomass will change in protected areas in the future is a question worth considering. Finally, the study simply simulates future regional trends by comparing the biomass distribution in hot years to average years. This will increase our knowledge of the polar system.

Automated summary

The Southern Ocean's role in the global climate system and high-latitude marine life is crucial. Phytoplankton serves as a significant source of primary productivity in this ecosystem. Understanding the temporal and spatial variations of phytoplankton biomass in the Southern Ocean is challenging due to limited data availability. In this study, ocean model outputs were used to examine the relationship between phytoplankton biomass and environmental factors in protected areas of the Ross Sea region. The results show variations in biomass and correlations with temperature, sea ice, and nutrient levels, highlighting the importance of considering future changes in phytoplankton biomass within these protected areas.