Impact of carbon sequestration On

soil and crop productivity

Pravash Chandra MoharanaRoll no. 4805

Division of Soil Science & Agricultural ChemistryIndian Agricultural Research Institute

New Delhi-110 012

Global warming

Top Ten CO2 Producing Nations

1. USA

2. China

3. Russia

4. Japan

5. India

6. Germany

7. Britain

8. Canada

9. South Korea

10.Ukraine

IPCC,2001

Greenhouse gases

Gas Concentration in 1985

Annual increase since 1985 to present (%)

Contribution to global warming (%)

CO2 345 ppm* 0.5 50

CH4 90ppb 0.8 19

N2O 1.65 ppm 1.0 5

CFC 0.24 ppb 3.0 15Others ---------- ----------- 11

*Present level 386 ppmIPCC,2001

Carbon Loss in India and

World

Atmosphere 748 Gt

Fossil fuels 4000 Gt

Terrestrial 2000 Gt

Soil 1550 Gt

Biota 450 Gt

Oceans 38, 000 Gt

Lal et al., 2004

World Carbon Pool

SOIL1550 Pg C

BIOTA600 Pg C

ATMOSPHERE750 Pg C

100 Pg/yr

80 Pg

/yr

80 Pg/yr

100 Pg/yr

Respiration

Photosynthesis

Humus

Soil r

espi

ratio

n

and

deco

mpo

sition

Role of soil in C cycling

Lal and Kimble., 1997

Organic carbon pool in soils of India and the world

Lal, 2004

Depletion of soil organic carbon concentration of cultivated compared with that in undisturbed soils

Lal, 2004

Total soil erosion in India

Yadav, 1996

Soil erosion and C emission in India

Processes Flux

Total soil erosion 2.98 Pg sediments/yr (2979 Tg sediments/yr)

Total C loss at 8–12 g/kg 23.8–35.8 Tg C/yr

C emission at 20% of displaced C

4.8–7.2 Tg C/yr

Lal, 2004

Total potential of carbon sequestration in soils of India

World : 600 – 1200 Tg C/y

Lal, 2004

Carbon Sequestration

Lal,1995

It refers to the provision of long-term storage of carbon in the terrestrial biosphere, underground, or the oceans so that the buildup of carbon dioxide (the principal greenhouse gas) concentration in the atmosphere will reduce or slow down

Soil Carbon Sequestration

Atm osphericCO 2

Plantrespiration

Anim alrespiration

Soil respiration

Photosynthesis

Soilorganism s

Soilorganicm atter

D issolvedCO

in water2

Leachate

A tm osphericN 2

M ineralization

Denitrification

B iologicalN fixation

Carbonatem inerals

Fossil fue ls

CO 2

NN ON

2

2

O

NHvolatilization

3

NHfixation

4

Plantuptake

Fertilizer

CarbonInput

CarbonOutput

SoilCarbon

Sequestration

Soil CSoil C

X

Decomposition/Mineralization ControlsAbioticSubstrate AttributesNutrient AvailabilitySoil DisturbanceDecomposer Community

CO2, CH4

DOC

Residue, Roots, Manure Compost CO2

Soil acts as a source as well as sink of atmospheric CO2Soil acts as a source as well as sink of atmospheric CO2

Soil Microbial ActivitySoil Microbial ActivitySoil Organic Matter (C)Soil Organic Matter (C)

CO2CO2

Harvestable YieldHarvestable Yield

SunlightSunlight

ClimateClimate

SoilsSoils ManagementManagement

C cycle in agricultural ecosystem

Soil carbon trajectories

CO2 EMISSIONS vs. CARBON SEQUESTRATION

Current loss of organic carbon to the atmosphere as CO2 is 3.2 Pg/yr.

if all the degraded agricultural lands of the world (2 billion hectares or 2x 109 ha) having a bulk density of 1.5 Mg/m3 sequester OC @ 0.01%/yr, then the carbon sequestered will be 3.0 Pg/yr, which is just close to the SOC emitted to the atmosphere and can offset the entire green house effect[ (2x 109 ha) x (104 ha/m2) x (1m) x (1.5 Mg/m3) x (10-

4/yr) = 3.0 Pg/yr]

Lal et al.,1999

Depletion : Cinput < Coutput

Sequestration: Cinput > Coutput

Soil Processes Conducive to the Enhanced Carbon Storage

1.Aggregation: Increase in stable micro-aggregates through formation of organo-mineral complexes

encapsulates C and protects it against microbial activities.

2.Humification: To sequester 10,000 kg of C in humus, 833 kg of N, 200 kg of P and 143 kg of S are needed

3.Translocation into the Sub-Soil: Translocation of SOC into the sub-soil.

4.Formation of Secondary Carbonates: 5.Burial of SOC-Laden Sediments: Transport of SOC-enriched sediments to depressional sites and/or aquatic ecosystems

6.Plantation of Deep-Rooted Plants

Technological options for C sequestration in soil and biota

Lal., 2004

Recommended Management Practices and C sequestration potential

Recommended practices C sequestration potential(Mg C/ha/yr)

Conservation tillage 0.10-0.40

Winter cover crop 0.05-0.20

Soil fertility management 0.05-0.10

Elimination of summer fallow 0.05-0.20

Forages based rotation 0.05-0.20

Use of improved varieties 0.05-0.10

Organic amendments 0.20-0.30

Lal et al., 1998

Minimal disturbance of the soil surface is critical in avoiding soil organic matter loss from erosion and microbial decomposition.

Conservation-Tillage

Jat, 2006

Tillage effects on SOC and MBC after four crop cycles of Rice-Wheat System

Winter crops Forage in rotation Growing legume crops Eliminate fallow Deep rooted crops

Legumes can fix up to 60-100 kg of N/ha annually, depending on the species and soil type. For each legume crop grown, approximately 1 ton of CO2 –C emission is avoided. There is also increased plant residue input and increased soil organic carbon content.

Intensification of cropping system

Carbon pools of subhumid, semiarid tropical and arid ecosystems under different cropping system

Swarup et al., 2000

Intensification of cropping system and crop rotation and fertilization effects on organic C in soil

Soil organic carbon (SOC), changes in SOC and carbon sequestration rate in 0-45 cm soil in a long-term fertilizer experiment under maize-wheat-cowpea cropping system

Purakayastha et al., 2008

Integrated nutrient management

Plant roots and carbon sequestration

Plant root acts as a medium for transfer of atmospheric carbon into the soil Root lysis and root exudates contribute significant quantities of carbon deposited in sub-surface soil

Treatments Avg. annual root biomass yield (Mg/ha/yr)

Estimated return of carbon (Mg/ha/yr)

50% NPK 4.80 2.16

100% NPK 5.47 2.46

150% NPK 6.05 2.72

100% NP 4.94 2.24

100% N 4.63 2.09

100% NPK+FYM 6.27 8.07

Control 2.95 1.33

Root biomass carbon

Purakayastha et al., 2008

Tree plantingsConservation-tillage croppingAnimal manure applicationGreen-manure cropping systemsImproved grassland managementCropland-grazingland rotationsOptimal fertilization

Management of Land Degradation

Organic carbon content in soil after six years under different land uses

Land use Organic C (%)0-15 cm 15-30 cm

Sole cropping 0.42 0.37Agro forestry 0.71 0.73Agro-horticulture 0.73 0.74Agro-silviculture 0.38 0.56

Das et al., 1994

Degradation of permanent grasslands can occur from accelerated soil erosion, compaction, drought, and salinization

Strategies to sequester carbon in soil should improve quality of grasslands

Strategies for restoration should include:

Improved Grassland Management

Enhancing soil cover Improving soil structure to

minimize water runoff and soil erosion

Improved Grassland Management

Franzluebbers et al., 2001

Years of Management

0 1 2 3 4 5 6 7 8

SoilOrganicCarbon

(Mg . ha-1)

12

14

16

18

20

22

24

Cut for hay

Years of Management

0 1 2 3 4 5 6 7 8

SoilOrganicCarbon

(Mg . ha-1)

12

14

16

18

20

22

24

Cut for hay

Unharvested

Years of Management

0 1 2 3 4 5 6 7 8

SoilOrganicCarbon

(Mg . ha-1)

12

14

16

18

20

22

24

Unharvested

Cut for hay

Lowgrazing pressure

Years of Management

0 1 2 3 4 5 6 7 8

SoilOrganicCarbon

(Mg . ha-1)

12

14

16

18

20

22

24

Unharvested

Cut for hay

Lowgrazing pressure

Highgrazing

pressure

Soil organic carbon sequestration rate (Mg ha-1 yr-1) (0-5 yr):--------------------------------

Hayed 0.30Unharvested 0.65Grazed 1.40

C sequestration impact on soil

and crop

Crop yield and productivity effects of SOC pool

SOC Pool

Crop

Yie

ld Unfertilized

Fertilized

SOC Pool

∆ Yi

eld

SOC Pool

Soil

Qua

lity

Microbial biomass

Nutrient Retention

Available water capacity

Aggregation

Infiltration rate

Aeration porosity

Agronomic productivity

WUENUE

Soil Quality and SOC Pool

Role of SOM in Soil and Plant Health

Haynes and Naidu., 1998

Role of SOM in Soil and Plant Health

Water retention Soil temperature and aeration Chelation Cation exchange Mineralization of nutrients Buffer action

Plant C

SOM SOM

CO2 CO2

FungiFungi

Micro-aggregates

No-Till = Lower disturbance

Soil MacroaggregateSoil Macroaggregate

Tillage = Higher disturbance

Plant C

SOM SOM

CO2 CO2

FungiFungi

Micro-aggregates

No-Till = Lower disturbance

Soil MacroaggregateSoil Macroaggregate

Tillage = Higher disturbance

Plant C

SOM SOM

CO2 CO2

FungiFungi

Micro-aggregates

No-Till = Lower disturbance

Soil MacroaggregateSoil Macroaggregate

Tillage = Higher disturbance

White and Rice, 2007

Soil aggregate formation

Effect of soil management systems on soil properties in the top layer of 0-7.5 cm

Properties Conventional Integrated Organic

OC (g/kg) 5.59 7.16 9.41

Bulk density (Mg/m3)

1.18 1.12 0.93

Aggregate stability (%)

10.6 22.8 13.5

Nitrate N (kg/ha)

12.5 20.3 7.9

Extractable P (kg/ha)

41.8 52.3 45.7

Earthworms (number/m2)

35 212 106

Glover et al., 2000

Microbial BiomassMicrobial biomass is positively correlated to an estimate of the organic N available to crops in no-tillage surface soil.

1 to 5% of SOC is in microbial biomass and 2 to 6% of soil organic N.

Microbial biomass represents a significant amount of potentially mineralizable N.

Microorganisms produce:Plant growth hormonesStimulate plant growth

hormonesCompete with disease

organisms

Treatments

Total C (g/kg)

Bulk densityg/cm

Microbial biomass (mg/kg)

OM 9.41 1.20 135.8

1/2OMN 7.16 1.26 98.7

NPK 5.59 1.29 74.4

NP 5.21 1.30 65.5

PK 4.85 1.32 55.8

NK 4.23 1.35 46.8

C 3.92 1.40 41.7

Physical and biological properties influence by OM(from 1990 to 2007)

Gong et al., 2008

Response of soil organic C in different particle size fractions

Majumder et al., 2007

Crop Area (Mha)

Current yield (kg/ha/yr)

Projected increase kg/ha/yr/ Mg of SOC

Total increase in production 106 Mg/yr

Barley 0.76 1800 20-50 0.02-0.03

Beans 9.0 400 30-50 0.3-0.5

Wheat 27.3 2640 30-50 0.8-1.4

Rice 42.5 2927 30-50 1.3 – 2.1

Maize 14.0 670 100-300 1.4 – 4.2

Sorghum

9.2 700 100-140 0.9 – 1.3

Total 6.9 – 12.5

Soil carbon sequestration and yield increase of principal crops in India

Lal., 2005

Treatments Total C (g/kg) Wheat yieldKg/ha/yr

Maize yieldKg/ha/yr

OM 9.41 3436 5994

1/2OMN 7.16 4484 6811

NPK 5.59 4609 6922

NP 5.21 4415 6544

PK 4.85 1078 1481

NK 4.23 594 870

C 3.92 568 766

Crop yield under different soil organic carbon (from 1990 to 2007)

Gong et al., 2008

Year Zero tillage+residue Zero tillage- residue

1996 4000 2800

1997 6200 2100

1998 5000 3000

1999 1800 1700

2000 6000 4800

2001 6200 1500

2002 6500 2000

Comparison of rainfed maize yield (kg/ha) on different tillage and residue management

practices

Thomas, 2009

Years

Yields variation of jute and soybean with SOC of the treatments

Manna et al., 2005

Conclusion

Judicious application of bulky organic manures and balanced fertilization , reduce tillage and forage and legumes helps in restoring the organic carbon status of soil

Cultivation of fast growing trees with arable crops under agro-

forestry systems such as agrohorticulture or agro-silviculture systems helps in improving soil organic carbon content

SOC helps in improving physical, biological, chemical properties soil and also improving crop productivity in long term basis.

Future steps

Standardised methodologies for estimating above and below-ground C stocks to improve the reliability of data

Prediction of models to accommodate future climate ,land-use changes, crop production and their implications for CO2 mitigation

Save soil Save life….

…Thank you