influence of swine manure application method on concentrations of methanogens and denitrifiers in...
DESCRIPTION
Proceedings available at: http://www.extension.org/67590 Soil microbial communities have been proposed as indicators of soil quality due to their importance as drivers of global biogeochemical cycles and their sensitivity to management and climatic conditions. Despite the importance of the soil microbiota to nutrient transformation and chemical cycling, physio-chemical properties rather than biological properties of soils are traditionally used as measures of environmental status. In general, much is unknown regarding the effect of management fluctuations on important functional groups in soils systems (i.e., methanogens, nitrifiers and denitrifiers). It is only recently that it has been possible, through application of sophisticated molecular microbiological methods, to sensitively and specifically target important microbial populations that contribute to nutrient cycling and plant health present at the field-scale and in differentially managed soil systems.TRANSCRIPT
Influence of Swine Manure Influence of Swine Manure Application Method on Application Method on
Concentrations of Methanogens Concentrations of Methanogens and Denitrifiers in Agricultural and Denitrifiers in Agricultural
SoilsSoilsKimberly Cook & Karamat Kimberly Cook & Karamat
SistaniSistani
Bowling Green, KYBowling Green, KY
Microbes & Biogeochemical Microbes & Biogeochemical CyclesCycles
Indicators of soil qualityIndicators of soil quality Drivers of global biogeochemical cyclesDrivers of global biogeochemical cycles Sensitive to soil managementSensitive to soil management Sensitive to climate conditionsSensitive to climate conditions
Physical vs BiologicalPhysical vs Biological Traditional measures focused on physio-chemicalTraditional measures focused on physio-chemical Molecular methods contribute to microbial Molecular methods contribute to microbial
analysesanalyses Better understand relationship between Better understand relationship between
physical, chemical and biological processes physical, chemical and biological processes in agricultural systemsin agricultural systems
Microbes & GHGMicrobes & GHG Major Ag associated GHG: COMajor Ag associated GHG: CO22,, CHCH44 & N & N22OO Bacteria are largest producers of methane Bacteria are largest producers of methane
and Nand N22OO Methane production Methane production
Complex anaerobic consortiaComplex anaerobic consortia Fermentative bacteria & methanogenic archaeaFermentative bacteria & methanogenic archaea Livestock and soilsLivestock and soils Anaerobic manure management systemsAnaerobic manure management systems
NN22O from denitrification (anaerobic) and O from denitrification (anaerobic) and nitrification (anaerobic)nitrification (anaerobic)
Cause & EffectCause & Effect
How does management or How does management or environment affect GHG production?environment affect GHG production?
How does management or How does management or environment affect environment affect bacteria that bacteria that produceproduce GHG? GHG?
Swine Effluent Application Swine Effluent Application StudyStudy
Evaluate the effect of pre-plant swine Evaluate the effect of pre-plant swine effluent application method on GHG effluent application method on GHG (CO(CO2 2 ,CH,CH44 & N & N22O) emissions from soil in a O) emissions from soil in a no-till corn grain production systemno-till corn grain production system
Sistani, K.R., Warren, J.G., Lovanh, N.C., Sistani, K.R., Warren, J.G., Lovanh, N.C., Higgins, S., Shearer, S. 2010. Green Higgins, S., Shearer, S. 2010. Green House Gas Emissions from Swine Effluent House Gas Emissions from Swine Effluent Applied to Soil by Different Methods. Soil Applied to Soil by Different Methods. Soil Sci. America J. 74(2): 429-435. Sci. America J. 74(2): 429-435.
MethodsMethods
Two growing seasons of no-till cornTwo growing seasons of no-till corn Gases measured using vented Gases measured using vented
chamberschambers Three effluent application methods Three effluent application methods
SurfaceSurface Direct InjectionDirect Injection Plus AerationPlus Aeration
Microbiology – one sample point 2 Microbiology – one sample point 2 weeks after application in 2008weeks after application in 2008
InjectionInjection
Surface Surface ApplicationApplication
AerationAeration Methods ofMethods of Swine Manure Swine Manure
ApplicationApplication
COCO22 production production similar in all similar in all treatmentstreatments
No influence of No influence of swine effluent swine effluent applicationapplication
Total bacterial cell numbers similar in all Total bacterial cell numbers similar in all treatmentstreatments
Total fungal cell numbers similar in all Total fungal cell numbers similar in all treatmentstreatments Averaged 3 orders of magnitude lower than total Averaged 3 orders of magnitude lower than total
cells cells
CHCH44 higher in higher in injection treatmentinjection treatment
Emissions spiked for Emissions spiked for up to 11 days after up to 11 days after applicationapplication
Concentrations of methanogens (Concentrations of methanogens (mcrAmcrA) ) were up to 7 orders of higher than were up to 7 orders of higher than backgroundbackground
Methane oxidizers (Methane oxidizers (pmoApmoA) were up to ) were up to 6 orders of magnitude higher6 orders of magnitude higher
NN22O flux highest in O flux highest in injection treatmentinjection treatment
Peak in flux at 6 dPeak in flux at 6 d However, aeration & However, aeration &
injection treatments injection treatments continued to increase & continued to increase & peaked after 18 dpeaked after 18 d
NitrifiersNitrifiers
DenitrifiersDenitrifiersNitrate Reducers; Nitrate Reducers; narGnarGNitrite Reducers; Nitrite Reducers; nirKnirKNitrous Oxide Reducers; Nitrous Oxide Reducers; nosZnosZ
Nitrate Reducers; Nitrate Reducers; narGnarG
ConclusionsConclusions
Two groups showed significant Two groups showed significant response to effluent applicationresponse to effluent application Nitrifying Bacteria (AOB)Nitrifying Bacteria (AOB) Nitrate Reducers (Nitrate Reducers (narGnarG))
Methanogens and methane oxidizers Methanogens and methane oxidizers also increased orders of magnitude but also increased orders of magnitude but were brought in with slurrywere brought in with slurry
Sampling method, targeted genes and Sampling method, targeted genes and analysis method are all significantanalysis method are all significant
Integrating MicrobiologyIntegrating Microbiology Integrate into field analyses; incorporate Integrate into field analyses; incorporate
thinking into management practicesthinking into management practices Biological perspectiveBiological perspective
Enzyme dependent pHEnzyme dependent pH Requirement for co-factorsRequirement for co-factors
Mitigation of NMitigation of N22OO in atmosphere exclusively carried out by nitrous oxide reducers nitrous oxide reducers (nosZ)(nosZ) Requires 12 Copper ionsRequires 12 Copper ions Optimum pH over 7Optimum pH over 7
CollaboratorsCollaborators
Special thanks to Dr. Jason Warren Special thanks to Dr. Jason Warren (OK State University) for collaborative (OK State University) for collaborative efforts on this projectefforts on this project
Thanks also to Rohan Parekh and Jason Thanks also to Rohan Parekh and Jason Simmons for technical assistanceSimmons for technical assistance
This research was conducted as part of This research was conducted as part of USDA-ARS National Program 214: USDA-ARS National Program 214: Agricultural and Industrial By-ProductsAgricultural and Industrial By-Products