Will changes in soil organic carbon act as a positive or negative feedback on global warming?

  title={Will changes in soil organic carbon act as a positive or negative feedback on global warming?},
  author={Miko U. F. Kirschbaum},
The world's soils contain about 1500 Gt of organic carbon to a depth of 1m and a further 900 Gt from 1--2m. A change of total soil organic carbon by just 10% would thus be equivalent to all the anthropogenic CO2 emitted over 30 years. Warming is likely to increase both the rate of decomposition and net primary production (NPP), with a fraction of NPP forming new organic carbon. Evidence from various sources can be used to assess whether NPP or the rate of decomposition has the greater… 

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