Seaweed
"Seaweed" is a colloquial term and lacks a formal definition. A seaweed may belong to one of several groups of multicellular algae: the red algae, green algae, and brown algae. As these three groups do not have a common multicellular ancestor, the seaweed are in a polyphyletic group. In addition, some tuft-forming bluegreen algae (Cyanobacteria) are sometimes considered to be seaweed.
Ocean storage of carbon dioxide
In order to mitigate global warming, seaweed farming is both a possible and plausible way. This method was adopted in early ocean algae proposals to mitigate global warming. This is done through commercial kelp farms designed to take up tens of thousands of square kilometres of the open ocean. Through this method, seaweed beds will perform as an effective sinks by decreasing the level of dissolved inorganic carbon (DIC) in the ocean.
Seaweeds do the above by removing carbon through the process of photosynthesis, taking in excess CO2 and producing O2. Facts and figures have shown that 0.7 million tonnes of carbon are removed from the sea each year by commercially harvested seaweeds. Even though seaweed biomass is small as compared to the coastal region. They remain essential due to their biotic components, the ability to provide valuable ecosystem services and high primary productivity. Seaweeds are different from mangroves and seagrasses, they are photosynthetic algal organisms and non-flowering. Even so, they are primary producers that grows in the same way as their terrestrial counterparts, both of which assimilate carbon by the process of photosynthesis and generates new biomass by taking up phosphorus, nitrogen, and other minerals.