一、概论 型 (一)氨的来源 6 reduction by some anaerobic bacteria. most plants Amino acids and other reduced synthesis in nitrogen-carbon plants and compounds microorganisms degradation by animals and microorganisms Nitrate Ammonia NO3 3 NH denitrification nitrogen fixation by some bacteria (e.g.,Klebsiella Azotobacter,Rhizobium) nitrification nitrification by soil bacteria by soil bacteria e.g..Nitrobacter) Nitrite (e.g.,Nitrosomonas) NO2一、概论 （一）氨的来源