Soil organic carbon stocks/sequestratiion and ...

World Soil Issues and Sustainable Development: An agenda for Action 40 years ISRIC – World Soil Information (Anniversary Seminar, 9th March 2006, Wageningen)

Soil Organic Carbon Stocks/Sequestration and Greenhouse Gas Emissions Carlos C. Cerri, Carlos E. P. Cerri, David Powlson, Niels H. Batjes, Martial Bernoux, Keith Paustian, Eleanor Milne, Charles W. Rice

Soil Organic Carbon Stocks/Sequestration and Greenhouse Gas (GHG) Emissions

TOPICS General Considerations Importance of soil organic carbon Carbon balance and sequestration The tropics Carbon sequestration and international effort

Soil Organic Carbon / GHGs in the tropics Known knows Known unknowns Unknown unknowns

Final Considerations





Soil Organic Carbon Stocks/Sequestration and Greenhouse Gas Emissions

Importance of SOC at global scale

Emissions

Atmosphere

Pg 730 +

Vegetation

470-655

Soil (0-30cm)

~700

Soil (1m)

1500-2000

Values in Gt C (1Gt = 109 t = 1 Pg)


Emissions

Importance of SOC at global scale Atmosphere

Pg 730

Vegetation

470-655

Soil (0-30cm)

~700

Soil (1m)

1500-2000



Importance of SOC at global scale

Sequestration

Emissions

Atmosphere

Pg 730 -

Vegetation

470-655

Soil (0-30cm)

~700

Soil (1m)

1500-2000



Importance of LULUCF to the radiative forcing Radiative forcings* by main sector Agriculture

20%

66% Industries cement And Fuel IPCC-SAR, 1996

Land Use Change

14%

* Change in the energetic balance of the Earth


Importance of LULUCF to the radiative forcing Radiative forcings* by main sector 1.4 ± 0.2

Agriculture Agriculture

W.m-2

20% CO20% 5%

0.7 ± 0.2 0.15 ± 0.05

CO2

CH4

2

CH4 50% N2O 70%

N2O

66% Industries cement And Fuel IPCC-SAR, 1996

Land Use Change Land Use Change

14% 14%

CO2 17% CH4 5% N2O 10% * Change in the energetic balance of the Earth


Importance of LULUCF to the radiative forcing Radiative forcings* by main sector 1.4 ± 0.2

Agriculture Agriculture

W.m-2

20% CO20% 5%

0.7 ± 0.2 0.15 ± 0.05

CO2

CH4

2

N2O

LULUCF CO2 22% CH4 55% N2O 80% IPCC-SAR, 1996

CH4 50% N2O 70% Land UseChange Change Land Land Use Use Change

14% 14%

CO2 17% CH4 5% N2O 10%

* Change in the energetic balance of the Earth


Carbon Balance at the plot scale ∆C plant (aerial)

CO2

∆C plant (root) ∆C litter ∆C soil ∆C soluble ∆C particulate

C soluble C particulate

Time Old System t.0

New System


LULUCF

Carbon Sequestration at the plot scale

CO2 22% CH4 55% N2O 80%

It must be computed all 3 gases and reported using the same equivalent

Global Warming Potential (GWP)

CO2

CH4

N2O

1

23

296

CO2 Equivalent 1 kg CH4 = 23 kg CO2eq 1 kg N2O = 296 kg CO2eq C Equivalent 1 kg C-CH4 = 8.4 kg Ceq 1 kg N-N2O = 126.9 kg Ceq

Soil Organic Carbon Stocks/Sequestration and Greenhouse Gas Emissions LULUCF

CO2 22% CH4 55% N2O 80%

C sequestration ≠ C balance

∆C plant (aerial)

CH4

N 2O

CO2

∆C plant (root) ∆C litter ∆C soil ∆C soluble ∆C particulate

C soluble

∆C gases (CH4, N2O)

C particulate

Time Old System t.0

New System

Versus Alternative system


The Tropics Rates of land use change is greatest in the tropics Feed 70% of the population (Lal and Sanchez 1992) Increasing demand for land will be met by converting forest and pasture (C release) ~ 26% of global SOC stocks are in the tropics (Batjes 1996) Relatively little information on soils and how they react to land use change


Carbon sequestration and international effort ¾ The Kyoto Protocol - CO2 emissions can be offset against carbon removal from the atmosphere ¾ 1st commitment period: 2008 – 2012 ¾ Article 3.3: forestry activities ¾ Article 3.4: management of agricultural soils ¾ Changes before 2008? ¾ UNFCCC -Inventories of CO2 emissions from LUC ¾ Soils sources/sinks C?


Carbon sequestration and international effort

Kyoto Protocol

We need more scientific knowledge






Known Knowns ?

Tropical Soils ? Known Unknowns

? Unknown Unknowns

Soil Organic Carbon Stocks/Sequestration and Greenhouse Gas Emissions Global distribution of soil organic carbon: native condition

? Known knowns

Global soil organic carbon ~ 1500 Pg

0-100 cm WRI, 2000 (FAO, 1995 & Batjes, 1996)


? Known knowns

Global soil organic carbon ~ 700 Pg

Tropical ecosystems ~ 26% or 180 Pg

0-30 cm WRI, 2000 (FAO, 1995 & Batjes, 1996)

Soil Organic Carbon Stocks/Sequestration and Greenhouse Gas Emissions Decline in SOM

?

Known knowns

GHG emissions

GHG CO2 N2O CH4

Carbon inputs and SOM decomposition rates are higher in the humid tropics

Soil Carbon stock Remaining from native vegetation DEFORESTATION

Time

Soil Organic Carbon Stocks/Sequestration ? and Greenhouse Gas Emissions Sources of GHG emissions Known knowns

Agriculture and land use change Fossil fuel combustion

Global

G H G (%)

Brazil

22 55 80

CO2 CH4 N2 O

75c 91 94

78%

25%

Global ranking GHG in Brazil

Fossil fuel combustion

Only fossil fuel combustion:

17th

Fossil fuel combustion + Agriculture and land use change

5th

Soil Organic Carbon Stocks/Sequestration and Greenhouse Gas Emissions Soil carbon modelling

Survey data

?

Known knowns

CARBON SEQUESTRATION RURAL APPRAISAL

CURRENT LAND USE INFORMATION FROM LOCAL KNOWLEDGE (SHEET A) STATE

COUNTY

INDIANA

BLACKFORD

FOR INDICATED SOILS ON MAP DETERMINE: MUID (STATSGO ASSOCIATION) IN004 IN005 LAND USE INFORMATION TOTAL CROPLAND

72.9

90.7

IN029

IN032

74 83.4 CARBON SEQUESTRATION RURAL APPRAISAL

CLASS I & II CLASS III & IVGENERAL

LAND USE INFORMATION FROM LOCAL KNOWLEDGE (SHEET B)

Dynamic soil C modelling tool

CLASS V & VI FOREST OR TREES STATE GRASS LANDS

10.9

0.9 INDIANA

14

7.7

8.5

3.1

99.9%

100.0%

100.0%

100.1%

17.5

COUNTY

11.9

BLACKFORD

CARBON SEQUESTRATION RURAL APPRAISAL 0.6 THE COUNTY 0 1.7 ANY 0.1 PART OF BEEN DRAINED (YES/NO): IF YES, ANSWER THE FOLLOWING. 2 0.05 0 GENERAL 0 LAND USE INFORMATION FROM LOCAL KNOWLEDGE (SHEET C)

WATER / WETLANDS HAS URBAN / OTHER TOTAL

ROLLING HILLS

IN004

FLOOD PLAIN

IN005

OTHER TOTAL

IN029

0.0%

OPEN DITCH DRAINAGE INDIANA STATE % OF SOIL TIME PERIOD OF DRAINED INSTALLATION IS 10% OR MORE OF ANY MUID

LANDSCAPE DESCRIPTION MUID FLAT

STEEP HILLS

0.0%

0.0%

0.0%

0.0%

0.0%

COUNTY LEVEL FARMING AND CROPPING SYSTEM HISTORY FROM PRE 1900 TO PRESENT (SHEET D) STATE

MUID

0.0%

0.0%

TILE DRAINAGE BLACKFORD % OF SOIL TIME PERIOD OF CARBON SEQUESTRATION RURAL APPRAISAL DRAINED

COUNTY

INSTALLATION IRRIGATED (YES/NO):

IF YES, ANSWER THE FOLLOWING.

0.0%

0.0%

COUNTY

INDIANA

TIME PERIOD OF % OF SOIL ANNUAL AMOUNT 1970-1990+ TIME FRAME INSTALLATION IRRIGATED APPLIED (INCHES) 0.0% 0.0% 0.0% 0.0% 0.0% 0.0%

BLACKFORD

TYPES OF SYSTEMS

ANNUAL CONSERVATION PRACTICES INSTALLED

IN004 PRACTICES INSTALLED 85% BY COUNTY AND SOIL TYPE IN032 % ESTIMATE OF COUNTY BEING FARMED DURING THIS TIME FRAME: TOTAL CROPLAND: % OF THIS SOIL IDENTIFIED AS CROPLAND . THE SUM OF LAND CAPABILITY CLASS I & II, III & IV, AND V & VI MUST ADD TO THIS %. CLASS I & II: % OF THIS SOIL THAT IS CLASS I & II CROPLAND. CLASS III & IV: % OF THIS SOIL THAT IS CLASS III & IV CROPLAND. CLASS V & VI: % OF THIS SOIL THAT IS CLASS V & VI CROPLAND. FOREST OR TREES: % OF THIS SOIL IDENTIFIED AS FOREST OR TREES.

IN005 IN029 IN032

USE IN REPORTING TO DOE FOR CARBON SEQUESTRATION (USE SEPARATE SHEET FOR EACH SOIL MUID)

CROP ROTATIONS (SPECIFY 1 TO 3) 1)

GRASS LANDS: % OF THIS SOIL IDENTIFIED AS GRASS LANDS.

2)

WATER / WETLANDS: % OF THIS SOIL IDENTIFIED AS WETLANDS.

3)

CORN-SOYBEAN

STATE INDIANA

LANDSCAPE DESCRIPTION: % OF THIS SOIL IN EACH LANDSCAPE DESCRIPTION.

FOR INDICATED CROPS CROP NAME YIELD (BU OR TONS/AC)

COUNTY

BLACKFORD

MUID

ACRES OF CONSERVATION PRACTICES INSTALLED (ACRES) GRASS TREE COMMON CROP ROTATION (s) CONVERSIONS PLANTING

URBAN / OTHER LANDS: % OF THIS SOIL IDENTIFIED AS OTHER LANDS INCLUDING URBAN LANDS, DEVELOPED LANDS, ABANDONED LANDS.

CORN

SOYBEAN

130

40

REDUCED TILLLAGE

NO-TILL

REDUCED TILLLAGE

NO-TILL

IN004

WETLANDS CREATED AND/OR RESTORED

1985 1986

N FERT APPLIED (LBS/AC)

110 1987

MANURE APPLIED (TONS/AC)

2

1988

1989 MUID: SOIL MAP UNIT ID FROM STATSGO. (FROM MAP) DISK DISK TYPICAL TILLAGE OPERATIONS MUID: SOIL MA P UNIT ID FROM STA TSGO. (FROM MAP) TIME PERIOD OF INSTALLATION:TIME GIVE THE TIME PERIOD WHEN DRAINAGE PRACTICES 1990 PERIOD OF INSTALLATION: GIVE THE TIME PERIOD WHEN IRRIGA TION PRA CTICES WERE INSTALLLED. (i.e. 1930-1950, 1940-1960, 1970CULTIVATE DISK WERE INSTALLLED. (i.e. 1930-1950, 1940-1960, 1970-1990, ETC.) 1990, ETC.) 1991

PLANT

% OF SOIL IRRIGATED: GIV E A OF N ESTIMA TE FOR THESE OF THEINSTALLED. AMOUNT OF IRRIGATION INSTALLED. % OF SOIL DRAINED: GIVE AN ESTIMATE FOR THESE SOILS THE AMOUNT OF SOILS DRIANAGE

PLANT

1992 CULTIVATE ANNUAL AM OUNT APPLIED (INCHES): GIVE AN ESTIMATE OF THE ANNUAL AMOUNTCULTIVATE OF IRRIGATION WATER APPLIED IN INCHES. (6 INCHES, 12 1993 INCHES, 15 INCHES, ETC.) 1994 TYPES OF SYSTEMS: TYPICAL TYPE OF IRRIGATION SY STEM INSTALLED. (CENTER PIVOT, GATED PIPE, ETC.)

Input database

1995

Comments:

1996 1997 1998

TIM E FRAM E: PERIOD OF TIME AS SPECIFIED. 1999 % ESTIM ATE OF COUNTY BEING FARM ED DURING THIS TIM E FRAM E: GIVE AN ESTIMATE OF THE COUNTY AREA BEING FARMED DURING THIS TIME FRAME. 2000

Simulation models

Output database

TYPICAL CROP ROTATION: CROP ROTATIONS INCLUDE (CORN-CORN; CORN-SOYBEAN; CORN-CORN-OATS-MEADOW-MEADOW; M UID: SOIL MAP UNIT ID FROM STATSGO. (FROM MAP) CORN-SOYBEAN-CORN-OATS-MEADOW-MEADOW; ETC) CROPROTATIONS. ROTATION: PICK THE TWO MOST COMMON CROP ROTATIONS. IF ONE ROTATION IS >90% OF CROPPED ACRES, FOR INDICATED CROPS: ACTUAL CROP INFORMATION FOR THE INDICATED CROPS IN THE REPORT ONLY THAT ROTATION. TOTAL FOR THE COUNTY SHOULD EQUAL THE CTIC REPORTED VALUES FROM 1989 TO CROP: CROP NAME AS SHOWN IN CROP ROTATION. PRESENT. SEE SUPPLEMENTAL INFORMATION. YIELD: CROP YIELD IN BU/AC FOR GRAINS OR TONS/AC FOR HAY. REDUCED TILLAGE: REDUCED TILLAGE FARMING WHICH LEAVE GREATER THAN 15% RESIDUE AFTER PLANTING. (INCLUDES N FERT APPLIED: ESTIMATE OF COMMERCIAL NITROGEN FERTILIZER APPLIED ANNUALLY (LBS/AC). MULCH TILL, RIDGE TILL BUT NOT NO-TILL).

MANURE APPLIED: ESTIMATE OF MANURE APPLIED ANNUALLY (TONS/AC), BY CROP.NO-TILL: NO-TILL FARMING SYSTEM. TYPICAL TILLAGE OPERATIONS: TYPICAL TILLAGE OPERATIONS USED TO GROW THIS CROP. (EXAMPLES ARE FALL PLOW; GRASS CONVERSIONS: ALL GRASS PLANTING CONSERVATION PRACTICES. SPRING PLOW; CHIESEL PLOW; DISK; HARROW; CULTIVATOR; DRILL; PLANT; ETC.)

(WATERWAYS, BUFFERS INCLUDING RIPIARIAN BUFFERS, FILTER STRIPS, TERRACES, CRP). USE 12' WIDTH FOR TERRACES (LF*12/43560=ACRE). USE 40' WIDTH FOR ALL OTHER PRACTICES REPORTED IN LINEAR FEET (LF*40/43560=ACRE). TREE PLANTING: ALL CONSERVATION PRACTICES THAT INCLUDE TREE PLANTINGS. (WINDBREAKS, SHELTERBELTS, AGROFORESTRY)

Plant Growth

WETLANDS CREATED AND/OR RESTORED: ALL CONSERVATION PRACTICES THAT INCLUDE THE CREATION OR RESTORATION OF WETLANDS.

Spatial data

Residues CO2

CO2

Active SOM

CO2

CO2

Slow SOM

Passive SOM CO2 CO2

90 80

No-tillage

70

Conventional tillage

60 50 40

Process-knowledge

30 20 10

n B K e e nd nt uc Ke ky nt W u . L cky a S . fay Ch et t e ar le s Ho t on yt ev Ho i ll e yt ev Ho i ll e yt ev M i a n ll e ha tt W an oo st W er oo st W er oo st W er oo st er KB S Ak ro n Si dn ey

rif fi

e

ho

es rs Ho

G

G

rif fi

n

0

Long-term experiments

After: Easter et al. (2005)


?

Known knowns • Estimates of soil organic carbon (SOC) stocks for the Brazilian Amazon obtained from different studies (Cerri et al. 2006, AEE subm.) Source

Soil layer (cm)

SOC stocks (Pg)

Moraes et al. (1995)

0-20

21

Batjes & Dijshoorn (1999)

0-30

25

Bernoux et al. (2002)

0-30

22.7 ± 2.3

Batjes (2005)

0-30

23.9 - 24.2

GEFSOC project* Century RothC IPCC

0-20 0-20 0-30

32.6 27.0 26.9

* Estimates for the year 2000 and includes land use changes and management practices

• Estimates of SOC stocks and changes remain fraught with uncertainty, irrespective of scale. This uncertainty should be quantified (Falloon and Smith, 2003).


?

Known knowns food

fiber

Soil

biomass


energy

Soil

?

Known knowns


energy Ethanol sugarcane

?

Known knowns Biodiesel

soybean

Castor-oil plant

Soil Organic Carbon Stocks/Sequestration and Greenhouse Gas Emissions Global warming

?

Known knowns

CO2 Fotosynthesis


?

Known knowns

Biodiesel and the Carbon Cycle

Used or Waste Oil

Transesterfication Process

Oil Extraction and Use

CO2 in the Atmosphere Oil seed (ie. Canola)

Reduced Smog And CO2


?

Known knowns

CO2

+3,2 ± 0,1PgC yr-1

Preserving Biodiversity Combating land degradation

Improving soil quality Increasing soil productivity



?

Known knowns

win-win scenario

CO2

+3,2 ± 0,1PgC yr-1

Preserving biodiversity Combating land degradation

Improving soil quality Increasing soil productivity



biologically, it is most useful when it decays (Janzen 2006)

Emissions

Sequestration

Known knowns

Known knows….most known is

Soil organic matter is much more than a potential sink for storing excess CO2

?


biologically, it is most useful when it decays (Janzen 2006)

Emissions

Sequestration

Known knowns

Known knows….most known is

Soil organic matter is much more than a potential sink for storing excess CO2

?


Known Knowns ?


? Unknown Unknowns


?

Known Unknowns

Tropical ecosystems ~ 26% or 180 Pg

WRI, 2000 (FAO, 1995 & Batjes, 1996)


?

Known Unknowns

Soil C Known

Slash & burn

Crop/Pasture installation

?

Soil C

Unknown

Soil Organic Carbon Stocks/Sequestration and Greenhouse Gas Emissions Global distribution of soil organic carbon:

Organic carbon kg.m-2

anthropgenic use

180 Pg C

+∆ or

-∆

?

Known Unknowns

?

Soil Organic Carbon Stocks/Sequestration and Greenhouse Gas Emissions Carbon sequestration/GHG: full account

?

Known Unknowns

Example of N2O

100 Kg N ha-1 1.25 kg N-N2O 1 year

Soil C

Soil C

1.96 kg N2O x 296 (GWP) = 580 kg CO2eq

↓

158 kg Ceq ha-1 yr-1

∆ C > 158 kg ha-1 yr-1 to have a benefit N2O emissions can be greatly influenced by land management and difficult to predict

Soil Organic Carbon Stocks/Sequestration and Greenhouse Gas Emissions SOC origin

?

Known Unknowns

One origin

Soil Carbon stock Remaining from native ecosystem DEFORESTATION

Time


Known Unknowns

2

CO2

?

N 2O

Forest Slash Burn Dense Cerrado Cerrado In soil: Savanna Organic matter dynamic C and N stocks Agregation Structure δ 13C Functional diversity

CH4

Pasture

Agriculture

Main culture Soybean Rice Cotton Maize

Succession Fallow Millet Sorgum Pasture/crop

Management Conventional Conservative

Social and economic consequences

Population Income distribution Eduaction Health Sanitation


Known Knowns ?


? Unknown Unknowns


?

Unknown Unknowns

The most difficult part!!


?

Unknown Unknowns

Biotechnological improvement

Is it possible to enhance C sequestration by changing soil microorganisms, plant biochemistry and/or belowground allocation by plant? Do we know all about those??

Soil Organic Carbon Stocks/Sequestration and Greenhouse Gas Emissions Do we know all about plant??

?

Unknown Unknowns


?

Unknown Unknowns

Feedbacks Example

Plant and Soil

How will global warming, through its effects on carbon inputs (quantity and quality) and soil C mineralization, affect soil C stocks ?

Soil Organic Carbon Stocks/Sequestration and Greenhouse Gas Emissions Adding residue and N stimulated fungi which seemed to have Inhibited C mineralization……Why?

CO2

?

Unknown Unknowns

CO2

Plant C Fungi

SOM

Rice et al 2006

CT

NT

Fungi SOM Enhanced Aggregation


?

Unknown Unknowns

Food Security How will future “soil C sequestration/greenhouse gas emissions” impact on food security and livelihoods?






Knowledge of SOC stocks and changes is needed to devise plans for:

• The sustainable management of ecosystems •The mitigation of GHG emissions •The likely impacts of climate change on soils/ecosystems in the future


Our grandchildren still have problems to study…