A smaller proportion of black carbon created during combustion
will remain in soil than have been estimated before. Contrary to previous
understanding, burying black carbon in the ground in order to restrain climate
change will not create a permanent carbon reserve. Instead, a part of black
carbon will dissolve from soil to rivers. The flux of dissolved black carbon
from the rivers to the ocean was estimated in a research article published in
Science on 19 April. The research was funded among others by the Academy of
Finland.
The burning of organic matter creates 40–250 million tons of
black carbon every year. Black carbon is formed through the incomplete
combustion of organic matter, e.g. in forest fires, slash-and-burn and
controlled burning of fields. The general assumption has been that black carbon
would remain in soil even for millions of years.