Vådområde: Forskelle mellem versioner
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I et vådområde ligger vandspejlet normalt lige under jordoverfladen. I perioder med [[nedbør]] hæves vandspejlet eventuelt og området oversvømmes.<ref>Webarchive backup: [http://web.archive.org/web/20070927180739/www.ra.dk/sw2022.asp Roskilde Amt, Vandmiljøplan II: Hvad er et vådområde?]</ref>
Man har opdaget at vådområder har oplagret store mængder kulstof ({{chem|C}}) og fortsat er netto optagere i [[Kulstofkredsløb|jordklodens globale kulstofkredsløb]], sålænge de er under vand. [[Kuldioxid]] ({{chem|CO|2}}) trækkes ud af [[luft]]en via [[fotosyntese]] og bindes. Selv kunstigt anlagte vådområder oplagrer kulstof på denne måde. Kulstof kan være lagret i flere hundrede tusind år. Selvom man medregner vådområdernes udslip af [[metan]], er vådområder netto kulstof-optagere. Metan er en gas med den kemiske betegnelse {{chem|CH|4}} og
<ref>[http://www.sciencedaily.com/releases/2008/05/080507105549.htm Iowa State University (2008, May 8). Ponds Found To Take Up Carbon Like World's Oceans. ScienceDaily. Retrieved May 8, 2008] Citat: "..."Aquatic ecosystems play a disproportionately large role in the global carbon budget," Downing said...The combined effect is that farm ponds could be burying as much carbon as the world's oceans, each year...It may be that ponds will be the modern equivalent of the swamps that formed coal in the past. But before we all rush into making ponds to trap carbon we need to do some basic research here in the UK..."</ref>
<ref>[http://www.sciencedaily.com/releases/2013/06/130620132116.htm American Society of Agronomy (ASA), Crop Science Society of America (CSSA) (2013, June 20). Farming carbon: Study reveals potent carbon-storage potential of human-made wetlands. ScienceDaily] Citat: "...Once carbon ends up in wetland soil, it can also remain there for hundreds to thousands of years because of water-logged conditions that inhibit microbial decomposition...But in a new analysis that modeled carbon fluxes over 100 years from the two constructed Ohio marshes and 19 other wetlands worldwide, Mitsch, Bernal, and others demonstrated that most wetlands are net carbon sinks, even when methane emissions are factored in..."</ref>
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