Carbon sequestration in croplands: the potential in Europe and the global context

Abstract

Biospheric carbon sinks and sources can be included in attempts to meet emission reduction targets during the first commitment period of the Kyoto Protocol. Forest management, cropland management, grazing land management and re-vegetation are allowable activities under Article 3.4 of the Kyoto Protocol. Soil carbon sinks (and sources) can, therefore, be included under these activities. In this paper, the role of croplands in the European carbon budget and the potential for carbon sequestration in European croplands are reviewed. The global context is then considered. Croplands are estimated to be the largest biospheric source of carbon lost to the atmosphere in Europe each year, but the cropland estimate is the most uncertain among all land-use types. It is estimated that European croplands (for Europe as far east as the Urals) lose 300 Mt C per year. The mean figure for the European Union is estimated to be 78 (S.D. 37) Mt C per year. There is significant potential within Europe to decrease the flux of carbon to the atmosphere from cropland, and for cropland management to sequester soil carbon, relative to the amount of carbon stored in cropland soils at present. The biological potential for carbon storage in European (EU15) cropland is of the order of 90-120 Mt C per year with a range of options available including reduced and zero tillage, set-aside, perennial crops and deep rooting crops, more efficient use of organic amendments (animal manure, sewage sludge, cereal straw…