Carbon budget in the black

摘要

A significant fraction of a common organic component of marine sediments has an unexpected source, providing a fresh context for studies of the global carbon cycle in oceanic and terrestrial settings. The global carbon cycle is both a consequence anda determinant of the state of the planet. Not surprisingly, then, a small army of scientists is at work studying the exchange of various guises of the element between land, atmosphere and ocean. One of those guises is 'black carbon', a relatively inertform that is produced by incomplete combustion during wildfiresor the industrial burning of fossil fuels. It initially accumulates in soils, and is then distributed to lake and river sediments, and eventually to marine sediments.