N fertilizer placements and greenhouse gas emissions from - PowerPoint PPT Presentation

N fertilizer placements and greenhouse gas emissions from continuously flooded rice systems M. Arlene Adviento-Borbe 1 and Bruce Linquist 2 1 Delta Water Management Research Unit, USDA-ARS, Jonesboro, AR 2 Dept. of Plant Sciences, University of California, Davis, CA 3 rd PRRG-GRA Americas meeting, July 13-15, 2016 DBNRRC Stuttgart, AR Delta Water Management Research Unit

Emissio Emis ions of f CH 4 and nd N 2 O pr prod oduced from om agri gricult ltural al activ tivit itie ies (1961-2011) 2011) (20-40 Mt of CH 4 per year) Source: FAOSTAT Delta Water Management Research Unit

Processes s cau ausing em emiss issions of of CH 4 fr from flood flooded ric ice fiel fields Atmosphere CH 4 O 2 O 2 CH 4 CH 4 Rice Plant Floodwater CH 4 + 2O 2 CO 2 + H 2 O Bulk soil Rice Roots Rhizosphere CH 3 COOH CO 2 + CH 4 CO 2 + 4H + 2H 2 O + CH 4 CH 4 + 2O 2 CO 2 + H 2 O , H + O 2 Delta Water Management Research Unit

Processes s cau ausing em emiss issions of of N 2 O fr from floo flooded ric ice fiel fields Atmosphere O 2 N 2 O N 2 O O 2 NH 3 + NH 4 Rice Plant N 2 O Rice Roots Reduced soil Oxidized soil N 2 O - - NO 2 NO + N 2 O NO 3 + NH 4 NH 3 - NO 3 N 2 O 2 , H + Delta Water Management Research Unit

US S Nit itrous oxi xide em emis issi sions s by sou source (1 (1990-2014) Delta Water Management Research Unit

Current de default N 2 O emis emissi sion fac actor for or dir direct emis emissio ions E N2O = 1 + 0.0125*F 0.21 to 0.40% fertilizer-induced N 2 O emission Source: Bouwman 1996. Nutrient Cyc. Agroeco.52, 165-170. Delta Water Management Research Unit

Management pr practi tices for red educing GHG em emissions 1. Water management • Alternate wetting & drying 2. Rice selections • Hybrids vs conventional 3. Placement of N fertilizer • Subsurface application 4. Forms of N • Ammonium sulfate • Urease inhibitor 5. Time of N application • Multiple application 6. Amount of fertilizer N • Suboptimal rates • Optimal rates Delta Water Management Research Unit

Management pr practi tices for red educing GHG em emissions 1. Water management • Alternate wetting & drying 2. Rice selections • Hybrids vs conventional 3. Placement of N fertilizer • Subsurface application 4. Forms of N • Ammonium sulfate • Urease inhibitor 5. Time of N application • Multiple application 6. Amount of fertilizer N • Suboptimal rates • Optimal rates Delta Water Management Research Unit

Mitigating CH CH 4 em emissions in n flooded ric rice fields Atmosphere CH 4 O 2 O 2 Rice Plant Floodwater Bulk soil Rice Roots Rhizosphere CH 3 COOH CO 2 + CH 4 CO 2 + 4H + 2H 2 O + CH 4 CH 4 + 2O 2 CO 2 + H 2 O , H + O 2 Delta Water Management Research Unit

Management pr practi tices for red educing GHG em emissions 1. Water management • Alternate wetting & drying 2. Rice selections • Hybrids vs conventional 3. Placement of N fertilizer • Subsurface application 4. Forms of N • Ammonium sulfate • Urease inhibitor 5. Time of N application • Multiple application 6. Amount of fertilizer N • Suboptimal rates • Optimal rates Delta Water Management Research Unit

Infl fluenc nce of of N N fert rtil iliz izer on on N 2 O O emi miss ssio ions in n fl floo ooded ri rice ce fi field lds Atmosphere 18% increase in N 2 O emission O 2 N 2 O Fertilizer N N 2 O NH 3 NH 4 + O 2 Rice Plant Oxidized soil N 2 O Rice Roots Reduced soil N 2 O - - NO 2 NO + N 2 O X NO 3 + NH 4 NH 3 - NO 3 N 2 O 2 , H + Delta Water Management Research Unit

Infl fluenc nce of of N N fert rtil iliz izer on on CH 4 em emission ions in n fl floo ooded ri rice ce fi field lds N-rate dependent CH 4 emissions: Low-to-moderate vs. high N rates Atmosphere Deep-placed fertilizer N = 40% reduction of CH 4 emission CH 4 O 2 O 2 Fertilizer N (band) CH 4 NH 3 NH 4 + Rice Plant Floodwater CO 2 + H 2 O CH 4 + 2O 2 Bulk soil Rice Roots Rhizosphere CH 3 COOH CO 2 + CH 4 CO 2 + 4H + 2H 2 O + CH 4 CH 4 + 2O 2 CO 2 + H 2 O , H + O 2 Delta Water Management Research Unit

Field experiments ts Locations: Field 1 – Agricultural Research Farm, University of California, Davis, CA Field 2 – California Rice Research Experimental Station, Biggs, CA Field 3 - Commercial rice grower’s field, Marysville, CA N treatments: 1. Broadcast N – surface applied N fertilizer 2. Banded N – injected/applied 7.5 cm below soil surface Delta Water Management Research Unit

Obj Objectives 1. To asses various N fertilizer placements in reducing methane (CH 4 ) and nitrous oxide (N 2 O) emissions from irrigated rice systems, and 2. To quantify grain yield under different N fertilizer management practices Delta Water Management Research Unit

N N fertilizer treatments Site Location Rice Treatment Fertilizer Fertilizer Location of variety Code N rate Type Fertilizer N application a kg N ha -1 Field 1 UC Davis M104 F1-N0 0 NA NA Field 1 UC Davis M104 F1-BR 150 Urea Surface Field 1 UC Davis M104 F1-BA 150 Urea Subsurface Field 2 RES, Biggs M206 F2-N0 0 NA NA Field 2 RES, Biggs M206 F2-BR 150 Urea Surface Field 2 RES, Biggs M206 F2-BA 150 Urea Subsurface Field 3 Marysville, CA M206 F3-N0 0 NA NA Field 3 Marysville, CA M206 F3-BR 143 Urea Surface Field 3 Marysville, CA M206 F3-BA 143 Urea Subsurface a subsurface application is placing urea 7.5 cm below the soil surface. Delta Water Management Research Unit

Mea easurements ts of of CH CH 4 and and N 2 O em emis issio ions  varying chamber height (13 - 122  30.5 cm diameter vented flux  12 mL gas vial double sealed with cm; 8-90 L) based on height of chamber with 17 CFM/5800 RPM silicon growing rice fan  Multi-point valves GC-2014 gas  daily to weekly gas sampling (90+ chromatograph with a 63 NI ECD and sampling dates) FID detectors Delta Water Management Research Unit

N N fertilization affects gr grain yi yield N0 18 Broadcast Subsurface Banded Grain yield, Mg ha -1 15 a a a a a a b 12 9 6 b b 3 0 Field 1 Field 2 Field 3 Significant at 95% confidence level Delta Water Management Research Unit

N N fertilization affects gr grain yi yield Grain Yield, Mg ha - Fertilizer N Relative % Relative Yield 1 placements increase to change to surface surface application application Field 1 N0 4.05b F1-BR 11.1a F1-BA 12.2a 10 1.1 Field 2 N0 3.66b F2-BR 10.3a F2-BA 12.1a 17 1.8 Field 3 N0 10.9b F2-BR 12.2a F2-BA 12.5a 2.5 0.3 Delta Water Management Research Unit

ha -1 d -1 N fert ertili lizer plac placements an and CH 4 em emis issi sions, s, kg g CH 4 -C ha Field 2: Biggs, CA 6000 18 N0 (Control) Floodwater height, cm 5000 16 Broadcast Subsurface Banded 14 Floodwater Height 4000 12 3000 10 8 2000 6 1000 4 0 2 0 May 01 May 16 May 31 Jun 15 Jun 30 Jul 15 Jul 30 Aug 14 Aug 29 Sep 13 Sep 28 Oct 13 Date of sampling Delta Water Management Research Unit

ha -1 d -1 N fert ertili lizer plac placements an and N 2 O emis emissio ions, g g N 2 O-N ha Field 2: Biggs, CA 18 15 N0 (Control) Floodwater height, cm Broadcast 16 Subsurface Banded 14 Floodwater Height 10 12 10 5 8 0 6 4 -5 2 0 May 01 May 16 May 31 Jun 15 Jun 30 Jul 15 Jul 30 Aug 14 Aug 29 Sep 13 Sep 28 Oct 13 Date of sampling Delta Water Management Research Unit

Glob lobal l war arming g po potentia ials ls and nd Fe Fert rtil iliz izer-in induced N 2 O emis issio ions in n di different N treatments and nd sites Fertilizer N CH 4 emissions N 2 O emissions Fertilizer- kg CO 2 eq ha -1 kg CO 2 eq ha -1 placements induced N 2 O season -1 season -1 emissions, % Field 1 N0 210a -6.6a F1-BR 409a -23a (0.02) F1-BA 453a -12a (0.01) Field 2 N0 2,085b -30a F2-BR 4,438a -33a (0.01) F2-BA 3,834a -50a (0.04) Field 3 N0 8,994a 4.7a F2-BR 9,910a -35a (0.06) F2-BA 7,711a -6.0a (0.02) Delta Water Management Research Unit

Glob lobal l war arming pot potentials ls in in dif different N treatments and and sit sites Fertilizer N GWP, Relative % GWP Y , Relative % kg CO 2 eq ha -1 kg CO 2 eq Mg -1 placements decrease to decrease to season -1 season -1 surface surface application application Field 1 N0 204a 46a F1-BR 385a 33a F1-BA 440a (14) 35a (6) Field 2 N0 2,055b 574a F2-BR 4,405a 449a F2-BA 3,784a 14 311a 31 Field 3 N0 8,999a 824a F2-BR 9,875a 808a F2-BA 7,705a 22 616a 24 Delta Water Management Research Unit

Infl fluenc nce of of N N fert rtil iliz izer on on CH 4 em emission ions in n fl floo ooded ri rice ce fi field lds N-rate dependent CH 4 emissions: Low-to-moderate vs. high N rates Atmosphere Deep-placed fertilizer N = 40% reduction of CH 4 emission CH 4 O 2 O 2 Fertilizer N (band) CH 4 NH 3 NH 4 + Rice Plant Floodwater CO 2 + H 2 O CH 4 + 2O 2 Bulk soil Rice Roots Rhizosphere CH 3 COOH CO 2 + CH 4 CO 2 + 4H + 2H 2 O + CH 4 CH 4 + 2O 2 CO 2 + H 2 O , H + O 2 Delta Water Management Research Unit