Soil Carbon Sequestration:

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Soil Carbon Sequestration Long-term Effect of
Tillage and Rotations
Charles W. Rice and Karina Fabrizzi
Kansas State University
October 28-30, 2008
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Global economic mitigation potential for
different sectors at different carbon prices
IPCC, 2007
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Agriculture

• A large proportion of the mitigation potential of
  agriculture (excluding bioenergy) arises from
  soil C sequestration, which has strong synergies
  with sustainable agriculture and generally
  reduces vulnerability to climate change.
• Agricultural practices collectively can make a
  significant contribution at low cost
• By increasing soil carbon sinks,
• By reducing GHG emissions,
• By contributing biomass feedstocks for energy use
  

IPCC Fourth Assessment Report, Working Group III,
2007
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Agriculture

• Rice paddies
• Irrigation
• Chemical and organic fertilizer
• Plant residue management

• Cropland
• Reduced tillage
• Rotations
• Cover crops
• Fertility management
• Erosion control
• Irrigation management

Rice fields in The Philippines

• Agroforestry
• Improved managementof trees and cropland

No-till seeding in USA
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Agricultural Management Strategies for C
Sequestration
Develop Agricultural Management Programs that
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Climate
Soils
Management
CO2
Sunlight
Harvestable Yield
Soil Microbial Activity Soil Organic Matter (C)
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Potential C sequestration in U.S
Lal et al., 1999, Post et al.,2004
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Corn production in NE Kansas

• Continuous corn
• 168 kg N/ha
• Tillage Systems
• No-tillage
• Conservation tillage (Chisel-disk)
• 15 year analysis

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Soil C stocks after 18 years



Nicoloso et al., 2008
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Tillage effects on soil organic C by depth,
Minnesota 14 y continuous cornMg C/ha/cm
Huggins et al., 2007
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)
1
-
E
SOC levels (Mg C ha
O
A
Change in management
Years of cultivation
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Soil C sequestration rates for 15 years(Mg
C/ha/y)

• NT gt Tilled, but tilled had some increase
• Added C (manure) is less conserved in tilled
• What is baseline?

Nicoloso et al., 2008
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)
1
-
E
SOC levels (Mg C ha
D
O
C
A
Change in management
Years of cultivation
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Net effect of NT for 15 yearsNT (0-15y) T
(0-15y)
Nicoloso et al., 2008
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Carbon sequestration rate (C rate) expressed in
equivalent mass (Mg C/ha/y) to a 30 cm depth
except for Hayes (15 cm)
Fabrizzi, 2006
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11 Line
Intergovernmental Panel on Climate Change (IPCC)
1.1 for CT to NT West and Post (2002) 1.16 for
CT to NT
Fabrizzi, 2006
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Carbon sequestration rate (C rate) expressed in
equivalent mass (Mg C/ha/y) to a 15 cm depth as a
function of N rate (kg N/ha/y) located Hayes,
Kansas, USA
Fabrizzi, 2006
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Carbon sequestration rate (C rate) expressed in
equivalent mass (Mg C/ha/y) to a 30 cm depth for
Manhattan, KS USA
Fabrizzi, 2006
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Conservation of Soil Carbon
H2O
Organic C
Temperature
Microbial composition and activity
O2
Management
Substrate quality
Plant characteristics
Clay
Hierarchy of importance
Biological factors
Physical Protection
Disturbance
Organics
Chemical
Mineralogy
Clay
CO2
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• Fungal Role (182w6 biomarker)
• Significant tillage X residue interaction (plt0.05)

Frey et al. (1999) found greater fungal networks
optically in NT as compared to CT for the same
soil.
White and Rice, 2007
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White and Rice, 2007
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Fabrizzi, 2006
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No-Tillage Cropping Systems Conservation
Agriculture

• Restores soil carbon
• Conserves moisture
• Saves fuel
• Saves labor
• Lowers machinery costs
• Reduces erosion
• Improved soil fertility
• Controls weed
• Planting on the best date
• Improves wildlife habitat

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Summary

• Soil C sequestration
• Need to examine the system
• Less disturbance
• Organic C inputs
• No-tillage must be combined with residues
• Residue removal in no-till may be worst than
  tillage with residue
• Agricultural soil C sequestration
• Keeps land in production in some cases
• In many cases increases profitability for the
  farmer
• Provides other environmental benefits to society
• Soil and Water quality (less runoff, less
  erosion)
• May help adapt to climate change as well as
  mitigate

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Chuck Rice Phone [phone] Cell
785-587-7215 cwrice_at_ksu.edu

• Websites
• www.soilcarboncenter.k-state.edu/

K-State Research and Extension
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