The document discusses the critical role of soil organic carbon (SOC) in maintaining soil quality and health, particularly in the context of climate change and soil degradation in tropical regions, specifically India. It outlines the impacts of climate change on soil, the importance of SOC for agricultural productivity, and the management practices required to enhance carbon stocks in the soil. Additionally, it presents strategies for SOC sequestration and emphasizes the need for sustainable practices to improve soil health and meet agricultural demands.

1. By:
Bornali Borah
Ph.D. Scholar
Soil Science and Agril. Chemistry
Anand Agricultural University, Gujarat
Soil organic carbon – A key for sustainable
soil quality under scenario of climate change
1

2. Contents
Introduction
Impact of climate change on soil degradation
Role of SOC on soil health and quality
Management strategies to enhance carbon stock
in soil
Review of literature
Conclusion
Future line of work

3. Introduction
Priority action must be there to ensure that soils will cope worldwide
with these multiple and increasing demands
• is a key life supporting systemSoil
• SOUL OF SOILSoil organic carbon
• Intense rainfall and concurrent rise in
temperature with climate change
Tropical climate of
India
• soil health degradation
Depletion of soil
organic carbon
• Declining soil’s response to fertilizers,
• Widespread deficiencies of secondary &
micronutrients
Slowdown agricultural
productivity
• Adoption of appropriate Management
practices -essential prerequisite
Tropical regions
low C-sequestration rate
• A win –win option to “produce more from less”Soil C sequestration
1

4. 4
Fig.1: Contribution of SOC to the sustainable development goals
Maintaining SOC storage at an equilibrium or increasing SOC
content towards the optimal level for the local environment can
contribute to achieving the SDGs. (FAO,2017)

5. Static or Inherent soil
properties
 Mineral composition
 Soil texture
 Soil depth
Dynamic soil properties
 SOM
 Microbial biomass and diversity
 Soil respiration
 C and N mineralization
Soil quality is defined as the “fitness for use” and “capacity of the
soil to function” (Karlen et al. 1997).
Whereas, soil health presents the soil as a finite and dynamic living
soil resource, and is directly related to plant health.
 More specifically, soil health is defined as “capacity of soil to
function as a vital living system to sustain biological productivity,
maintain environment quality and promote plant, animal and
human health” (Doran and Zeiss 2000)
Soil Quality & Soil Health
5

6. Fig. 1. Soil attributes as indicators of soil health
(AWC = available water capacity; SOC = soil organic carbon; CEC = cation exchange capacity;
EC = electrical conductivity; MBC = microbial biomass; MRT = mean residence time). Source: Lal (2016)6

7. Soil degradation
 Soil degradation, characterized by decline in quality and decrease
in ecosystem goods and services, is a major constraint to
achieving the required increase in agricultural production.
 Predominant reasons of degradation of soil quality includes:
i) Erosion of topsoil and the SOC stock which decline soil fertility
ii) Intensive deep and inversion tillage which leads to
Rapid decomposition of crop residues, further accentuated by high
temperature
Disruption of stable soil aggregates and increasing oxidation of
entrapped SOC
Loss of microbial diversity of soil.
 Severe decline of SOC (0.1%) is the primary process causes
Secondary degradation (decline in soil aggregation & poor soil
tilth) which leads to Tertiary degradation (decline in soil structure,
water imbalances, loss of soil biodiversity and emission of GHGs)
7

8. Fig. 2: Processes, factors and causes of soil degradation 8

9. Fig. 3: Degradation of soil quality in relation to climate change
9

10. Fig 4:Spatial extrapolation of the temperature vulnerability of
soil C stocks.
a. Map of predicted changes in soil C stocks per pixel by 2050 under the ‘no
acclimatization’ scenario
b. Total reductions in the global C pool under 1 °C and 2 °C global average soil surface
warming by 2050, as expected under a full range of different soil C effect-time
scenarios (x axis)
Crowther et al. (2017)10

11. Fig. 5: Schematic diagram of dryland expansion due to climate change
and decrease in SOC.
Predictions include a growth in the land mass of dryland ecosystem by 11 to 23% before
the year 2100 Source: Huang et al. (2015)11

12. Depletion of
Organic C
pool in soils
Physical
degradation
Chemical
degradation
Biological
degradation
Ecological
degradation
Fig. 6:Interrelation of Soil degradation and depletion of organic carbon pools in soil
Emission of GHGs Physico-
chemical
degradation
Bio-chemical
degradation
Build up of
soil pest and
pathogens

13. Fig. 7: Sources and sinks of carbon from different pools under
terrestrial and aquatic ecosystems. Source: Mehra et al. (2018)

14. Soil Organic Carbon – A key indicator of Soil health
14

15. Soil carbon
SOIL ORGANIC CARBON
(SOC)
 Derived from the remains
of plants and animals
 more reactive
 highly dynamic and a
strong determinant of soil
quality (Chemical,
physical and biological)
SOIL INORGANIC CARBON
(SIC)
 Derived from the parent
material
 elemental C and
carbonate minerals (e.g.
calcite, dolomite,
aragonite and siderite).
15

16. Fig. 8. Types of organic and inorganic carbon pools in soil
Soil carbon
Soil inorganic Carbon (SIC)Soil organic Carbon (SOC)
SolidDissolved Dissolved
(bicarbonates)
Solid
(carbonates)
Unprotected
SOC
Protected
SOC
Contained in clay
& fine silt
Physical Chemical
Contained In
coarse silt & sand
EcologicalBiological
Contained within clay & fine silt
fractions
Leached into
shallow
ground water
Silicate: net
sequestration
Calcite:
no net
sequestration
Pedogenic
(secondary)
Lithogenic
(primary)
Ex-situ
(less
common)
In-situ
(more
common)
(SOC protection mechanisms)
0.01-1.0 Mg C ha-1y-1
0.5-75 kg C ha-1y-1 0.1-0.4 Mg C ha-1y-1
16

17. Role of SOC pools in relation to soil health
Effects of SOC C pools
Chemical fertility Microbial decomposition of SOC releases
nitrogen, phosphorus and a range of other
nutrients for use by plant roots.
Labile
&
slow
Provides available
nutrients to plants
Physical fertility
Microbial decomposed product (resins, gums,
polysaccharides etc.) that help bind soil
particles together into stable aggregates &
improved soil structure.
Improves soil
structure and
water holding
capacity
Biological fertility
Organic carbon is a food source for soil
organisms and micro-organisms.Provides food for
soil organisms
Buffers toxic
elements and
harmful
substances
SOC can lessen the effect of harmful
substances such as toxins and heavy metals by
sorption, and assist degradation of harmful
pesticides
Slow
and
recalcitrant
17

18. How much carbon can soil store?
The amount of organic carbon stored is the difference
between all OC inputs and losses from the soil due to
different factors as below
However, without continual inputs of OC, stored OC
decreases gradually due to microbial decomposition
Soil OC Inputs Soil OC Losses
Cinput = Coutput………………Steady state condition
Cinput < Coutput……………....Depletion
Cinput > Coutput……………....Sequestration
Plant materials (crop residues,
plant roots, root exudates)
and animal manure
decomposition by microorganisms,
erosion of surface soil and off take
in plant and animal
18

19. SOC pool
1550 Gt
Erosion
Redistribution
over the
landscape
C added in
above ground
residues, and
roots biomas
Aquatic
systems
Deposition
in aquatic
ecosystems
and burial in
depressional sites
CO2 CO2
CO2
CO2
CO2
Humification
2-20% of
the C
added
Particle
detachment
Trans-
location
Leaching of
DOC
*DOC= dissolved organic carbon
0.8 - 1.2 Gt
0.4 - 0.6 Gt
Fig. 9: Processes affecting SOC dynamics
Source: Lal (2004)19

20. POTENTIAL OC
ATTAINABLE OC
ACTUAL OC
Climate
(Rainfall,
temperature,
solar rediation)
Plant productivity,
rotation strategy,
residue management
soil management
Major factors that determines storage of carbon in soil
Soil type
(Clay Content,
Depth,
Bulk density,
mineralogy)
Defining
factor
Limiting
factor
Reducing
factors
Optimize water and
nutrient use efficiency
Add external
sources of carbon
SOC actual SOC attainable SOC potential
Organic carbon storage in soil
Soilcarbonsequestration
Ingram and Fernandes (2001)

21. Soil carbon density
(kg m-2) designated by
different colour in the
map (1 m depth)
Status of soil organic carbon stock in India
Soil Organic Carbon
stock in Indian soil
22.72±0.93 Gt
Sreenivas et al.( 2016)21

22. Status of soil inorganic carbon stock in India
Soil Inorganic Carbon
stock
12.83±1.35 Gt
Soil carbon density
(kg m-2) designated by
different colour in the
map (1 m depth)
Total Carbon stock
of Indian Soils
=35.55 ±1.87Gt
Sreenivas et al. (2016)22

23. Table: Soil carbon stock in different bio-climatic system in India
23
Bio-climatic
System
Coverage
(Mha)
SOC Stock
(Pg)
SIC Stock
(Pg)
Total
Carbon
Stock (Pg)
Arid cold 15.2 0.6 0.7 1.3
Arid hot 36.8 0.4 1.0 1.4
Semi-arid 116.4 2.9 1.9 4.8
Sub-humid 105 2.5 0.3 2.8
Humid to
per humid
34.9 2.1 0.04 2.14
Coastal 20.4 1.3 0.07 1.37
Range in rainfall;
arid= <550 mm; semi-arid= 550-1000mm;
sub-humid= 1000-1500 mm; humid to per humid= 1200-3200 mm
Bhattacharya et al. (2008)

24. Region
SOC content
Percent
reduction
Cultivated
(g kg-1 )
Native
(g kg-1 )
1. Northwest India
Indo-Gangetic plains
Northwest Himalaya
4.2± 0.9
24.3 ± 8.7
10.4± 3.6
34.5 ± 11.6
59.6
29.6
2. Northeast India 23.2 ± 10.4 38.3± 23.3 39.4
3. Southeast India 29.6± 30.1 43.7 ± 23.4 32.3
4. West coast 13.2 ± 8.1 18.6 ± 2.1 29.1
5. Deccan plateau 7.7 ± 4.1 17.9 ± 7.6 57.0
Depletion of SOC concentration of cultivated compared
with that in Undisturbed soils
Source:Swarup et al. (2000)
24

25. Causes of depletion of organic carbon pool in soils of
India
Faulty Soil and crop management practices
Jhum (shifting) cultivation
SOC pool in traditional jhum cultivation (30 cm depth) was
21 t ha-1, whereas SOC pool under best management
practices (6 years ) was 30-40 t ha-1 (Lenka et al., 2012)
Deforestation
Conversion of natural to agricultural ecosystems
Climatic factors- Temperature, Precipitation
25

26. Distribution of organic and inorganic Carbon in relation to
rainfall and temperature in India
• Srinivasarao et al., 2009a).
Srinivasarao et al. (2009)
Fig.10.a:(A) Soil carbon stocks in rainfed production systems in relation to
rainfall and
(B)relationship between mean annual rainfall (mm) and soil
organic carbon in surface layer (0–15 cm) under rainfed conditions
26

27. Fig. 10. b: Relationship between
(A) mean annual C inputs and mean C depletion rate (top left),
(B) mean annual rainfall and mean C depletion rate (top right), and
(C) critical C input requirement and mean temperature in seven long-term
experiments in diverse rainfed regions of India.
(Cont.)
27

28. Impact of soil organic carbon depletion
The loss of soil fertility and agricultural production
Negative nutrient /elemental balance, negative water balance
Reduction in soil biodiversity
Further accentuates the depletion of SOC
Increased greenhouse gas emissions and accelerated climate
change
‘Soils means nothing without carbon for crop production’
 Most soils in agricultural ecosystems have lost soil C ranging from 30 to
60 t C ha-1 with the magnitude of 50 to 75% loss (Lal, 2004)
28

29. SOC SEQUESTRATION
Soil organic carbon sequestration is the process by which carbon is
fixed from the atmosphere via plants or organic residues and stored
in the soil. When dealing with CO2, SOC sequestration involves
three stages:
1) the removal of CO2 from the atmosphere via plant photosynthesis;
2) the transfer of carbon from CO2 to plant biomass; and
3) the transfer of carbon from plant biomass to the soil where it is store.
 Mechanism of stabilization of newly
added SOC (Kane, 2015)
 Physically, inside soil micro- and macro
aggregates where it is inaccessible to
soil organisms.
 Chemically, strongly adsorbed to clays
via chemical bonds which prevents the
consumption of carbon by organisms.
 Biochemically, re-synthesized into
complex molecule structures that may
hinder decomposition. 29

30. Carbon Sequestration potential in soils of India
Process
Carbon
sequestration
potential
(Tg C/ y)
A. Soil organic carbon (SOC)
-Restoration of degraded soils 7.2-9.8
-Agricultural intensification on un-degraded soils 5.5-6.7
B. Sequestration of secondary carbonates 21.8-25.6
C. Erosion control 4.8-7.2
Total 39.3-49.3
Source: Lal ( 2015)
30

31. Degradation process
Area
(M ha-1)
SOC sequestration
rate
(kg C ha-1 yr-1 )
Total SOC
sequestration
potential
(Tg C yr-1)
Water erosion 32.8 80-120 2.63-3.94
Wind erosion 10.8 40-60 0.43-0.65
Soil fertility decline 29.4 120-150 3.53-4.41
Water logging 3.1 40-60 0.12-0.19
Salinization 4.1 120-150 0.49-0.62
lowering of watertable 0.2 40-60 0.01-0.012
Total 7.2-9.82
Soil organic carbon sequestration through restoration
of degraded soils
The global technical potential of terrestrial C sequestration is some 333 Pg C (367.1 ×
109 tn C) by the end of the twenty-first century, equivalent to atmospheric CO2
drawdown of 156 ppm..
Source: Lal (2015)31

32. Strategies of SOC sequestration
Restoration of soil degraded by
Adoption of RMPs on agricultural
and forest soils
Erosion
Salinization and
alkalinization
Pollution and
contamination
Nutrient depletion
Acidification and
leaching
Crusting and
structural decline
Precision farming and
fertilization
Diverse crop rotations,
agroforestry
Integrated pest
management (IPM)
No-till farming with
residue mulch and
cover crops
Integrated nutrient
management (INM)
Restoringphysical,chemical&
biologicalqualityofdegradedsoils
Agriculturalintensificationtoincrease
productivity
Converting surplus agricultural land for nature
conservancy & environmental improvements 32

33. 1. Converting degraded lands to perennial vegetation
Principal options to achieve these
(Cont.)
• The rate of soil C sequestration is 300–350 kg/ha/yr through
conversion to a perennial land use (Post and Kwon 2000).
33

34. 2. Increasing net primary productivity (NPP) of agricultural
ecosystems
Where,
GPP = Gross Primary Productivity
(for a given length of time, the total rate of carbon captured and stored by
ecosystem as plant biomass )
RES = Plant Respiration,
NPP = Net Primary Productivity (the amount of carbon uptake after subtracting RES).
NPP = GPP – RES
3. Converting plow tillage to no-till farming
 Increases SOC pool, especially in the surface layer.
 More effective in C sequestration in lighter textured soils
Conversion from plow
tillage to no-till
400–600 kg ha-1 yr-1 West and Post (2002)
Intensification of
agricultural ecosystems
100–200 kg ha-1 yr-1 Lal et al. (1998)
Table 1: The global mean rate of SOC sequestration
34

35. Technological options to create a positive soil C budget
35

36. Research reviews on
1. Relation of SOC with soil properties
 Physical
 Chemical
 Biological
2. Management of carbon stock in soil through
Conservation Agriculture
 Crop management
 Conservation tillage
 Residue management
Integrated nutrient management
Organic amendments
Agroforestry 36

37. Fig: Dark colored topsoil showing
high levels of SOC due to
abundant plant roots and their
associated soil fauna and
microbes in a cultivated soil..
Fig: Soil in a long-term experiment
appears red when depleted of
carbon (left) and dark brown
when carbon content is high
(right)
Lal (2003)

38. Fig.Relationship between soil organic carbon and water stable macro-
aggregates under Influence of rice straw and farm yard manure (FYM)
application. ( Data pooled for treatments and the three soil depths.)
Benbi and Senapati (2009)PAU, punjab 38

39. Fig. 5. Correlation of SOC concentration with physico-chemical properties
Brar and Singh (2014)Ludhiana

40. Fig. Inter-correlation between bacterial abundance and particulate organic
carbon as well as soil microbial activity
Gowda et al. (2017)Karnataka
40

41. Management of Carbon Stock in Soil
41

42. Crop management
42

43. Cropping systems Organic C
(%)
Soil organic carbon
stock (t ha-1)
Rice-wheat-fallow 0.58 12.992
Rice-wheat-fodder (maize + cowpea) 0.61 13.664
Rice-wheat-green gram 0.68 15.232
Rice- mustard-fallow 0.56 12.544
Rice-mustard-fodder(maize + cowpea) 0.60 13.44
Rice-mustard-green gram 0.65 14.56
Uncultivated soil 0.51 11.424
Initial SOC status 0.52 11.648
LSD (P=0.05) 0.05 1.12
Sharma and Bali (2000)Jammu, Jammu and Kashmir
Table 5: Soil organic carbon status under different cropping
systems (after 6 years) at 0-15 cm depth
43

44. Table: Soil carbon sequestration rate by different cropping system
in Vertisol of India (0-30 cm depth)
Location
(State)
Cropping
system
Cropping
period
Initial
SOC Mg
ha-1
SOC
Mg ha-1
C-
sequestration
kg ha-1 y-1
Madhya
pradesh
Paddy-Wheat 1982-2002 19.8 22.5 135
Maharashtra Citrus 1982-2002 22.0 36.9 745
Maharashtra
Cotton/
Greengram +
Pigeon pea
1982-2002
17.3 35.0 885
Gujarat
Groundnut-
wheat
1978-2002 27.3 31.9 209
Karnataka Paddy- paddy 1974-2002 18.61 43.6 861
44
Manna and Subha Rao
(2012)

45. Table 7: Effect of long term (after seven years) diversified crop
rotation on soil organic carbon pool in different soil layers.
Treatment SOC stock (t ha-1)
0-15 cm 15-30 cm 30-45 cm
Initial value 4.40 4.21 3.70
Cropping systems
Maize-Wheat-Mungbean 6.33a 5.53a 4.32a
Maize-Chickpea-Sesbania 6.56a 5.66a 4.41a
Maize-Mustard-
Mungbean
5.45b 4.56c 4.07a
Maize-Maize-Sesbania 5.51b 5.13b 4.12a
Parihar et al. (2016)IARI, New Delhi
Same letters within each column indicate no significant difference among the
treatments (at P < 0.05) following LSD test
Soil type: Sandy loam
45

46. T1 - Sunnhemp - Rice - Blackgram ,
T2 - Sunnhemp - Rice – Sesame,
T3 - Sunnhemp - Rice + Daincha - Maize + Green gram
T4 - Sunnhemp - Rice + Daincha - Bhendi ,
T5 - Sunnhemp - Rice + Daincha – Ragi,
T6 - Sunnhemp - Rice + Daincha – Varagu,
T7 - Sunnhemp - Rice + Daincha - Fodder Cowpea
Fig 2: Influences of different cropping sequences on Carbon sequestration
Yazhini et al. (2019)TNAU, Coimbatore

47. Minimum soil disturbance
Conservation tillage & crop residue management
Conventional agricultural practices such as ploughing, removal of crop residues
accelerated soil erosion which are mainly responsible for low SOC in cultivated soils.
Soil erosion alone leads to a soil C loss of 4.3 to 7.3 Tg C/ y. (Lal, 2004) 47

48. Treatments
Total SOC stock
(Mg C ha-1)
0-5 cm 5-15 cm
CT-CT (year-round conventional Tillage) 7.93b 14.66a
CT-NT (CT in the Rabi season and NT in the Kharif) 8.82ab 15.05a
NT-CT (NT in the Rabi season and CT in the Kharif) 9.03a 14.99a
NT-NT (year-round no tillage) 9.43a 15.38a
Table 1. Impacts of tillage practices on total soil organic carbon (SOC)
stock after 6 yr of rainfed cropping at the 0- to 15-cm soil layer in
the Indian Himalayas
Bhattacharyya et al. (2013)IARI, New Delhi
48

49. Treatment
SOC
(%)
Total SOC stock
(0-30 cm depth)
(t ha-1)0-5 cm 5-15 cm 15-30 cm
Tillage
Conventional tillage 0.98 0.76 0.57 28.2
Zero tillage 1.19 0.89 0.55 30.8
LSD (P=0.05) 0.16 0.11 NS 1.8
Nutrient management
NPK 0.97 0.69 0.54 26.7
NPK + FYM (5 t ha-1) 1.11 0.87 0.55 29.9
NPK + Wheat residues(5 t ha-1) 1.13 0.80 0.57 29.7
FYM (5 t ha-1) 1.10 0.89 0.56 30.3
Wheat residues(5 t ha-1) 1.12 0.89 0.58 31.0
LSD (P=0.05) 0.12 0.14 NS 1.6
Table 9: Effect of tillage systems and nutrient management options
on SOC content and SOC stock in top 30 cm soil
Hati et al. (2015)IISS, Bhopal Soil type : Clay
49

50. Table 10: Effect of long term (after seven years) tillage practices
on soil organic carbon pool in different soil layers.
Treatment SOC stock (t ha-1)
0-15 cm 15-30 cm 30-45 cm
Initial value 4.40 4.21 3.70
Tillage
Permanent raised bed 6.54a 5.53a 4.27a
Zero tillage 6.51a 5.66a 4.34a
Conventional tillage 4.83b 4.47b 4.09a
Parihar et al.(2016)IARI, New Delhi
Within column, value represents with different letter indicates significant
difference (P = 0.05).
Soil type: Sandy loam
50

51. Tillage treatment
Mean
SOC
(%)
SOC stock (t ha-1)
0-15 cm 15-30
cm
30-45
cm
Conventional tillage 0.26c 6.20c 6.16d 6.28c
Reduced tillage 0.34b 7.85b 7.91c 7.85b
Zero tillage 0.39a 8.89a 8.78a 8.72a
Furrow irrigated
raised bed
0.36b 8.21b 8.21b 8.26a
Table 11: Effect of various tillage methods in mustard based cropping
systems on soil organic carbon content and SOC stock after 4
years (2009-2012)
Initial soil organic carbon: 0.26 %; Within column, value represents with different letter
indicate significant difference (P = 0.05).
Shekhawat et al.(2016)Bharatpur, Rajasthan Soil type: Clay loam 51

52. Treatments
Total SOC pool
(Mg ha-1)
0-30 cm
C-
sequestration
potential
(0-30 cm)
(Mg ha-1)
Conventional tillage 28.84c -
Permanent narrow bed 31.38b 2.54c
Permanent narrow bed with residue 33.80ab 4.96ab
Permanent broad bed 33.51ab 4.67ab
Permanent broad bed with residue 34.43a 5.59a
Zero tillage with residue 34.23a 5.39a
zero tillage 33.19ab 4.35b
Table: Impacts of conservation agriculture on total soil organic pool
and C-sequestration potential in a maize-wheat system (after 3 yrs)
Das et al. (2018)IARI, New Delhi 52

53. Integrated Nutrient Management
53

54. Table: SOC and carbon sequestration under different fertilization
in long- term mono cropping of groundnut
Treatments
0-20 cm soil depth
SOC
(Mg ha-1 )
Carbon
sequestration
(Mg C ha-1 )
Carbon
sequestration
rate
(Mg C ha-1 yr-1 )
Control 32.2 d -3.57 d -0.18 d
100% NPK 36.2 c 0.43 c 0.02 c
50% NPK+ 4 Mg ha-1 GNS
(Groundnut Shell)
47.2 a 11.43 a 0.57 a
50% NPK+ 4 Mg ha-1 FYM 45.9 a 10.13 a 0.51 a
5 Mg ha-1 FYM 42.4 b 6.63 b 0.33 b
Hyderabad, Sandy loam, pH= 6.1 Srinivasarao et al. (2012)
100% NPK=N: P2O5: K2O- 20: 40:40kg ha-1)
54

55. Figure :Profile SOC and mean C sequestration rate as affected by 22 years
of sorghum cropping with differential manuring and fertilization
Srinivasarao et al. (2012)AICRPDA, Solapur, Maharashtra
Leu- Leucaena (23.2 g kg-1 N, C:N : 59.1:1
CR- Sorghum Crop residue (4.9 g kg-1 N ,C:N : 89:1)
FYM (5.6 g kg-1 N, C:N : 11.2:1)

56. Treatments
Walkley Black
C
(g kg-1)
KMnO4- -
oxidizable labile
C (mg kg-1)
Microbial
biomass C
(mg kg-1)
After
maize
After
wheat
After
maize
After
wheat
After
maize
After
wheat
T1 : Control 3.09 3.10 510 519 220 216
T2 : 100% NPK 3.15 3.38 531 537 248 237
T3 : Vermicompost @ 5mg ha-1
3.50 3.75 555 859 250 242
T4 : NADEP compost @ 5mg ha-1
3.35 3.56 534 779 255 238
T5 : FYM @ 5mg ha-1
3.37 3.70 556 815 264 238
T6 : 50 % NPK + Vermicompost @ 5mg ha-1
4.03 4.10 628 931 281 259
T7 : 50 % NPK + NADEP compost @ 5mg ha-1
3.96 4.03 573 832 260 246
T8 : 50 % NPK + FYM @ 5mg ha-1
3.91 4.05 592 877 274 244
CD (p= 0.05) 0.09 0.10 60 51 14.7 10.2
Initial 3.30 520 248
Table: Changes in carbon pools in soil after maize and wheat as affected by
value-added manures and chemical fertilizers in a maize-wheat
cropping system
IARI, New Delhi Basak et al. (2012)Sandy loam, pH-7.6
Recommended Dose of N: P2O5: K2O- 120: 60: 60 kg ha-1)
56

57. Treatments
0-15 cm soil depth
SOC
(g kg-1 )
Carbon
sequestration
(Mg C ha-1 )
Carbon
sequestration
rate
(Mg C ha-1 yr-1 )
Control 3.26 d 1.94 c 0.22 c
100 % N 3.53c 2.18 c 0.24 c
100% NP 3.69 c 2.16 c 0.24 c
100% NPK 4.11 b 3.30 b 0.37 b
100 % NPK+ FYM 4.55 a 4.10 a 0.46 a
Ludhiana Brar et al. (2013)
Table: Effect of manure and inorganic fertilizers on carbon
sequestration under rice- wheat cropping system
Loamy sand, pH=8.3
100% NPK (120:60:40 kg N: P2O5: K2O ha-1 )
57

58. 58
Treatment Soil organic
carbon
(g kg-1)
Total soil
organic
carbon
stock (t ha-1)
SOC
sequestration
rate
(t ha-1 year-1)
T1- Dhaincha@ 25 kg seed/ha 7.84 34.16 1.98
T2- T1+ FYM 5t/ha (basal) 9.32 41.34 3.17
T3- T1+ Vermicompost 2t/ha (basal) 11.25 44.30 3.67
T4- T1+ Vermicompost 2t/ha (split) 11.43 45.81 3.92
T5- T1+ FYM 5t/ha + Vermicompost
2t/ha (split)
11.50 46.29 4.00
T6- T1+ FYM 5t/ha + Vermicompost
2t/ha (basal)
10.52 43.32 3.50
T7- T1+ FYM 5t/ha + Panchgavya 10.24 42.62 3.35
CD (P=0.05) 1.58 3.86 0.81
Pradhan et al.(2015)Bhubaneswar (Odissa)
Initial status of SOC- 5.2 g/kg, pH- 6.0
Table 17: Effect of organic nutrient management on soil organic carbon
stock and carbon sequestration rate under rice-rice cropping
sequence

59. Treatments
Total SOC content
(Mg ha-1)
0-90 cm soil layer
SOC
accumulation
Rate
(kg C ha-1 yr-1)
Recalcitrant
SOC content
(Mg ha-1)
SOC
sequestration
rate
( kg C ha-1yr-1)
Control 31.00d - 21.89c -
N 36.30d 120.48e 23.74bc 42.1d
PK 42.15c 254.46d 25.32b 78.1c
100 % NPK 54.27b 528.90c 29.17a 165.6c
150% NPK 60.77a 676.70b 30.55a 196.9b
NPK+ FYM 63.80a 745.45a 31.73a 223.7a
Table: Total SOC accumulation and sequestration rate as affected by
44 years long-term fertilization under wheat based cropping
system
Treatment details:
100% NPK (120:60:40 kg N: P2O5: K2O ha-1)
150% NPK: (180:90:60 kg N: P2O5: K2O ha-1)
NP: (100% NP)
N (100% N)
NPK+ FYM: ( 100% NPK & FYM @ 5 Mg ha-1)
IARI, New Delhi Ghosh et al. (2018)59

60. Organic amendments
60

61. Table12:Long term (2007-2013) effect of different nutrient
amendments on soil organic carbon (0-20 cm)
Anand et al. (2015)Bhavnagar, Gujarat
Organic amendment SOC %
SOC stock
(t ha
-1
)
Jatropha press cake @4 t ha
-1
2.32b 55.68 b
Farmyard manure @ 20 t ha
-1
3.04a 72.96a
Initial value 0.71 17.04
*Within column, value represents with different letter indicate significant
difference (P = 0.05)
* An experiment was designed on degraded wastelands
Soil type: loamy

62. Table: Effect of different biochar on total soil carbon at the end of one
year of carbon mineralization
Purakayastha et al . (2015)New Delhi

63. Agro-forestry
Agroforestry system recognized as a carbon sequestration strategy
because of its applicability in agricultural lands as well as in
reforestation program which offers the highest potential for carbon
sequestration .
Direct role: Carbon sequestration rate ranging from 0.3 to 15.2 Mg
C /ha/yr ( Nair et al. 2011)
Indirect role: It helps to reduce pressure on natural forests
Wheat in Agro-forestryPotato in Agro-forestry
63

64. Table: Total soil organic pool (Mg ha-1) affected by poplar
(Poplulus deltoides) based agro-forestry
Ludhiana Gupta et al. (2009)
Land use
0-15 cm soil layer
Tree age (years)
One Three Six
Agroforestry 12.4 14.6 15.8
Sole crop
(wheat)
9.0 9.6 9.2
LSD (0.05) 1.6 1.1 0.9
15-30 cm soil layer
Agroforestry 10.8 11.3 13.3
Sole crop
(wheat)
8.10 8.32 8.10
LSD (0.05) 1.1 0.9 0.7
Sandy loam, pH= 7.9
64

65. Table 1. Biomass (Mg ha-1) and carbon stock (Mg ha-1) in selected
land-use systems in Kachchh
Tree species
Above
ground
biomass
Below
ground
biomass
Total
biomass
Carbon
stock
(above
ground)
Carbon
stock
(below
ground)
Total
plant
carbon
stock
Acacia 12.78 2.52 15.30 5.03 0.98 6.02
Neem 7.79 1.85 9.64 2.92 0.71 3.64
CC 6.26 4.70 10.96 2.44 1.82 4.26
CS 2.78 1.75 4.53 1.04 0.71 1.74
Acacia+ CC 12.93 4.49 17.41 5.08 1.75 6.82
Acacia+ CS 12.55 3.14 15.69 4.91 1.24 6.15
Neem+ CC 9.60 3.79 13.39 3.53 1.39 4.91
Neem+ CS 9.35 3.12 12.48 3.65 1.22 4.87
LSD 5% 2.30 0.82 2.99 0.92 0.33 1.18
Mangalassery et al. (2014)
CC-Cenchrus ciliaris , CS- Cenchrus setegerus)
Bhuj, Gujarat

66. Table 15.Organic carbon in soil after six years of plantation with
different land use options
System
Organic carbon
(%)
0-15 cm 15-30 cm
Sole cropping 4.2 3.7
Agro-forestry 7.1 7.3
Agro-horticulture 7.3 7.4
Agro-silviculture 3.8 5.6
Manna et al. (2015)IISS, Bhopal
66

67. 67
Table: Tree biomass, soil organic carbon and total carbon density
under different MPTs after 30 years of plantation in
North Gujarat
Treatments Soil organic
carbon
(%)
Carbon
sequestration
Mg ha-1
Carbon
sequestration
rate
Mg ha-1yr-1
Neem
(Azadirachta indica)
39.85 447 50
Khejdi
(Prosopis cineraria)
30.13 484 55
Gando baval
(Prosopis juliflera)
27.84 765 68
Israel babool
(Acacia tortolis)
39.09 594 67
Patel and Shakhela (2016)S. K. Nagar, Gujarat Sandy loam

68. Agro forestry System Total CO2
sequestration
(Mg ha-1 )
CO2 sequestration
(Mg ha-1 yr-1)
Ardusa+ Greengram
(Age 7 yrs)
160.70 22.95
Simarouba + Mustrad
(Age 5 yrs)
85.27 17.05
Custard apple + Fodder
(Age 4 yrs)
8.80 1.76
Average of four tree species
(Age 30 yrs)
(Block plantation)
1811.00 60.36
Average of thirteen MPTs
(Age 20 yrs)
(Boundary Plantation)
9.03- 758.44 0.45- 37.92
Table: CO2 sequestration in different agroforestry system in arid
and semi- arid conditions of North Gujarat
S. K. Nagar, Gujarat Anonymous, (2017)

69. CONCLUSION
• Restoration of SOC to threshold levels of at least 11 to 15 g kg-1 (1.1%–
1.5% by weight) within the root zone is critical to reducing soil and
environmental degradation risks.
• Adoption of RMPs for management of SOC is critical to enhance and
maintain soil health.
• Conservation agriculture practices (reduced tillage , crop cover, crop
residue managents) with minimum soil disturbance promote buildup of
SOC.
• Soils under diverse cropping system and incorporation of legumes in crop
rotation (greengram, cow-pea etc) or as green manure ( sunnhemp, dhaincha
etc) have significant role in improvement in SOC stock.
• Combined use of NPK+ FYM showed increase in SOC content compared to
NPK or FYM alone which was about 25-38 per cent more C than in control.
• Conversion of organic residues to biochar could be a viable technology for
long-term deposition of C and climate change mitigation strategy.
• Agroforestry system like agri-slivi-culture, slivipasture, agri- horticulture
offer both adaptation and mitigation opportunities for climate change besides
contribution to SOC. 69

70. POLICY INTERVENTIONS
Incentivization is needed to motivate small land holders toward
adoption of RMPs.
Relevant policy interventions are needed to achieve the following:
 Improving soil quality through enhancing C sequestration for food
security and climate change adaptation and mitigation..
 Implementing suitable policy supports (e.g., nutrient-based subsidy
or NBS) for ensuring balanced use of fertilizers,
 Subsidy on use of organic manures,
 Adequate extension support for increasing awareness among the
farmers about the need for soil quality management and C
sequestration, campaign against residue burning, and
 Encouraging the farmers to retain the CRs that do not have any
alternate uses, better mechanization for spreading the residues, etc.
70

71. Sustainable
Soil
Management
Soil Health
Card
Neem Coated
Urea
Agroforestry
Policy
Climate
Programe
NMSA
Organic
Farming
Contingency
Plans
NICRA
Government policies and programmes contributes to soil
carbon sequestration in India
71

72. GLOBAL SOIL ORGANIC CARBON MAP
(GSOCmap)
The GSOCmap
provides users with
very useful
information to
monitor the soil
condition, identify
degraded areas, set
restoration targets,
explore SOC
sequestration
potentials, support the
GHGs emission
reporting under the
UNFCCC and make
evidence based
decisions to mitigate
and adapt to a
changing climate.
The GSOCmap represents the first ever global soil organic carbon assessment
produced through a participatory approach in which countries developed their
capacities and stepped up efforts to compile all the available soil information at
national level.
72

73. FUTURE RESEARCH NEEDS
• Establishing new and continuation of the existing long-term (>10
years)field experiments to quantify the influence of RMPs on the
soil C sequestration in diverse ecosystems and crop production
systems, GHG emissions, and ecosystem services.
• Quantifying soil C sequestration potential for diverse land use and
management scenarios at regional and national levels.
• Providing research information on soil C sequestration and the
corresponding rates under “on-farm” conditions for recommended
land use and management practices.
• Developing the cost-effective, credible, transparent, and simple
methods of measuring the rate of soil C sequestration.
• Efforts are needed to create large-scale awareness against burning
of crop residues.
73