Climate Change and Rice Production

Tran Dang Hoa Faculty of Agronomy Hue University of Agriculture and Forestry Vietnam

•  4 millions ha •  Main regions: - Red river delta - Central - Mekong delta

Climate Change Effects Relevant for Rice Production

Climate change in Vietnam

Sea level rises 2.5-3 cm/ 10 years in the last century

Vietnam sea level rise (SLR, cm) as compared with 1980-1999

Scenarios Emission 2020 2050 2100 B1 Low 11 28 65 B2 Medium 12 30 75 A2 High 12 33 100

Red river delta: land area will be under water if sea level rise of 1m

Mekong river delta: land area will be under water if sea level rise of 1m

21.0

21.5

22.0

22.5

23.0

1974 1979 1984 1989 1994 1999 2004

2 1

3 4

OC

Year

Variability (1), climatological average (2), moving average (time step - 11 year) (3) and linear trend (4) of

Temperature at A Luoi station.

Annual temperature

Average temperature increase 0.10C/10 years.

Average temperature of some months in summer is increase 0.1- 0.30C/ 10 years.

Temperature increase

Vietnam Temperature increased as compared with 1980-1999

Scenarios T(0C) 2020 2050 2100 A2 High

Increase 0.5 1.5 2.8

B1 Low Increase

0.3 0.8 1.6

• Rainfall is decrease in dry season, but increase in raining season.

• Heavy raining causes strong flood frequently

1000

2000

3000

4000

5000

1974 1979 1984 1989 1994 1999 2004

2 1

3 4

mm

Year

Variability (1), climatological average (2), moving average (time step - 11 year) (3) and linear trend (4) of

August-December rainfall at A Luoi station.

Rainfall of Aug.-Dec.

• Typhoon - Non rule - moves to the south.

•  Climate change mitigation is any action taken to permanently eliminate or reduce the long-term risk and hazards of climate change to human life or property

•  Climate change adaptation refers to the ability of a system to adjust to climate change (including climate variability and extremes) to moderate potential damage, to take advantage of opportunities, or to cope with the consequences.

Action plan on rice production

Mitigation/Adaptation

GHG from Agriculture

2050 , GHG from agriculture will be

increased 30% FAO, April 11, 2014

Mitigation

•  Agriculture causes about 25 % global anthropogenic CO2 emissions, 65-70 % of CH4, and 90 % of N2O emissions

•  Rice paddies contributing about 12% to global CH4 emissions (second largest after cattle livestock)

•  Global Warming Potential (GWP): CH4 – 25 times higher than CO2 N2O – 298 times higher than CO2

Climate Change Mitigation within the rice agricultural sector

http://www.ibp.ethz.ch (modified)

• Rice varieties

• Fertilizer

• Water management

GHG from Agriculture sectors in Vietnam (MONRE, 2000)

CO2 Equ (MT) % Rice Field 37.4 57.5 Live stock ( Fermentation &Manure)

11.1 17.2

Soils 14.2 21.8 Burning field 0.59 0.9 Crops Residues Burning 1.70 2.6 Total 100

Quang Nam province LUCCi project 6 seasons 2010 - 2013

Hue province MIRSA project 2014

GHG experiments on paddy fields

PI to complete flowering

grain filling

Maturity Late tillering

Early tillering

transp recovery

Field water depth (Cm)

-10 -5 0 2.5 5

10

-20

-15

0 10 20 30 40 50 60 70 80 90 100 110

CF

AWD soil surface

DAT

flowering

Alternate Wetting and Drying (AWD)

Safe AWD: - 15 cm

Site-specific nutrient management

A standardized leaf color chart (LCC)

•  Applying nutrients as and when needed

•  Adjusting nutrient application to crop needs in given location and season

GC: SRI 8610C

Gas analysis

GC setting, 2011

a a a a

0

2

4

6

Nam Phuoc Dai Loc

Yiel

d to

n ha

-1

Summer – Autumn 2011

CF AWD

a a a a

0

2

4

6

Nam Phuoc Dai Loc

Yiel

d to

n ha

-1 Winter - Spring 2011 - 2012

CF AWD

No difference in yield of different water management practices

LUCCi project

41.9% reduction 44.3%

reduction

0

2

4

6

8

10

12

14

16

Summer - Autumn 2011

Winter - Spring 2011 - 2012

GM

P to

n h

a-1

CF AWD

33.6 % reduction

31 % reduction

0

1

2

3

4

5

6

7

8

9

Summer - Autumn 2011

Winter - Spring 2011 - 2012

GW

P to

n ha

-1

CF AWD

Dai Loc Nam Phuoc

Global Warm Potential

Yield (ton/ha)

b b

a

A A A

0

2

4

6

8

10

CF ADW AWDS Treatment

ton ha-1 Potential yield Grain yield

MIRSA project

Methane fluxes

0 200 400 600 800

1000 1200 1400 1600 1800

0 10 20 30 40 50 60 70 80 90 100 110

CF AWD AWDS

CH4 mg m-2 d-1

-250 -200 -150 -100

-50 0

50 100 150

0 10 20 30 40 50 60 70 80 90 100 110

Daily average water level (mm)

DAS

Nitrous oxide fluxes

2.40 3.40 4.40 5.40 6.40 7.40 8.40

0 10 20 30 40 50 60 70 80 90 100 110

CF AWD AWDS

MDL

N2O mg m-2 d-1

N applied N applied

-250 -200 -150 -100

-50 0

50 100 150

0 10 20 30 40 50 60 70 80 90 100 110

Daily average water level (mm)

DAS

CH4

5

105

205

305

405

505

605

CF AWD AWDS

CH4 kg ha-1

22% reduction 15% reduction

104 days

2.50

2.55

2.60

2.65

2.70

2.75

2.80

2.85

2.90

2.95

3.00

CF AWD AWDS

N2O kg ha-1

MDL

104 days

N2O

Seasonal cumulative gas emission

Aerobic rice system

Treat rice like any other (irrigated) crop: No puddling, no standing water, aerobic soil

Adaptation: IRRI projects

Salinity tolerance variety

Cropping  System  &  Management  in  coastal  zones  

Calendar

Wat MgtWat Source

CalendarWat MgtWat Source

Calendar 1

Calendar 2

= Land preparationGrav Irrig = gravity irrigation P Irrig = Pump irrigation St Wa = Stored Water

No salinity control

Main season rainfed rice

Brackish water Shrimp Main season rainfed rice

Salinity control + irrigation

water

Salinity control;

no irrigation

water

Summer Autumn Autumn Winter

Salinity

SalinityWinter Spring Summer Autumn Autumn Winter

P irriRiver Wat St WSt W

Grav IrriPump IrrigationRiver waterRver+St WatRiver W

Rainfed Grav Irrig

Leaching Rainfed Grav Irrig P Irr

Salinity

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

DEC JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC

Saline period Low/non-saline

Preparation

Shrimp

Leaching

Rice Wat Stor

Leaf, tiller and root development

Panicle development

Grain filling Pollination

LOW HIGH MEDIUM

Sensitivity to Heat Stress

MINIMUM

MAXIMUM

0

10

20

30

40

50

JAN

FEB

MA

R

APR

MAY

JUN

JUL

AU

G

SEP

OC

T

NO

V

DEC

Vegetative

Flow

erin

g G

rain

Fi

lling

Tem

pera

ture

(oC

)

Rice Crop

Seasonal calendar

Conclusion

Climate Change Mitigation: Rice systems have to become more efficient in terms of… •  Water use •  Fertilizer uptake •  Harvest index

Adaptation: Rice systems have to become more resilient to… •  Drought •  Submergence •  Salinity •  Heat waves By •  Germplasm development •  Crop management •  Cropping system •  Resource management and Structures

QUESTION to Restructure Program Sources Measures Need

- Too much water used for rice -  Too low efficiency of inputs (fertilizers, pesticides, waters) -  Soil degradation -  Low C-soil sink -  Increase GHG

-  Saving water=> precision irrigation system - Changes the way of rice cultivation (less input. less w a t e r u s e s . = > h i g h efficiency.) -  Re-use rice/ crop residues; mulching/ Bio-char/ Min tillage -  Added values for all agriculture products & by products

-  N e w Technology -  New behaviors -  P r e c i s i o n agriculture -  C-sequence

- Low comparative productivity -  Uncertainly income

-  Replace Rice by other crops with reversible ways - Added values for all Rice products & by products

-  New techniques? -  Multiple cropping -  Investment -  New Marketing Approach

-  Sea level rise -  Weather uncertainty -  Salinity - Drought/ - Flooding - Heat/cool

-  Physical and biological ways -  Inter-field damps -  Multiple cropping -  Mixed cropping

-  Modelling -  New behaviors -  Good prediction -  Good investment design -  Useful Information/data

Thanks for your attention