319 Targeted watershed program
• Best management practices include both urban and agricultural practices
• Urban examples include
– Waste water
– Storm water management
• Ag practices include:
– No-till
– Riparian zone management

319 Targeted watershed program
• The program also includes educational efforts
– Lawn and landscape nutrient management
– Cropland nutrient management
– Etc.
• Water monitoring a key component of
Oklahoma watershed program
– State operated monitoring sites
– Volunteer programs, (Blue thumb)

Oklahoma Carbon Sequestration
Certification Program
• Is voluntary
• The first to be run by a state agency with statutory authority to verify carbon offsets.
• Is developing verification protocols for grasslands, conservation tillage, rangeland, forestry, and geologic injection.
– Also interested in Methane Capture, and N2O reductions
• Provides a mechanism for Oklahomans to take advantage of existing voluntary carbon markets and future manditory markets.
• Supports and promotes soil carbon research.

Oklahoma Carbon Sequestration
Certification Program
• Provides certification of Carbon Aggregators:
– Promotes legitimate practices and reviews protocols
– Protects credit buyers from fraud
– Strengthens the value of credits generated in
Oklahoma

Oklahoma Carbon Sequestration
Certification Program
• Definitions:
– Aggregator: An intermediary that serves as the administrative representative for credit-generating projects on behalf of multiple and single landowners
• Protocol:
– Process by which credits are generated
– Can be practice based
• No-till adoption, grassland planting
• Simply verify that practices are implemented
– Or performance based
• Sequestration or avoidance must be quantified
• Monitoring or modeling
• Models are used for N
2
O emission avoidance credits

Oklahoma Carbon Sequestration
Certification Program
• Why is the Water Quality Division of the OCC in charge or carbon program?
• Because most practices that sequester GHG’s or avoid their emissions have positive impacts on water quality!
• Also, provides for privatization of conservation incentive programs

Oklahoma Carbon Sequestration
Certification Program
• Currently the OCC will certify credits generated from the following:
– Ag Credits:
• No-till conversion Grassland Planting
– Forestry Credits:
• Reforestation
• Afforestation
• Improved forest management
– Geologic injection

Oklahoma Carbon Sequestration
Certification Program
• The OCC is reviewing/developing protocols for the following:
– Rangeland carbon sequestration
– N2O emissions reduction from N fertilizer
– Methane capture from animal waste management

The Oklahoma Association of
Conservation districts; carbon credits
• The OACD serves as an aggregator:
– OKCarbon
– Contracts with large CO2 emitters to purchase
Credits from land owners
– They have also created the ECOpass and Ecobundle programs
–

• New effort by the Oklahoma Department of Tourism and Recreation to market the state to environmentally conscious tourists through the ECO program
• Gives travelers an option to offset the environmental impact of their trip
• They can purchase credits generated by conservation practices undertaken by farmers and ranchers on their land
– Carbon credits

• This is different than carbon credits
• This program is meant to generate a private funding source for wildlife habitat improvement.
– Specifically the lesser prairie chicken
• This program is well beyond carbon credits and is an excellent example of an ecosystems service market

• The conservation community has been working on the development of ecosystems service markets for a while:
• Nutrient trading programs:
– Polluters can decrease net discharge by paying landowners to implement BPM’s
• Wildlife habitat programs
– Destruction of habitat can be offset by creation of new habitat somewhere else
• These concepts have not gotten off the ground until now

• Concept:
– An industrial or municipal source can pay a farmer to decrease N and P runoff
• Problem:
– In general it is very difficult to quantify reduction in non-point source pollution and verify that BMP was implemented
– Carbon credits have the same problem but they have been somewhat over looked

• This concept has been studies for about 20 years
• On the surface it seams very simple?
– We stop tillage and carbon will accumulate in our soils
– Has a potential global impact because of the larger global pool of soil carbon
• However, there is much to learn about soil carbon cycling
• Most of the initial work was done on ≤6 inches of soil

380 ppm

What’s the Potential for Soil
Sequestration of CO
2
• The USDA estimates that U.S. Farms and
Rangeland could sequester 12-14% of current
U.S. CO
2 emission
• Much of this CO
2 will be sequestered through the reversal of soil carbon losses from:
– Cultivation
– Overgrazing

Soil Organic Carbon in Oklahoma
• Presettlement there were approximately 2.3 billion tons of carbon in Oklahoma Soils
• We have lost ~114 million tons of Carbon through cultivation:
– (38% of C in top 6 in)

Why do we lose Carbon after cultivation.
• Cultivation aerates the soil and breaks up soil aggregates.
– Aeration increases microbial respiration
– Organic Carbon is utilized for energy
• Incorporated residue is in close proximity to soil microbes
• Residue on the surface is not readily decomposed.

Impact of Tillage on Soil Carbon cycle
Atmosphere
CO
2
Soil Respiration
(Decomposition)
Soil Organic Carbon
Living biomass
Carbohydrates
Carbon storage
Soil respiration is equal is greater than plant residue deposition.
Net loss of Carbon

80
Magruder Plots, Stillwater:
Soil Carbon loss after 110 years of Continuous
Wheat
Soil Carbon Loss in Top 6 inches
• Initial C was 1.8%
• Lost 46 to 70% of the initial C.
• ~28-42 Mt CO
2
/acre
• 2300 to 3400 gal of gasoline/acre!
60
40
20
0
Check P NP NPK NPK Lime Manure

Change in Soil Carbon Cycle when Tillage is Removed
Atmosphere
CO
2
Soil Respiration
(Decomposition)
Soil Organic Carbon
Living biomass
Carbohydrates
Carbon storage
Soil respiration is reduced and
Organic carbon accumulates.

Other Factors influencing soil Carbon
Sequestration
• Crop Residue input in to soil system
• Crop Residue Quality

The rate of Carbon Sequestration is also Impacted by
Residue Input
Atmosphere
CO
2
Soil Respiration
(Decomposition)
Soil Organic Carbon
Living biomass
Carbohydrates
Carbon storage
Plant residue deposition is reduced
Carbon storage is reduced

Successful practices for soil carbon sequestration
• Soil management must result in the same or greater input of organic residues
– Inclusion of highly resistant residues in the rotation is important
– No-till soybeans will not increase soil carbon
– Wheat, corn sorghum, etc are more resistant to decompostion
• Total soil respiration must be reduced
– I thought that no-till increased microbial activity?

• No-till certainly increases the base-line mircrobial activity
• However, it reduces the maximum rate of decomposition observed after tillage events
• The impact of total (annual) soil respiration will be dependent on its impact on soil moisture and temperature
– Do they become more optimum for microbial activity
– Likely so, but how much more optimum?

The Current State of our
Understanding
• Removal of tillage from our cropland systems will increase soil organic carbon in the topsoil given that inputs are not reduced
• High level of uncertainty about what is happening in the subsoils
• Recently, research has suggested that no-till may cause a decline in subsoil carbon?

Problem with Using Shallow Samples
 Potential errors due to deeper rooting in cultivated soils.
 0-7.5 inch samples give sequestration rate of:
 3 Mt CO
2
/acre/yr
 0-20 inches gives:
 2.3 Mt CO
2 acre/yr
 It is important to evaluate
0 whole soil to provide accurate estimates of sequestration
5
10
15
Conventional tillage
No-Till
20
Blanco-Canqui, and Lal, 2008
Central Kentucky
25
0 2 4 6
Soil Organic Carbon (Mt/acre)
8 10

• Potential mechanisms responsible for decrease in subsoil carbon:
• Decrease in transfer of carbon through tillage
– We are simply changing the distribution of carbon
• Decreased rooting depth
• Decrease subsoil moisture resulting in increased microbial activity (improved aeration)

• Whole profile assessment is very important but very difficult
• Analysis of profile carbon results in an assessment of a very small change in a very large carbon pool.
• Therefore, it will take many years to fully understand the impacts of management on whole soil carbon

Simple Difference in Carbon Stocks Among Notill and Conventional Tillage
0
10
20
Difference
2.4 Mton
Average of all Soils collected
Difference
2.0 Mtons
Difference
1.7 Mton
NS
NS
*** (p<0.05)
20 Mton acre-1
38 Mton acre-1
NS 70 Mton acre-1
30 120 Mton acre-1
NS
40
Conventional
No-Till
150 Mton acre-1
50
1 2 3 4
Mton CO
2
acre
-1
inch
-1
5 6 7