Saltmarshes are coastal wetlands that are flooded and drained by salt water brought in by the tides. The soil may be composed of deep mud and peat. Because saltmarshes are frequently submerged by the tides and contain a lot of decomposing plant material, oxygen levels in the peat can be extremely low. Salt marshes occur worldwide, particularly in middle to high latitudes. Thriving along protected shorelines, they are a common habitat in estuaries. These intertidal habitats are essential for healthy fisheries, coastlines, and communities.
Blue carbon is simply the term for carbon captured by the world's ocean and coastal ecosystems. Sea grasses, mangroves, and saltmarshes along our coast "capture and hold" carbon, acting as a carbon sink. These coastal systems, though much smaller in size than the planet's forests, sequester this carbon at a much faster rate, and can continue to do so for millions of years. Most of the carbon taken up by these ecosystems is stored below ground. The carbon found in coastal soil is often thousands of years old.
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