Soil Carbon Sequestration in Agriculture Scott Staggenborg and Charles W. Rice Department of Agronomy K-State Research and Extension

Strategies to Reduce Atmospheric CO 2 Strategies Reduce fossil fuel consumption Improve efficiency Renewable energy sources Identify sinks and sequestration rate Terrestrial SoilsPlants Aquatic Geologic

Soil C sequestration potential of different US land Categories (% of 322 MMT C/yr) ** US land Categories (% of 322 MMT C/yr) **

Improved Agricultural Practices Conservation tillageConservation buffers Cover crops Improved rotations Soil organic matter CO 2

Soil Organic Matter (Humus) CO 2 product energy Climate Management Soil Type

Crop Management Strategies for C Sequestration Develop Crop Management Programs that:

Enhancing C Input – Fertility C-C NF

Enhancing C Input – Crop Selection

Crop Management Strategies for C Sequestration To increase soil carbon levels, we need crop rotations that reduce fallow periods. Especially rotations with fallow periods during the summer when temperatures result in maximum soil respiration rates.

Enhancing C Input – Intensifying Rotations

21.2 MMTC yr -1 on 149 Mha cropland Preliminary inventory results-- Century

Crop Management Strategies for C Sequestration Eastern Colorado

Crop Management Strategies for C Sequestration Develop Crop Management Programs that:

Why Tillage –Eliminate soil compaction –Control weeds –Eliminate residue Harbor insects and diseases Tie up fertilizer N Barrier for herbicide –What hard working people do Sense of accomplishment Cleansing operation Why not? Because it causes soil erosion and reduces soil organic matter

Enhancing C Input – Tillage C-C NF

Reducing Loss – Reducing tillage

Enhancing C Input – Tillage NE W-F

Soil organic C after 2 and 12 y of CRP in Nebraska (Baer, Kitchen, Blair, and Rice) 0.4 Tons/a/y

Soil Organic Matter Water Holding Capacity Crop Yield Soil Biodiversity Root growth Nutrient Reserves Soil Structure Plant Biomass Soil Quality Lal, Kimble, and Follett 1997

Carbon Credits/Trading Carbon reduction –C reduction at point of emissions –C reduction by sequestration Is it cheaper to buy a credit than control emissions?

What is needed Sellers of C credits: Land managers Aggregator Buyers Monitoring/Verification

Examples of feasibility and pilot projects on soil carbon sequestration RegionLand UseLand management change Saskatchewan, CanadaCroplandDirect seeding / cropping intensification Pacific Northwest, USACroplandDirect seeding / cropping intensification Midwest Iowa, Kansas Cropland Grass planting No-till New grass plantings Oaxaca, MexicoCrop / natural fallow secondary forest Fruit tree intercrops with annual crops / Conservation tillage Pampas, ArgentinaCroplandDirect seeding KazakhstanCroplandAgriculture to grassland Izaurralde (2004)

Offsets for no-till or grasses Offsets for grasses only U.S. Central Region for CCX ® Soil Offsets

Kansas MRLAs and Carbon Pilot Counties

Tillage Equipment Full width inversion –Moldboard plow –Chisel plow –Field cultivator –Tandem disk –Offset disk –Row crop cultivator Okay to use –No-till/ridge-till planter –No-till drill –Rolling harrow –Subsoiler/ripper –Anhydrous applicator –Manure knife applicator General Guideline: After the implement has been through the field, there must still be a substantial amount of surface residue present and the soil disturbance must not be full width. If use of the implement would require that a leveling or smoothing activity follow, it would probably result in too much soil disturbance.

Mechanics of Ag Offset Aggregation in CCX ® Aggregators - accepts initial registrations from producers - assembles annual attestations of activities from producers - receives offsets into CCX registry account from - executes sales on CCX trading platform on behalf of growers - manage multi-grower reserve account Individual Growers - register; undertake actions as per 4-year contract; sign annual attestations; allow access to CCX verifiers; ultimate owner of offsets CCX - issues offsets to aggregator’s registry account - commissions verifiers documentation offsets documentationsales proceeds

2004 Carbon Offset Prices

Potential Partners KSU Research and Extension –Other universities Federal –NRCS State Agencies –State Conservation Commission –Department of Agriculture –Department of Commerce NGO’s –RC & D –KACD –Others? Businesses

Consortium for Agricultural Soil Mitigation of Greenhouse Gases To provide the tools and information to successfully implement soil carbon sequestration so that –the accumulation of greenhouse gases is lowered in the atmosphere, –while providing income and incentives to farmers and improving the soil. Kansas State UniversityColorado State University Iowa State UniversityMichigan State University Montana State UniversityUniversity of Nebraska Ohio State UniversityPurdue University Texas A&M UniversityPacific Northwest National Labs

Kansas Coalition for Carbon Management Mission –To inform, educate and motivate land managers to apply management practices that result in reduced atmospheric carbon levels Website –

Kansas Coalition for Carbon Management Objectives –Inform and educate land managers on carbon management practices –Encourage research of greenhouse gas emission reduction and alternative energy uses –Explore and disseminate marketing opportunities as they develop. –Investigate the legal boundaries around carbon sequestration.

Kansas Coalition for Carbon Management Kansas Resource Conservation and Development Councils Kansas Corn Growers Association Kansas Grain Sorghum Producers Association Kansas Association of Wheat Growers Kansas Electric Power Cooperative Kansas Forage and Grasslands and Society for Range Management Kansas Livestock Association Kansas Farm Bureau Kansas Rural Center Kansas Association of Conservation Districts Kansas Department of Agriculture State Conservation Commission Kansas Department of Health and Environment USDA Natural Resources Conservation Service USDA Farm Services Agency Kansas Sate University Member Organizations

Cropping System Changes and Carbon TreatmentScenarioRate (Mg C/ha/y) Rate (Mg C/ha/y) Duration (yrs) State Conservation tillage wheat/sorghum/fallow rotation 037Semi-arid KS Eliminate summer fallow 3-year system 4-year system Continuous cropping Eastern Colorado Integrated Nutrient Management (corn) NT 150 N manure NT 150 N Fert CT 150 N manure NE Kansas RotationsCT - NT wheat CT - NT sorghum CTsorg/NTwheat to NT sorg/wheat SC KS

TreatmentScenarioRate (Mg C/ha/y) Rate (Mg C/ha/y) Duration (yrs) State Conservation tillage wheat/sorghum/fallow rotation 037Semi-arid KS Farming systems NT corn NT corn rotate w/ grass meadow NT corn rotate w/ alfalfa and manure Corn-soybean with poultry manure NE Ohio

Soil organic C measurement/verification How can this be done accurately and economically? Physical measurements will be part of any rational sampling scheme, but how best to array a limited number of samples? Modeling of some type, whether ecosystem modeling or statistical extrapolation/interpolation, is required to fill in knowledge gaps from sampling. Some combination of the two is needed.

Sampling strategies will need to account for variable landscapes

Questions?

Potential of U.S. Cropland for C Sequestration, Fossil Fuel Off-set,& Erosion Control Lal et al., 1999

Soil Sampling for Measuring Soil C Soil C storage depends on soil area and thickness or mass –Report on volume basis Need to sample: –Laterally across the landscape to account for spatial variability due to: topography erosion soil mapping units management (tillage, inputs). –Vertically through the profile to account for horizonation, tillage, residue and root inputs

Sampling scheme MeanSDCV%n†n† Grid Grid Grid Average Composite Composite Composite Average Variability of soil C (Mg ha -1 ) for an agricultural site