Publication Date:
2024-07-19
Description:
In some parts of the Southern Ocean (SO), even though low surface concentrations of iron (Fe) and manganese (Mn) indicate FeMn co-limitation, we still lack an understanding on how Mn and Fe availability influences SO phytoplankton ecophysiology. Therefore, this study investigated the effects of Fe and Mn limitation alone as well as their combination on growth, photophysiology and particulate organic carbon production of the bloom-forming Antarctic diatom Chaetoceros debilis. Our results clearly show that growth, photochemical efficiency and carbon production of C. debilis were co-limited by Fe and Mn as highest values were only reached when both nutrients were provided. Even though Mn-deficient cells had higher photochemical efficiencies than Fe-limited ones, they, however, displayed similar low growth and POC production rates, indicating that Mn limitation alone drastically impeded the cell's performance. These results demonstrate that similar to low Fe concentrations, low Mn availability inhibits growth and carbon production of C. debilis. As a result from different species-specific trace metal requirements, SO phytoplankton species distribution and productivity may therefore not solely depend on the input of Fe alone, but also critically on Mn acting together as important drivers of SO phytoplankton ecology and biogeochemistry.
Keywords:
Carbon, organic, particulate, per cell; Carbon, organic, particulate, production per cell; Carbon/Nitrogen ratio; Carbon/Nitrogen ratio, standard deviation; co-limitation; Diatom; Electron transport rate, absolute; Electron transport rate, absolute, standard deviation; Fe; Functional absorption cross sections of photosystem II reaction centers; Functional absorption cross sections of photosystem II reaction centers, standard deviation; growth; Growth rate, standard deviation; Irradiance; Maximum photochemical quantum yield of photosystem II; Maximum photochemical quantum yield of photosystem II, standard deviation; Mn; Particulate organic carbon, production, standard deviation; Particulate organic carbon content per cell, standard deviation; Photosynthesis; Phytoplankton growth rate; Species; trace metals; Treatment; Type
Type:
dataset
Format:
text/tab-separated-values, 234 data points