Phil Colarusso, Boston Office of the EPA
Wetlands and coastal waters are exceptionally effective at storing carbon as well as performing many other ecosystem functions. Phil Colarusso tells us how cities and the global climate benefit from offshore seagrass beds, one of the richest of ecological resources and carbon sinks and part of the Boston area's native habitat. Eelgrass survival is entirely dependent on effective management of water resources for human use, especially intact healthy wetlands and efficient sewage disposal.
Presented at the Urban and Suburban Carbon Farming to Reverse Global Warming conference at Harvard University on May 3, 2015, organized by Biodiversity for a Livable Climate.
www.bio4climate.org
2. Blue Carbon
Carbon that is associated with salt marsh, seagrass or
mangroves
Species in these groups have high growth rates and
thus can absorb large quantities of CO2
Carbon is sequestered in the sediments/soil for as long
as the habitat stays intact
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7. Annual Carbon Sequestration Rates
Mangroves: 0.13 to 24 Mg CO2e/ha/yr
Salt Marsh: 0.01 to 63 Mg CO2e/ha/yr
Seagrass: -76 to 85 Mg CO2e/ha/yr
Tropical forests: -20.02 to 8 Mg CO2e/ha/yr
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9. Importance of Seagrass
Seagrass meadows are estimated to occupy less than
0.2% of the area of the world’s oceans, but account for
about 20% of the sequestered carbon on an annual
basis
10. Loss/degradation of Coastal
Wetlands
Mangroves
Globally losing 0.66%/yr
Greatest losses are in Asia
Salt Marsh
Data in many geographic areas is scarce
Globally estimated to be 1 to 2%/yr
Seagrass
Globally 1-3%/yr
11. Putting the losses in context
Emissions that result from conversion and degradation
of coastal wetlands estimated to be between 300 to
900 million tons CO2e
Roughly equivalent to the annual emissions from
energy and industry sectors for Poland and Germany
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15. Seagrass stressors
Reductions in water clarity/eutrophication
Piers/wharfs/moorings
Dredging
Invasive species
Trawling/shellfishing
16. What you can do
Reduce nitrogen
Cut fertilizer use
Eat lower on the food chain
Mass transit/increased fuel efficiency
Limit/reduce impervious surface
Avoid farmed shrimp
Be a responsible boater