Legumes - INTA

• 33 - 46 Gt N is annually fixed by legumes
• 10 g more CO2 are respired for every gram N
assimilated cf. to if the plant has used fertilizer or soil N
instead
• 350-500 Gt of additional CO2 is therefore respired from
legume roots each year as a result of fixation
• 300 Gt CO2 is emitted annually from the manufacture of
100 Gt fertilizer N
Swedish University of Agricultural Sciences
www.slu.se