A carbon sink, natural or artificial, is an entity that removes (sequesters) more carbon from the atmosphere than it releases. Also known as carbon pools, the most important natural carbon sinks are soils, plants (vegetation), and oceans. In the past two hundred years, human processes such as deforestation and industrial agriculture have significantly degraded or destroyed natural carbon sinks, causing the release of carbon (greenhouse gasses or emissions) which is linked to climate change. Understanding natural carbon sinks is key in the fight against climate change.