Net community production in the bottom of first-year sea ice over the Arctic spring bloom
The balance of photosynthesis and respiration by organisms like algae and bacteria determines whether sea ice is net heterotrophic or autotrophic. In turn this clarifies the influence of microbes on atmosphere-ice-ocean gas fluxes and their contribution to the trophic system. In this study we define...
Published in: | Geophysical Research Letters |
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Main Authors: | , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
2017
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Subjects: | |
Online Access: | https://hdl.handle.net/1983/9d8db0a8-0156-4f63-9719-013674170fec https://research-information.bris.ac.uk/en/publications/9d8db0a8-0156-4f63-9719-013674170fec https://doi.org/10.1002/2017GL074602 https://research-information.bris.ac.uk/ws/files/132726725/Campbell_et_al_2017_Geophysical_Research_Letters.pdf https://research-information.bris.ac.uk/ws/files/133105073/grl56330_sup_0001_GRL56330_Supp_edited.pdf http://www.scopus.com/inward/record.url?scp=85028989453&partnerID=8YFLogxK |
Summary: | The balance of photosynthesis and respiration by organisms like algae and bacteria determines whether sea ice is net heterotrophic or autotrophic. In turn this clarifies the influence of microbes on atmosphere-ice-ocean gas fluxes and their contribution to the trophic system. In this study we define two phases of the spring bloom based on bottom ice net community production and algal growth. Phase I was characterized by limited algal accumulation and low productivity, which at times resulted in net heterotrophy. Greater productivity in Phase II drove rapid algal accumulation that consistently produced net autotrophic conditions. The different phases were associated with seasonal shifts in light availability and species dominance. Results from this study demonstrate the importance of community respiration on spring productivity, as respiration rates can maintain a heterotrophic state independent of algal growth. This challenges previous assumptions of a fully autotrophic sea ice community during the ice-covered spring. |
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