Consequences of the cultivation of energy crops for the global nitrogen cycle.
In this paper, we assess the global consequences of implementing first- and second-generation bioenergy in the coming five decades, focusing on the nitrogen cycle. We use a climate mitigation scenario from the Organization for Economic Cooperation and Development's (OECD) Environmental Outlook, in which a carbon tax is introduced to stimulate production of biofuels from energy crops. In this scenario, the area of energy crops will increase from 8 Mha in the year 2000 to 270 Mha (14% of total cropland) and producing 5.6 Pg dry matter per year (12% of energy use) in 2050. This production requires an additional annual 19 Tg of N fertilizer in 2050 (15% of total), and this causes a global emission of 0.7 Tg of N2O-N (8% of agricultural emissions), 0.2 Tg NO-N (6%), and 2.2 Tg of NH3-N (5%). In addition, we project that 2.6 Tg of NO3(-)-N will leach from fields under energy crops. The emissions of N2O may be an important term in the greenhouse gas balance of biofuels produced from energy crops.
Bouwman
A F
AF
Netherlands Environmental Assessment Agency (PBL), P.O. Box 303, 3720 AH, Bilthoven, The Netherlands. lex.bouwman@pbl.nl
Van Grinsven
J J M
JJ
Eickhout
B
B
D056804:Biofuels; D018556:Crops, Agricultural / Q000378:metabolism*; D004777:Environment; D005308:Fertilizers; D009584:Nitrogen / Q000737:chemistry / Q000378:metabolism*; D009586:Nitrogen Fixation; D009609:Nitrous Oxide; D013997:Time Factors
D056804:Biofuels; D005308:Fertilizers; D009609:Nitrous Oxide; D009584:Nitrogen