319 targeted watershed program best management practices include both urban and agricultural...
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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 N2O 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 Eco-
bundle programs –
ECOpass• 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
Eco-Bundle Program
• 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
Ecosystems Service Markets
• 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
Nutrient Trading
• 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
Soil Carbon Sequestration
• 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 CO2
• The USDA estimates that U.S. Farms and Rangeland could sequester 12-14% of current U.S. CO2 emission
• Much of this CO2 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
photosynthesisphotosynthesis
Plan
t Pl
ant
Resp
iratio
nRe
spira
tion
Plant Plant
ResidueResidue
Soil Organic CarbonSoil Organic CarbonCarbon storageCarbon storage
Soil respiration is equal is greater than plant residue deposition.Net loss of Carbon
Living biomassLiving biomassCarbohydratesCarbohydrates
AtmosphereAtmosphereCOCO22
Soil RespirationSoil Respiration(Decomposition)(Decomposition)
Magruder Plots, Stillwater:Soil Carbon loss after 110 years of Continuous
Wheat• Initial C was 1.8%• Lost 46 to 70% of the
initial C.• ~28-42 Mt CO2/acre
• 2300 to 3400 gal of gasoline/acre!
Soil Carbon Loss in Top 6 inches
Check P NP NPK NPK Lime Manure
Org
anic
C lo
st (
% o
f in
itia
l)
0
20
40
60
80
Change in Soil Carbon Cycle when Tillage is Removed
photosynthesisphotosynthesis
Plan
t Pl
ant
Resp
iratio
nRe
spira
tion
Plant Plant
ResidueResidue
Soil Organic CarbonSoil Organic CarbonCarbon storageCarbon storage
Soil RespirationSoil Respiration(Decomposition)(Decomposition)
Soil respiration is reduced and Organic carbon accumulates.
Living biomassLiving biomassCarbohydratesCarbohydrates
AtmosphereAtmosphereCOCO22
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
photosynthesisphotosynthesis
Plan
t Pl
ant
Resp
iratio
nRe
spira
tion
Plant Plant
ResidueResidue
Soil Organic CarbonSoil Organic CarbonCarbon storageCarbon storage
Soil RespirationSoil Respiration(Decomposition)(Decomposition)
Plant residue deposition is reduced Carbon storage is reduced
Living biomassLiving biomassCarbohydratesCarbohydrates
AtmosphereAtmosphereCOCO22
Plant Plant ResiduResidu
ee
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?
Total Soil Respiration• 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 CO2/acre/yr
0-20 inches gives: 2.3 Mt CO2acre/yr
It is important to evaluate whole soil to provide
accurate estimates of sequestration
Soil Organic Carbon (Mt/acre)
0 2 4 6 8 10
So
il D
epth
(in
ches
)
0
5
10
15
20
25
Conventional tillageNo-Till
Blanco-Canqui, and Lal, 2008Central Kentucky
Whole soil Profile Assessment• 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 soil Profile Assessment
• 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
Mton CO2 acre-1 inch-1
1 2 3 4 5 6 7
De
pth
(in
ch
es)
0
10
20
30
40
50
Conventional No-Till
Simple Difference in Carbon Stocks Among No-till and Conventional Tillage
Difference2.4 Mton
Difference1.7 MtonDifference
2.0 Mtons
*** (p<0.05)
NS
NS
NS
NS
Average of all Soils collected
20 Mton acre-1
70 Mton acre-1
120 Mton acre-1
150 Mton acre-1
38 Mton acre-1