Chromogenic CompoundsNitrogen FixationNitrogen CompoundsNitrogen IsotopesNitrogen CycleBlood Urea NitrogenNitrogen DioxideReactive Nitrogen SpeciesNitrogen OxidesPII Nitrogen Regulatory ProteinsQuaternary Ammonium CompoundsMolecular StructureCarbonNitratesAmmoniaFertilizersSulfur CompoundsVolatile Organic Compounds