Printable Nitrogen Cycle Interactive Nitrogen Cycle Nitrogen Text

Back to Intro Page OXIDATION STATES ORGANIC MATTER PLANT AND ANIMAL MESQUITE RHIZOBIUM ALFALFA SOYBEAN BLUE-GREEN ALGAE AZOTOBACTER CLOSTRIDIUM PLANT AND ANIMAL RESIDUES R-NH2 + ENERGY + CO2 R-NH2 + H2O R-OH + ENERGY + 2NH3 MATERIALS WITH N CONTENT < 1.5% (WHEAT STRAW) CONTENT > 1.5% (COW MANURE) MICROBIAL DECOMPOSITION HETEROTROPHIC AMINIZATION BACTERIA (pH>6.0) FUNGI (pH<6.0) AMMONIFICATION GLOBAL WARMING pH>7.0 2NH4+ + 2OH- FIXED ON EXCHANGE SITES +O2 Nitrosomonas 2NO2- + H2O + 4H+ IMMOBILIZATION NH3 AMMONIA -3 NH4+ AMMONIUM -3 N2 DIATOMIC N 0 N2O NITROUS OXIDE 1 NO NITRIC OXIDE 2 NO2- NITRITE 3 NO3- NITRATE 5 OXIDATION STATES ATMOSPHERE N2O NO N2 N2O2- NH3 SYMBIOTIC NON-SYMBIOTIC + O2 Nitrobacter FERTILIZATION LIGHTNING, RAINFALL N2 FIXATION DENITRIFICATION PLANT LOSS AMINO ACIDS NO3- POOL LEACHING AMMONIA VOLATILIZATION NITRIFICATION NH2OH Pseudomonas, Bacillus, Thiobacillus Denitrificans, and T. thioparus MINERALIZATION + NITRIFICATION NO2- MICROBIAL/PLANT SINK TEMP 50°F pH 7.0 ADDITIONS LOSSES OXIDATION REACTIONS REDUCTION REACTIONS HABER BOSCH 3H2 + N2 2NH3 (1200°C, 500 atm) Joanne LaRuffa Robert Mullen Wade Thomason Susan Mullins Shannon Taylor Heather Lees Department of Plant and Soil Sciences Oklahoma State University INDUSTRIAL FIXATION

Interactive Nitrogen Cycle Joanne LaRuffa Robert Mullen Wade Thomason Susan Mullins Shannon Taylor Heather Lees Department of Plant and Soil Sciences Oklahoma State University Atmosphere Industrial Processes Plant and Animal Residues Lightning, Rainfall N2 Fixation Fertilizer Volatilization Plant Loss R-NH2 + Energy + CO2 Organic Matter R-NH2 + H2O N2, N2O, NO Plant/Microbial Sink R-OH + Energy + 2NH3 NO3- Pool 2NH4+ + 2OH- 2NH4+ + 2OH- Soil exchange sites Leaching Back to Intro Page 2NO2- + H2O + 4H+

Interactive Nitrogen Cycle Joanne LaRuffa Robert Mullen Wade Thomason Susan Mullins Shannon Taylor Heather Lees Department of Plant and Soil Sciences Oklahoma State University Atmosphere Industrial Processes Plant and Animal Residues Lightning, Rainfall N2 Fixation Symbiotic Rhizobium Alfalfa Mesquite Soybean Non-Symbiotic Azotobacter Cyanobacteria Clostridium Fertilizer Volatilization Plant Loss Via Decay Organic Matter N2, N2O, NO Plant/Microbial Sink NO3- Pool Back to Main Cycle Leaching Back to Intro Page

Interactive Nitrogen Cycle Joanne LaRuffa Robert Mullen Wade Thomason Susan Mullins Shannon Taylor Heather Lees Department of Plant and Soil Sciences Oklahoma State University Atmosphere Industrial Processes Plant and Animal Residues Lightning, Rainfall N2 Fixation Haber-Bosch (1200C, 500 ATM) 3CH4 + 3O2 + 2N2  4NH3 + 3CO2 Fertilizer Volatilization Plant Loss Organic Matter N2, N2O, NO Plant/Microbial Sink NO3- Pool Back to Main Cycle Leaching Back to Intro Page

Interactive Nitrogen Cycle Joanne LaRuffa Robert Mullen Wade Thomason Susan Mullins Shannon Taylor Heather Lees Department of Plant and Soil Sciences Oklahoma State University Atmosphere Industrial Processes Plant and Animal Residues Lightning, Rainfall N2 Fixation Fertilizer Small Percentage Soil Exchange Sites Plant/Microbial Sink Volatilization Plant Loss Organic Matter N2, N2O, NO NO3- Pool Back to Main Cycle Leaching Back to Intro Page

Interactive Nitrogen Cycle Joanne LaRuffa Robert Mullen Wade Thomason Susan Mullins Shannon Taylor Heather Lees Department of Plant and Soil Sciences Oklahoma State University Atmosphere Industrial Processes Plant and Animal Residues Lightning, Rainfall N2 Fixation Oxidation of N N2 + 3O2  2NO3- Fertilizer Volatilization Plant Loss Organic Matter N2, N2O, NO Plant/Microbial Sink NO3- Pool Back to Main Cycle Leaching Back to Intro Page

Interactive Nitrogen Cycle Joanne LaRuffa Robert Mullen Wade Thomason Susan Mullins Shannon Taylor Heather Lees Department of Plant and Soil Sciences Oklahoma State University Atmosphere Industrial Processes Plant and Animal Residues Lightning, Rainfall N2 Fixation %N > 1.5 (Animal Manure) %N < 1.5 (Wheat Straw) Microbial Decomposition Fertilizer Volatilization Immobilization Plant Loss Organic Matter N2, N2O, NO Plant/Microbial Sink NO3- Pool Back to Main Cycle Leaching Back to Intro Page

Interactive Nitrogen Cycle Joanne LaRuffa Robert Mullen Wade Thomason Susan Mullins Shannon Taylor Heather Lees Department of Plant and Soil Sciences Oklahoma State University Atmosphere Industrial Processes Plant and Animal Residues Lightning, Rainfall N2 Fixation Fertilizer Volatilization Plant Loss Organic Matter Temperature above or below 50°F? N2, N2O, NO Plant/Microbial Sink NO3- Pool Back to Main Cycle Leaching Back to Intro Page

Back to Temperature Choice Interactive Nitrogen Cycle Joanne LaRuffa Robert Mullen Wade Thomason Susan Mullins Shannon Taylor Heather Lees Department of Plant and Soil Sciences Oklahoma State University Atmosphere Industrial Processes Plant and Animal Residues Lightning, Rainfall N2 Fixation Fertilizer Volatilization Heterotrophic Aminization Plant Loss R-NH2 + Energy + CO2 Organic Matter Fungi pH < 6.0 Bacteria pH > 6.0 pH > 7.0 Ammonification R-NH2 + H2O Immobilization N2, N2O, NO R-OH + Energy + 2NH3 Plant/Microbial Sink Immobilization + H2O NO3- Pool 2NH4+ + 2OH- 2NH4+ + 2OH- Soil exchange sites + O2 Nitrosomonas + O2 Nitrobacter Back to Temperature Choice Back to Main Cycle 2NO2- + H2O + 4H+ Leaching Back to Intro Page

Interactive Nitrogen Cycle Joanne LaRuffa Robert Mullen Wade Thomason Susan Mullins Shannon Taylor Heather Lees Department of Plant and Soil Sciences Oklahoma State University Atmosphere Industrial Processes Plant and Animal Residues Lightning, Rainfall N2 Fixation Fertilizer Volatilization Plant Loss Amino Acids Organic Matter NH2OH NO2- N2O2- NH3 N2, N2O, NO Plant/Microbial Sink Immobilization Thiobacillus, T. Thioparus, Pseudomonas, Bacillus, and Dentrificans NO3- Pool Mineralization & Nitrification Denitrification Back to Main Cycle Leaching Back to Intro Page

Back to Temperature Choice Interactive Nitrogen Cycle Joanne LaRuffa Robert Mullen Wade Thomason Susan Mullins Shannon Taylor Heather Lees Department of Plant and Soil Sciences Oklahoma State University Atmosphere Industrial Processes Plant and Animal Residues Lightning, Rainfall N2 Fixation Fertilizer Volatilization Plant Loss Organic Matter N2, N2O, NO Plant/Microbial Sink NO3- Pool Back to Temperature Choice Back to Main Cycle Leaching Back to Intro Page

Interactive Nitrogen Cycle Joanne LaRuffa Robert Mullen Wade Thomason Susan Mullins Shannon Taylor Heather Lees Department of Plant and Soil Sciences Oklahoma State University Atmosphere Industrial Processes Plant and Animal Residues Lightning, Rainfall N2 Fixation Fertilizer Volatilization Plant Loss Organic Matter Immobilization N2, N2O, NO Plant/Microbial Sink NO3- Pool 2NH4+ + 2OH- Back to Main Cycle Leaching Back to Intro Page

Interactive Nitrogen Cycle Joanne LaRuffa Robert Mullen Wade Thomason Susan Mullins Shannon Taylor Heather Lees Department of Plant and Soil Sciences Oklahoma State University Atmosphere Industrial Processes Plant and Animal Residues Lightning, Rainfall N2 Fixation Fertilizer Volatilization Plant Loss Organic Matter N2, N2O, NO Plant/Microbial Sink Thiobacillus, T. Thioparus, Pseudomonas, Bacillus, and Dentrificans NO3- Pool Denitrification Back to Main Cycle Leaching Back to Intro Page

Interactive Nitrogen Cycle Joanne LaRuffa Robert Mullen Wade Thomason Susan Mullins Shannon Taylor Heather Lees Department of Plant and Soil Sciences Oklahoma State University Atmosphere Industrial Processes Plant and Animal Residues Lightning, Rainfall N2 Fixation Fertilizer Volatilization Plant Loss Organic Matter NH2OH NO2- N2O2- NH3 N2, N2O, NO Plant/Microbial Sink NO3- Pool Back to Main Cycle Leaching Back to Intro Page

Interactive Nitrogen Cycle Joanne LaRuffa Robert Mullen Wade Thomason Susan Mullins Shannon Taylor Heather Lees Department of Plant and Soil Sciences Oklahoma State University Atmosphere Industrial Processes Plant and Animal Residues Lightning, Rainfall N2 Fixation Fertilizer Volatilization Plant Loss Organic Matter N2, N2O, NO Plant/Microbial Sink NO3- Pool Back to Main Cycle Leaching Back to Intro Page

Interactive Nitrogen Cycle Joanne LaRuffa Robert Mullen Wade Thomason Susan Mullins Shannon Taylor Heather Lees Department of Plant and Soil Sciences Oklahoma State University Atmosphere Industrial Processes Plant and Animal Residues Lightning, Rainfall N2 Fixation Fertilizer Volatilization Heterotrophic Aminization Plant Loss R-NH2 + Energy + CO2 Organic Matter pH > 7.0 Ammonification R-NH2 + H2O N2, N2O, NO R-OH + Energy + 2NH3 Plant/Microbial Sink NO3- Pool Back to Main Cycle Leaching Back to Intro Page

Interactive Nitrogen Cycle Joanne LaRuffa Robert Mullen Wade Thomason Susan Mullins Shannon Taylor Heather Lees Department of Plant and Soil Sciences Oklahoma State University Atmosphere Industrial Processes Plant and Animal Residues Lightning, Rainfall N2 Fixation Haber-Bosch (1200C, 500 ATM) 3CH4 + 3O2 + 2N2  4NH3 + 3CO2 Fertilizer Volatilization Heterotrophic Aminization Plant Loss R-NH2 + Energy + CO2 Organic Matter N2, N2O, NO Plant/Microbial Sink NO3- Pool Back to Main Cycle Leaching Back to Intro Page

Nitrogen Information Form taken up plant Enzymes that require N Concentration in plants Mobility Deficiency symptoms Effect of pH on availability Soil pH deficiency Nutrient interactions Role of N in plant growth Fertilizer sources Role of N in microbial growth References

NH4+ NO3- Back to N Text Main Page Back to Intro Page

Soil Plant NH4+; NO NO3- ; Yes Yes Water Soluble Not influenced by soil colloids Plant Yes Back to N Text Main Page Back to Intro Page

Chlorosis in older leaves Under severe deficiency lower leaves are brown, beginning at the leaf tip and proceeding along the midrib Back to N Text Main Page Back to Intro Page

None due to nitrate’s mobility Back to N Text Main Page Back to Intro Page

N assimilation into amino acids for protein and amino acid synthesis Component of chlorophyll Vegetative growth Back to N Text Main Page Back to Intro Page

Necessary for the synthesis for amino acids Back to N Text Main Page Back to Intro Page

Nitrate reductase Nitrite reductase Nitrogenase Back to N Text Main Page Back to Intro Page

Wheat 1.7 to 3.0% Corn 2.7 to 3.5% Soybeans 4.2 to 5.5% Grain 2.0% Forage 3.0% Straw Corn 2.7 to 3.5% Soybeans 4.2 to 5.5% Grain sorghum 3.3 to 4.0 % Peanuts 3.5 to 4.5 % Alfalfa 4.5 to 5.0% Bermudagrass 2.5 to 3.0% Back to N Text Main Page Back to Intro Page

Low pH High pH None None at pH > 8 At pH > 7 NO2- accumulates Back to N Text Main Page Back to Intro Page

Si: enhances leaf erectness neutralizing the negative effects of high N supply on light interception P: symbiotic legume fixation needs adequate P, or a N deficiency can result Mo: component of nitrogenase, therefore could have Mo induced N deficiency in N2 fixing legumes Fe: Necessary for nitrogenase and ferredoxin, legume hemoglobin, deficiency reduces nodule mass, and nitrogenase Back to N Text Main Page Back to Intro Page

ammonium sulfate anhydrous ammonia ammonium chloride ammonium nitrate ammonium nitrate- ammonium nitrate sulfate with lime ammoniated ordinary- ammonium phosphate- superphosphate sulfate monoammonium phosphate diammonium phosphate ammonium polyphosphate ammonium thiophosphate calcium nitrate potassium nitrate sodium nitrate urea urea-sulfate urea-ammonium nitrate urea-ammonium phosphate urea phosphate Back to N Text Main Page Back to Intro Page

Burford, J. R. , and J. M. Bremner. 1975 Burford, J.R., and J.M. Bremner. 1975. Relationships between the denitrification capacities of soils and total, water-soluble and readily decomposable soil organic matter. Soil Biochem. 7:389-394. Marschner, H. 1995. Mineral Nutrition in Higher Plants. Academic Press, London. Tisdale, S.L., W.L. Nelson, J.D. Beaton, and J.L. Havlin. 1993. Soil Fertility and Fertilizers. MacMillan Publishing Co., New York, N.Y. Back to N Text Main Page Back to Intro Page