here, a good ms

http://www.academia.edu/4129772/Using_marine_macroalgae_for_carbon_sequestration_a_critical_appraisal

blue carbon - Water accumulate carbon by sea, lake, or any kinds of reservoir.

Another paper, not mainly dealing with using macroalgae for sequestration, but with the occurence of anomalous macroalgal blooms (mainly ulva and sargassum) driven ultimately by eutrophication came out yesterday:

Green and golden seaweed tides on the rise. Nature 504, 84–88 (05 December 2013), Victor Smetacek and Adriana Zingone

http://www.nature.com/nature/journal/v504/n7478/full/nature12860.html

In it, the authors also suggest that harvesting these blooms may be useful, but probably not so much for carbon sequestration, but rather for using them as a valuable resource. But they also warn "Needless to say, harvesting floating macroalgae is the logical and ultimate step in the process known as ‘fishing down marine food webs'". They also point to the fact that we don't really understand yet, why and when these blooms occur.

Personally I don't think that macroalgae can be a big contributor to carbon sequestration, since of the ~50 Pg C/yr net primary production (NPP) in the ocean, only about 1 Pg C/yr is by macroalgae (citations for that in the paper contributed by Loretto; thank you, Loretto for that hint). The potential for increased NPP is probably limited in coastal systems that are already under heavy pressure. That limits sequestration efforts to macroalgal species that have no requirement for a hard substrate to sit on, such as free-floatig sargassum.

One of the papers I recently noticed dealing with this topic was "The value of blue carbon sequestration and storage in coastal habitats" published in Estuarine, Coastal and Shelf Science. As such I have not come across any paper which has provided a detailed overview of the status of researches going on throughout the world related to "blue carbon". Mostly, the papers provide a regional assessment of carbon sequestration by mangroves, marshes and seagrasses.

Thanks Loreto, Chris and Mohit

Some interesting blue carbon research being conducted in North America looking at carbon capture/storage/sequestration in salt marshes by scientists from McGill University in Canada and the United States Geological Survey.

Some papers below:

Also:

Thanks a lot Jeff, these are very interesting articles.