Tidal Exchange
Blue Carbon
Integrating Restoration & Research
Gaze across the slough’s tidal wetlands and you will see lush habitat and amazing wildlife — harbor seals hauled out on muddy shores, shorebirds probing the mud for a wriggly meal, and Southern sea otters grooming their fur as they rest on pickleweed. Land managers and conservation scientists at Elkhorn Slough are dedicated to conserving the richness, beauty, and productivity of this vital ecosystem. As part of the Reserve’s mission to study and protect these natural wonders, these researchers are working to monitor and restore a valuable, yet easily overlooked, resource linked inextricably to the health of the slough’s salt marshes — blue carbon. Blue carbon refers to carbon dioxide (CO2) removed from the atmosphere by coastal or marine ecosystems. Tidal marshes are especially effective “carbon sinks” (systems that capture and store atmospheric CO2) because, as sea level rises, the marshes’ capacity to sequester carbon does, too. Salt marshes occupy a very specific elevation relative to the tides—submerged too little, they dry out; too much, they drown. To remain in this ideal zone, marsh plants
(Cover) ESNERR Stewardship Coordinator Andrea Woolfolk in healthy salt marsh that serves as a reference site for the Tidal Marsh Restoration Project; (inset) ESNERR Research Coordinator Kerstin Wasson measures greenhouse gas emitted by pickleweed at the restoration site.
gradually grow to follow changes in sea level, burying past generations of vegetation and sediment along with captured carbon. Salty, low-oxygen conditions beneath the surface preserve these buried sediments indefinitely, limiting the release of potent greenhouse gases (such as methane and nitrous oxide) that contribute even more significantly to climate change than CO2. Recent studies indicate that salt marshes are able to trap and store 10–15 times more atmospheric carbon than temperate forests, reaffirming that these tidal wetlands are critically important to restore and protect. Continued on page 4
TE Summer 2015 FINAL.indd 1
8/19/15 5:54 PM