Soil Carbon Sequestration Long-Term Effets of Tillage and Crop

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Transcript Soil Carbon Sequestration Long-Term Effets of Tillage and Crop

Soil Carbon Sequestration:
Long-term Effect of Tillage and Rotations
Charles W. Rice
and
Karina Fabrizzi
Kansas State University
October 28-30, 2008
1
Global economic mitigation potential for
different sectors at different carbon prices
7
GtCO 2-eq
6
5
4
3
2
Non-OECD/EIT
EIT
OECD
World total
1
Energy supply
0
00
US$/tCO2-eq
<1
<5
0
<2
0
00
<1
<5
<2
0
0
Transport
Buildings
Industry
Agriculture
Forestry
Waste
IPCC, 2007
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
Agriculture
• Cropland
– Reduced tillage
– Rotations
– Cover crops
– Fertility management
– Erosion control
– Irrigation management
• Rice paddies
– Irrigation
– Chemical and organic fertilizer
– Plant residue management
Rice fields in The
Philippines
• Agroforestry
– Improved
management
of trees and
cropland
No-till seeding in USA
Maize / coffee fields in
Mexico
Agricultural Management Strategies
for C Sequestration
Develop Agricultural Management Programs that:
Enhance C Inputs
Reduce C losses
 Crop Management
 Tillage
 Crop Selection
 Fallow Management
 Crop Rotations
Climate
Sunlight
Soils
Management
CO2
Harvestable
Yield
Soil Microbial Activity
Soil Organic Matter (C)
Potential C sequestration in U.S
Strategies
Decreasing tillage intensity
Mg C ha-1 yr-1
Management practices
Reduced tillage, no-tillage, mulch
tillage
0.24-0.40
High residue crops, applications
of manure and biosolids, erosion
Increasing amount of crop
control, irrigation, integrated pest
residue return
management, precision
agriculture
Use of winter cover crops
0.1-0.3
Summer fallow elimination
0.1-0.3
Fertilizer management
Perennial vegetation
CRP
0.05-0.15
0.3-0.7
Lal et al., 1999, Post et al.,2004
Corn production in NE Kansas
• Continuous corn
• 168 kg N/ha
• Tillage Systems
– No-tillage
– Conservation tillage (Chisel-disk)
• 15 year analysis
8
Soil C stocks after 18 years
0-5
*
NT
CT
5-15
15-30
30-60
*
0-60
*
0
20
40
60
80
100
120
Nicoloso et al., 2008
9
Tillage effects on soil organic C by
depth, Minnesota: 14 y continuous corn
Mg C/ha/cm
Depth
No-till
Plow
0.7.5
4.49
3.89
7.5-15
4.94
4.66
15-30
3.51
3.17
30-45
2.45
1.48
**
0-45 (Mg/ha)
160
133
**
**
Huggins et al., 2007
10
-1)
SOC levels (Mg C ha
E
O
A
Change in management
Years of cultivation
Soil C sequestration rates for 15 years
(Mg C/ha/y)
Depth
Fertilizer N Fertilizer N
Tilled
No-till
Manure N
Tilled
Manure N
No-till
cm
0-5
0-15
0.161
0.254
0.351
0.497
0.393
0.792
1.182
1.402
0-30
0.336
0.717
0.839
1.387
0-60
0.146
1.325
0.733
1.141
• NT > Tilled, but tilled had some increase
• Added C (manure) is less conserved in tilled
• What is baseline?
Nicoloso et al., 2008
12
-1)
SOC levels (Mg C ha
E
D
O
C
A
Change in management
Years of cultivation
Net effect of NT for 15 years
NT (0-15y) –T (0-15y)
Depth
No N
0.5
Fertilizer N
cm
0.5
Fertilizer N Manure N
Manure N
Mg/ha/y
0-5
0-15
0.187
0.182
0.450
0.371
0.190
0.243
0.468
0.402
0.789
0.610
0-30
0.174
0.311
0.381
0.417
0.548
0-60
-0.443
-0.191
1.179
0.961
0.408
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)
Location
Rotation
Duration
CT
RT
NT
Hayes
Wheat-Sorg-F
37 y
0.008
0.020
0.055
Parson
Sorg-Soy
20 y
0.234
0.370
0.420
Ashland
Average
29 y
0.269
0.346
0.384
Tribune
Wheat-Sorg-F
15 y
-0.570 -0.503 -0.392
Fabrizzi, 2006
15
SOC using NT or RT (Mg C ha-1 ) at 0-30 cm
60
SOCNT = 1.14x - 4.90
R2 = 0.76
55
1:1 Line
SOCRT =1.08x - 3.14
R2 = 0.67
50
45
40
Ashland RT
Parsons NT
Parsons RT
Hays NT
35
Ashland NT
Tribune RT
Tribune NT
Hays RT
30
30
35
40
45
50
55
60
SOC using CT (Mg C ha-1) at 0-30 cm
Intergovernmental Panel on Climate Change (IPCC): 1.1 for CT to NT
16
West and Post (2002): 1.16 for CT to NT
Fabrizzi, 20064/3/2016
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
Rotation
Duration
0N
22 N
45 N
67 N
Wheat-Sorg-F
37 y
0.007
0.012
0.035
0.057
Fabrizzi, 2006
17
Carbon sequestration rate (C rate) expressed in equivalent mass
(Mg C/ha/y) to a 30 cm depth for Manhattan, KS USA
Rotation
Continuous Soybean
0.066
Continuous Sorghum
0.292
Continuous Wheat
0.487
Soybean - Wheat
0.510
Soybean - Sorghum
0.311
Fabrizzi, 2006
18
Conservation of Soil Carbon
H2O
O2
Plant
characteristics
Microbial composition
and activity
Hierarchy of importance
Temperature
Organic C
Substrate
quality
Clay
Biological
factors
Physical Protection
Disturbance
Organics
Mineralogy
Clay
Chemical
CO2
• Fungal Role (18:2w6 biomarker)
• Significant tillage X residue
interaction (p<0.05)
0.08
Mole Fraction
a
0.06
b
c
0.04
c*
0.02
0
CT + No R
CT + Residue
NT + No R
NT + Residue
Frey et al. (1999) found greater fungal networks optically
in NT as compared to CT for the same soil.
White and Rice, 2007
Tillage = Higher
disturbance
CO2
No-Till = Lower
disturbance
CO2
Plant C
Fungi
Fungi
Microaggregates
SOM
Soil Macroaggregate
White and Rice, 2007
SOM
Soil Macroaggregate
80
YMollisol = 1.48 SOC - 8.2
R2 = 0.9245
60
(g 100g -1 soil)
Amount of macroaggregates
70
YVertisol = 1.56 SOC - 2.83
50
R2 = 0.1292
40
30
20
YOxisol = 0.58 SOC - 6.9
10
R2 = 0.3344
0
0
10
20
30
40
-1
SOC (g C kg )
Fabrizzi, 2006
50
60
70
Gaseous
Emissions
Environmental
Services
Microbial
Activity
Soil
Structure
Water
Soil
Biodiversity
Soil
Organic
Carbon
Nutrient
Cycling
Erosion
&
Availability
Plant Growth
Yield
Sustainability
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
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
Chuck Rice
Phone: 785-532-7217
Cell: 785-587-7215
[email protected]
• Websites
www.soilcarboncenter.k-state.edu/
K-State Research and Extension
Treatment
Rate
(Mg C/ha/y)
State
0.073
0.117
0.229
Eastern
Colorado
NT (corn) NT 150 N Fert
0.80
NE
Kansas
Rotations
0.764
0.605
0.624
SC KS
0.80
NE
Eliminate
summer
fallow
CRP
Scenario
3-year system
4-year system
Continuous
cropping
CT - NT wheat
CT - NT sorghum
CTsorg/NTwheat
to NT sorg/wheat
27
4/3/2016