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Building Blue Carbon Projects
An Introductory Guide
damage and erosion, and diminish flooding by holding excess storm waters. Their presence also
aids in regulating water levels during periods of dry weather.
Seagrass Meadows
Seagrasses are fully submerged flowering plants that can grow in meadows and are found in the
near-shore coastal areas of all continents except Antarctica. Seagrass roots accumulate vertically
beneath the seafloor over time, creating a significant store of buried carbon. It is estimated that a
hectare of seagrass meadow, even with its small living biomass, may hold as much carbon as one
to two hectares of temperate forest (Murray
et al.
, 2011). Of the three coastal ecosystems key to
Blue Carbon, seagrasses are currently the least well-studied and thus present an area for
significant exploration and knowledge expansion.
Similar to mangrove forests and saltwater marshes, seagrass meadows provide important
ecosystem services such as habitat for many species of fish and invertebrates. They also provide
water filtration services, by holding nutrients and sediment in their grassy biomass. Recently it has
been suggested that seagrass restoration projects could effectively mitigate climate change while
providing returns at least equal to the initial project investment needed, assuming an appropriate
carbon tax was in place (Duarte
et al
., 2013).
Coastal Blue Carbon ecosystems include mangrove forests, seagrass meadows and saltwater marshes (image credit
from left to right: Florida Keys mangroves - Riandi/Wikimedia Commons; Belize seageass meadow - Steven J Lutz,
GRID-Arendal; Carpinteria Salt Marsh Reserve - Gerick Bergsma/Marine Photobank).
