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StillnessClimate ecology fact

Mangroves, salt marshes and seagrass meadows draw carbon dioxide from the air and lock it away in waterlogged coastal mud, often for centuries. Scientists call this stored carbon 'blue carbon'.

Mangrove blue carbon

OceanClimateNatureBiologyScience

The story behind the card

The term was popularised by a 2009 United Nations report. Coastal mud holds so little oxygen that dead roots and leaves rot very slowly, so carbon keeps building up in the soil instead of returning to the air. These habitats cover only a small fraction of the seabed, yet they are thought to account for about half of all the carbon buried in ocean sediments. Mangroves also break waves, trap sediment and shelter young fish and crabs among their roots. When the wetlands are drained or cleared for shrimp farms or building, the stored carbon can escape back into the atmosphere.

Türkçe oku
Mangrovlar, tuz bataklıkları ve deniz çayırları havadaki karbondioksiti alır ve kıyıdaki suya doymuş çamura, çoğu zaman yüzyıllarca kalacak biçimde gömer. Bilim insanları bu şekilde depolanan karbona “mavi karbon” der.

Terim, 2009'da yayımlanan bir Birleşmiş Milletler raporuyla yaygınlaştı. Kıyı çamurunda oksijen o kadar azdır ki ölü kökler ve yapraklar çok yavaş çürür; böylece karbon havaya dönmez, toprakta birikmeye devam eder. Bu ortamlar deniz tabanının küçük bir bölümünü kaplar, ama okyanus tortullarına gömülen karbonun yaklaşık yarısının buralarda biriktiği düşünülüyor. Mangrovlar ayrıca dalgaları kırar, tortuyu tutar, köklerinin arasında yavru balıklara ve yengeçlere sığınak olur. Bu sulak alanlar karides çiftlikleri ya da yapılaşma için kurutulur veya temizlenirse, içlerinde saklanan karbon yeniden atmosfere karışabilir.

Sources and further reading

Background reading: Blue carbon
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