Atmospheric Nz 3800000 Biological Industrial Combustion Biolo fixation fixation Lightning fixation fixation Lightning 0.004/year 0. 14/year, 0.036/year 0.004/year 0. 10/ear Land Oceans Plants Plants 12 02 03 Dead organic Dead organic 9。os 300 550 Ammonification Ammonification Nitrification Nitrification NH Inorganic 0.008 year 0.005year Inorganic 16 577 Rivers sedimentation Sediments 400.000 0.00025/ year NHa The Global Nitrogen Cycles Rock 190.00,0 0.002/year Organic NThe Global Nitrogen Cycles