2. Rice cultures and Greenhouse Gas
(GHGs) emission: Way forward
JAGADISH
PHD15AGR5009
1ST Ph.D
Dept. of Agronomy
3. SEQUENCE Of PRESENTATION
Introduction
Rice cultures and contribute to GHGs
Greenhouse gasses(GHGs)
Mitigation of GHGs
1. Transplanted rice
2. System of rice intensification
3. Direct seeded rice
4. Aerobic rice
Conclusion
7. Impact of climate change and GHGs in Agriculture
1. Reduction in crop yield
2. Shortage of water
3. Irregularities in onset of monsoon, drought, flood
and cyclone
4. Rise in sea level
5. Decline in soil fertility
6. Loss of biodiversity
7. Problems of pests, weeds and dieses
8.  An increase of 2 - 4oC results to 15% reduction in yields
 Rainfed and drought prone areas-17 to 40%
 Water scarcity affects 23 mha in Asia
 Additional CO2 can benefit crops, this effect was nullified
by an increase of temperature
 May decrease in rice production by 25-30 % yield
Impact of climate change on Rice production
Note: Food Security of India started shaking because of rice is
the lion share in food grain production
10. Transplanting is the most common method of crop establishment
for rice in Asia.
Rice seedlings grown in a nursery are pulled and transplanted into
puddled and levelled fields 15 to 40 days after seeding (DAS).
Rice seedlings can either be transplanted manually or by machine.
Limitations:
1. Transplanting is tedious and time-consuming
2. Loss water resources
3. Labour requirement is more
1 kg rice = 5000 litre of water
Transplanted RICE
11. DIRECT SEEDED RICE
 Around 30% of the total water saved for rice cultivation as compared to puddling
and transplanting
METHODS OF DIRECT SEEDING:
1. Wet DSR :-
 Sprouted seeds on wet puddle soil
 Srilanka, Vietnam, Malaysia, Thailand, India
2. Dry DSR:
 Dry seeding – Broadcasting or drilling
 USA, Punjab, Haryana
 30% labour saving, 15-30 % cost saving & 10 - 15 days early harvest
3. Water seeding:
 Pre germinated seeds –
 broadcasting with machines or aero planes.
 USA, Australia.
12. 8-10 Days (2 leaf stage) nursery Careful uprooting & transplanting Square planting (25X25cm)
Weeding with cono weeder Saturation of the field High organic compost
System of Rice Intensification
13. Aerobic rice
 Aerobic rice is a production systems in which rice is grown in well-drained,
non-puddled and non-saturated soils with appropriate management.
 Cultivation fields will not have standing water but maintained at filed
capacity
 Weed infestation and competition is more severe in aerobic rice compared to
transplanted rice.
Advantage
• Saving of water
• Puddling and submergence is not requiring
• Nursery and transplanting is not required
• Less seed rate
Important varieties
• Mas-946-1
• MAS-25, 26
• Jaya
15. GHGs and Non-GHGs
The major atmospheric
constituents
1. Nitrogen (N2)
2. Oxygen (O2)
3. Argon (Ar)
4. Other remaining gases
Note: Molecules
containing two atoms of
the same element
Gases that trap in the
atmosphere are called
GHGs
1. Water vapour
2. CO2
3. Methane
4. Nitrous oxide
5. Fluorinated gases
19. • Carbon dioxide (CO2) is
colourless and odourless.
• The density of carbon dioxide is
around 1.98 kg/m3, about 1.67
times that of air.
• At present (2015): nearly 400 ppm
in the atmosphere
• Lion share in the GHGs
• Source: Organic matter
decomposition, Industries,
Transport, Burning etc.
20. Methane (CH4)
• Methane (CH4) is the 2nd most prevalent
GHGs (Nearly 18%) from human
activities.
• CH4 is more efficient at trapping radiation
than CO2.
• Evolved from methonogenesis process
• Anaerobic condition type
• Agricultural activities, waste management,
energy use, and biomass burning all
contribute to CH4 emissions.
• Agriculture: Rice cultivation
21. Nitrous oxide (N2O)
3rd most significant greenhouse gas
and it contribute to nearly 6 % to
GHGs
Denitrification process is involved
It produces in aerobic soil condition
Agricultural activities like fertilizer
are the primary source of N2O
emissions.
Biomass burning also generates
N2O
23. Fig. 04: Relationship between CH4 and N2O emission and redox potential in
rice field throughout the season
24. Fluorinated gases
• Fluorinated gases (F-gases) are
man-made gases that can stay in the
atmosphere for centuries and
contribute to a global greenhouse
effect.
There are four types:
1.Hydrofluorocarbons (HFCs),
2. perfluorocarbons (PFCs),
3. Sulfur hexafluoride (SF6) and
4. Nitrogen trifluoride (NF3).
26. Table 2: Emission of methane and nitrous oxide (Gg yr-1)
from agricultural soils of different major states of India
State Methane N2O GWP (CO2)
Andra Pradesh 398.96 21.29 16319.76
Bihar 334.77 10.76 11575.59
Chhattisgarh 261.3 4.83 7973.80
Gujarat 64.67 13.45 5625.88
Karnataka 66.49 18.97 7315.27
Source: IPCC report (2014)
27. Fig. 5: Comparison of Methane and Nitrous oxide emission in Indian scenario
West Bengal Bhatia et al. (2014
28. 1. Ebullition,
2. Diffusion, and
3. Transport through rice plants.
Ebullition
Dominates during initial period
and upon disturbance of soil due to
weeding, harrowing etc.
Diffusion
due to partial pressure difference
Transport through rice plants
Averaged about 95 and 89% at tillering and PI stages.
CH4 escapes from the rice fields to the atmosphere through
29. a) as a source of substrate for methanogenic bacteria,
b) as a conduit for CH4 through aerenchym, and
c) as an active CH4 oxidizing-site in rhizosphere by
transporting O2
Why methane emission is more in Rice..?
The path of CH4 through the rice plant includes
a)Diffusion into the root,
b) Conversion to gaseous CH4 in the root cortex,
c) Diffusion through cortex and aerenchyma, and
d) Release to the atmosphere through microspores in
the leaf sheaths.
30. Fig. 5: Schematic diagram of methane production, oxidation and emission
from paddy field
32. Global Warming Potential: The global warming potential is an
index developed to compare the strengths of different GHGs in
temperature on a common basis.
CO2 equivalent: is used as the reference gas to compare the ability of
a GHG to trap atmospheric heat relative to CO2 . Thus, GHG
emissions are commonly reported as CO2 equivalents (e.g. in tonnes of
CO2 eq.).
The GWP is a time integrated factor, thus the GWP for a particular gas
depends upon the time period selected.
The GWP of agricultural soils may be calculated using equation
GWP = CO2 + CH4 x 21 + N2O x 296 (IPCC, 2007)
Terms and formula
33. Instruments needed for collection of gases
Gas chamber Dispo van and Needle
lock needle Gas Chromatography
37. Fig.6: a) CO2 quantity evolved in different treatments and
b) CO2 quantity evolved from rice growth stage
Treatment detail
C: Control plots without
fertilizer
A: Organic fertilizer
(cow manure)
B: Organic fertilizer
pellets
R: Chemical fertilizer
Source: Pantwat (2012)
Thailand
38. Fig.7: a) CH4 quantity evolved in different treatments and
b) CH4 quantity evolved from rice growth stage
Treatment detail
C: Control plots without
fertilizer
A: Organic fertilizer
(cow manure)
B: Organic fertilizer
pellets
R: Chemical fertilizer
Source: Pantwat (2012)
Thailand
39. Fig.8: a) N2O quantity evolved in different treatments and
b) N2O quantity evolved from rice growth stage
Treatment detail
C: Control plots without
fertilizer
A: Organic fertilizer
(cow manure)
B: Organic fertilizer
pellets
R: Chemical fertilizer
Source: Pantwat (2012)
Thailand
40. Table 4: Comparison of CH4 emission under different
water and nutrient application
Nitrogen fertiliser
applied
Range of CH4
fluxes (gm-2 d-1)
CH4
emission
factor
(gm-2 d-1)
Comparison
(%)
Min Max
Urea -0.030 0.41 0.22 100
Ammonium sulphate -0.010 0.28 0.18 81.6
Slow released fertilizer -0.001 0.42 0.19 86.1
Korea Soon kuk et al. (2014)
41. Table 5: Emission coefficient and total methane
emission in various rice-ecosystems
42. Table 6: Comparison of CH4 emission under different water
and nutrient application
Water
management
Range of CH4 fluxes
(gm-2 d-1) CH4 emission
factor (gm-2 d-1) Comparison (%)Min Max
Continuous
flooding
-0.0008 0.43 0.13 100
Intermittent irrigation -0.004 0.30 0.09 69.2
Korea Soon kuk et al. (2014)
43. China Zucong et al. (2010)
Note: 100S- 100 kg N ha-1 Ammonium sulphate (S)
300S- 300 kg N ha-1 Ammonium sulphate (S)
100U- 100 kg N ha-1 Urea (U)
300U- 300 kg N ha-1 Urea (U)
Table 7: Methane emission from flooded rice as influenced by
different N source
44. Note: Solid bar show state wide averages
Error bar show one standard deviation
Punjab Pathak et al. (2012)
Fig.9: Mid season drainage reduces GHG emission from transplanted paddy
TonsofCO2eperhectare
45. Methane efflux (mg plant-1 day-1)
Treatments 30 DAT 60 DAT 90 DAT 120 DAT Mean
Neem coated urea
(NCU) + DAP
0.27 2.67 4.10 3.77 2.70
Neem coated urea
(NCU) + SSP
0.17 2.36 3.81 3.32 2.41
Ammonium
sulphate (AS) +
DAP
0.40 2.94 5.23 4.58 3.28
Ammonium
sulphate (AS) +
SSP
0.34 2.97 4.57 4.32 3.05
Urea + DAP 1.0 5.36 6.29 5.83 4.62
Urea + SSP 0.93 5.19 6.05 5.57 4.43
Table 8: Methane efflux of rice at different growth stages as influenced
by slow releasing nitrogenous fertilizers under pot culture experiment
46. Growth stage Cultivar
CH4 emission rate
(mg.pot-1h-1) (mg.g-1 plant.h-1)
Tillering
Booting
Flowering
Ripening
IR-72
IR 65598
Chiyonishiki
IR-72
IR 65598
Chiyonishiki
IR-72
IR 65598
Chiyonishiki
IR-72
IR 65598
Chiyonishiki
0.380
0.304
0.239
1.268
0.707
1.161
1.648
0.979
1.826
2.252
0.664
1.775
0.042
0.040
0.036
0.095
0.061
0.097
0.080
0.065
0.108
0.077
0.032
0.119
Table 9: Methane emission rate of three rice cultivars at four growth
stages
West Bengal Mandal et al. (2012)
52. Fig. 12: Methane emission SRI and Modified SRI.
New Delhi Niveta et al., 2013
53. Fig. 13: Nitrous oxide emission SRI and Modified SRI.
New Delhi Niveta et al., 2013
54. Table 13: Methane production in different crop establishment
Method of
establishment
Methane efflux (mg plant-1 day-1)
30 DAT 60 DAT 90 DAT 120 DAT Mean
Transplanted
paddy
0.71 6.13 6.25 6.02 4.77 (100 %)
SRI 0.54 4.24 4.42 4.08 3.32 (69.60 %)
55. Source of nutrient
Total methane production
(kg ha-1)
2012 2013 Pooled
RDF (100 % N through urea) 23.89 26.95 25.42
RDF (100 % N through neem coated urea) 22.30 24.79 23.55
50 % N through paddy straw incorporation + 50 %
N through urea + Rec. P & K
31.01 34.22 32.62
50 % N through FYM + 50 % N through urea +
Rec. P & K
26.83 29.88 28.35
50 % N through In-situ green manuring
(Sunhemp) + 50 % N through urea + Rec. P & K
28.72 32.08 30.40
Table 14: effect of source of nutrient on methane production (Kg ha-1)
from SRI
UAS, Bengaluru Suresh Naik (2014)
57. Fig. 11: Global warming potential of transplanted and direct seeded rice
Punjab Pathak et al. (2013)
58. Fig.12: GWP of rice-wheat system under different conservation
technology
Note: GWP: Global warming Potential, FP-Farmer practice, Mid drain: Mid
season drainage, ZT: Zero-tillage, DSR: Direct seeded rice
Punjab Pathak et al. (2013)
59. Table 15: Comparison of CH4 emission under different
cultivation methods
Method of
establishment
Range of CH4
fluxes
(gm-2 d-1)
CH4
emission
factor
(gm-2 d-1)
Comparison
(%)
Min Max
Dry DSR -0.031 0.59 0.17 64.0
Wet DSR 0.003 0.66 0.23 84.0
Transplanting
(30 days seedlings)
0.011 0.76 0.31 94.6
Korea Soon kuk et al. (2014)
60. Canada Snyder et al. (2010)
Fig.13: Effect of nitrogen (Urea) on N2O emission in DSR
61. Table 16: Methane emission and net reduction (%) in rainfed
rice
Source of Nutrients
Methane emission
(Kg ha-1)
Net Reduction (%)
Rice straw 92.10 -
Compost 65.87 34.13
Azolla 68.45 25.3
Nitrate inhibitor 61.66 33.1
Tablet urea 45.47 50.62
Cuttack (Orissa) Wassmann et al. (2011)
62. Fig. 13: Effect of butachlor on methane efflux from direct seeded rice
64. Table 17: Methane and Nitrous oxide emission from
different rice culture
Rice culture
Methane emission
(Mg plant-1 day-1)
N2O emission
(µg plant-1 day-1)
Transplanted rice 24.0 9.14
SRI 21.8
11.9
Aerobic rice 12.31 14.47
Bengaluru Jayadeva et al,. 2009
65. Source of nutrient
Total methane
production (kg ha-1)
2012 2013 Pooled
RDF (100 % N through urea) 20.80 23.11 21.95
RDF (100 % N through neem coated urea) 18.73 20.56 19.56
50 % N through paddy straw incorporation + 50 % N
through urea + Rec. P & K
27.02 31.10 29.06
50 % N through FYM + 50 % N through urea + Rec. P &
K
22.87 25.31 24.09
50 % N through In-situ green manuring (Sunhemp) + 50
% N through urea +
Rec. P & K
24.82 27.77 26.29
Table 18: Effect of source of nutrient on methane production (Kg ha-1)
from Aerobic Rice
UAS, Bengaluru Suresh Naik (2014)
66. Table 19: Methane and Nitrous oxide emission by aerobic
rice as influenced by fertilizer treatment
Germany Sebastain, D. (2015)
Fertilizer
treatment
CH4 (kg CH4 h-1 season-1) and N2O (kg NO2
-1 seaon-1)
emission (pooled data: 2012-14)
Zero-N Conventional Site specific
CH4 N2O CH4 N2O CH4 N2O
Sampling period
(87 d)
4.66 0.57 4.84 1.04 5.2 1.82
Cropping Period
(109 d)
4.96 0.66 5.41 1.57 5.28 2.27
69. Fig.1 Potential Impacts of
climate change
Potential
Global
Climate
Change
Impacts
Rise in
temperature
Changes in
Rainfall
Sea Level Rise
Agriculture
Health
Forest
Water
Resources
Coastal Area
Land
Weather Related
mortality
Infectious Diseases
Respiratory problems
Crop Yields
Irrigation Demands
Forest Composition
Forest Health
Water Quality
Water Supply
Competition for Water
Erosion of beaches
Inundation of
coastal land
Loss of Habitat
Biodiversity Erosion
70. WAY FORWARD Climate Change and agriculture are inseparably
linked globally, both affecting and influencing each other.
Climate Change influences the crop yield and quality, fertility
status of soil and may pose a serious threat to food and nutritional
security.
The challenge for Indian agriculture is to adopt to potential changes
in temperature and precipitation and to extreme events without
compromising productivity and food security.
Though the efforts are going on to develop strategies to mitigate
the negative impact of Climate Change and research in new
directions are being carried out, more emphasis is required to make
sufficient investments to support Climate Change adaptation and
mitigation policies, technology development and dissemination of
information19 .
71. Mitigation options for
methane emission from
submerged rice soils
Changing
of rice
cultivation
system
Use
of inorganic
fertilizers
Terminal
electron
acceptors Maintaining
The higher
redox potential
Cultural
practicesWater
management
Use of rice varieties
Fig Important mitigation options for methane emission in
submerged rice soils