Environment & Ecology · Environment

With reference to coastal 'Blue Carbon' ecosystems such as mangroves, salt marshes and seagrass meadows, consider the following statements: I. A significant proportion of oceanic sediment carbon is associated with coastal vegetated ecosystems. II. On a per-hectare basis, these ecosystems can sequester substantially more carbon than most terrestrial tropical forests. III. The bulk of the carbon stored in such ecosystems is retained within the soil and sediment layers rather than in above-ground biomass. Which of the statements given above are correct?