Carbon footprints of crops from organic and conventional arable crop rotations - using a life cycle assessment approach

A method was suggested for allocating effects of fertility building crops in life cycle assessments. The results showed significantly lower carbon footprint of the crops from the 'Biogas' rotation (assuming that biogas replaces fossil gas) whereas the remaining crop rotations had comparable carbon footprints per kg cash crop. The study showed considerable contributions caused by the green manure crop (grass-clover) and highlights the importance of analysing the whole crop rotation and including soil carbon changes when estimating carbon footprints of organic crops especially where green manure crops are included.