Volcanic marine photosynthesis stimulated by volcanoes | Science

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Marine phytoplankton, a microscopic unicellular seaweed, is responsible for about half of photosynthesis on Earth (1) Photosynthesis, on land and at sea, maintains atmospheric oxygen and CO₂ levels, governing the livability of the planet. This oceanic photosynthesis (called primary production) relies on opposite physical oceanographic mechanisms. The vertical stability or buoyancy of the ocean surface layer maintains the photosynthetic biomass in the sun-irradiated euphotic zone, while vertical mixing or upwelling provides deep-sea nutrients, such as nitrogen, phosphorus and silicon, necessary for the growth of phytoplankton. On page 1040 of this issue, Wilson et al. (2) signal a mechanism until then unknown that enhances the primary production of organic matter off Hawaii. They found that the lava discharged into the ocean by the erupting Kīlauea volcano created a plume of increased nutrient concentrations, increased phytoplankton growth, increased plankton abundance and a change in the composition of the plant. plankton species. Each of these responses could change the local carbon cycle.