1. Impact of Climate Change on Rain-fed Rice Production in
Mekong River Delta and Affect on Farmer’s Livelihood
Nguyen Thi Hien Thuan
Sub-Institute of Hydrometeorology of South Vietnam
Suppakorn Chinvanno
SEA START RC
AIACC AS 07

2. CONTENTS Objectives Scope and method of study Main activities
Major findings

3. Objectives:
To understand the long term impacts of climate change on rice production in Mekong River Delta
To understand the vulnerability of community in the Mekong River Delta from impacts of climate change on rice production
To seek adaptation option(s) on such impacts to minimize vulnerability to the community

4. Scope and Method of study:
Analysis of impact of climate change on rice production
To simulate the yield of rain-fed rice production in the MRD under different climate scenarios (1.5 x CO2 and 2 x CO2) using DSSAT crop modeling technique.
Climate scenarios with outputs from CCAM regional climate model, are generated to analyze the change of rice yield in the region.
Produce climate risk map of rice production by comparing the change in the yield of rice from observed average actual yield and the result from the simulation.

5. Scope and Method of study:
Assessment on climate risk at the commune level
Conduct field survey
Analyze how the community livelihood may depend on the rice production
Analyze the capacity to cope with disaster
Produce vulnerability map – consider the community which have household income reduction beyond “acceptable” level and does not have sufficient alternate source of income to maintain their livelihood.

6. Main Activities: Phase 1: Phase 2:
Simulation of the yield of rice production using DSSAT 4.0. Need data from VN as input to the model include: crop management data, soil properties, weather data (rainfall, maximum temperature, minimum temperature, sunshine hours).
Phase 2:
Field survey assessment to cover 4 provinces of the MRD of Viet Nam: Long An, Can Tho, Dong Thap, An Giang. Coverage of assessment in each province covers 2 communes per district and 4 districts per province.

7. 4 provinces: Long An, CÇn Th¬, §ång Th¸p, An Giang
Study areas
4 provinces: Long An, CÇn Th¬, §ång Th¸p, An Giang
- Located in the MRD in VN
Rice production is a major agricultural activity, >1 mil ton of rice product per year
Rice production is highly affected by climate factors (floods/inundations, droughts, inappropriate rains, …

9. Impacts of Climate Change on Rice Production
Climate Scenarios: CCAM model outputs (R, Tmax, Tmin, SRAD) at different CO2 concentration
1.0xCO2: as a baseline
1.5xCO2:
2.0xCO2 : 2066 – 2075
The simulation has been made for each year of the 3 scenarios. The typical extreme cases have been selected: dry/median/wet years

10. Impacts of Climate Change on Rice Production: DSSAT crop model simulation results
DSSAT software has been used for rice yield simulation for 1978 – 2002 for each of 4 provinces with:
- 2 rice types: IR64, IR66 (short-term rice ~ days)
- 3 soil types: Alluvium, shallow acid sulfate soil, deep acid sulfate soil
- Irrigated and non-irrigated crops
Climate Scenarios: CCAM model outputs (R, Tmax, Tmin, SRAD) at different CO2 concentrations
1.0xCO2: as a baseline
1.5xCO2:
2.0xCO2 : 2066 – 2075
The simulation has been made for each period of the 3 scenarios. The typical extreme cases have been selected: dry/median/wet years

12. CCAM rainfall scenarios Dry/wet year for 1. 0CO2 (upper) 1
CCAM rainfall scenarios Dry/wet year for 1.0CO2 (upper) 1.5CO2 (middle), 2.0CO2(lower)

13. Change in rice yield in different CC scenarios (average value for each scenario compared with baseline)

14. Rice yield anomalies of different scenarios (%)
Winter – Spring
1.5CO2
2.0CO2
Dry
Med
Wet
AN GIANG 4 -2 5 -7 -9
CAN THO -6 14 2
-14 1 -8
DONG THAP 12
-10
LONG AN -5 13 7

15. Rice yield anomalies of different scenarios (%)
Summer-Autumn
1.5CO2
2.0CO2
Dry
Med
Wet
AN GIANG
-10 -2 10
-42
-57 21
CAN THO -9 11
-27
-24 2
DONG THAP 3 8
-34
-53 -5
LONG AN
-16 9
-31
-26 -3

16. Rice yield anomalies of different climate scenarios

17. Change in rice yield in different CC scenarios
Winter-Spring rice
Dry Median Wet
1.5xCO2 scenario
2.0xCO2 scenario

18. Change in rice yield in different CC scenarios
Summer-Autumn rice
Dry Median Wet
1.5xCO2 scenario
2.0xCO2 scenario

19. Field Survey
The survey was conducted at 4 provinces of MRD: Long An, Can Tho, Dong Thap and An Giang x 4 districts x 2 communes, total of 40 agricultural officials + 64 farmers.
Information collected from survey includes:
General household condition (Total land area; crop area – 1 crop, 2 crops, 3 crops per year; rice growing area; population, labour,…)
Household economic conditions (total income, income from rice production, other income sources, Hh expenditure, surplus revenue, land ownership,…)
Climate risk groups (based on multiple indicators)
Coping capacity & strategy

20. Measured/Calculated as
Climate Risk Analysis: Measurement Multi-criteria, multiple indicators
Index
Weight
Measured/Calculated as
Value Scoring
Household Economic Condition 1
Sufficient household productivity
Total HH income / Total HH Expenditure
1 - 3 2
Surplus household revenue
Percentage of (HH income – HH expenditure) / HH Expenditure 3
Self-sustain rice consumption
Produce sufficient rice for own consumption – Yes / No
1 - 2 4
Land ownership
To indicate the critical production resource – Yes / No
Rice Production Dependency 5
Sustainable livelihood without rice production
Ratio of Total extra income / Total fixed expenses
2 - 6 6
Level of livelihood dependency on rice production
percentage of household fixed expenses that rely on rice income: (Total household expenditure - Extra income)/Rice income * 100
Coping Capacity 7
External financial support mechanism
Accessible to external loan to support rice production – Yes / No
2 - 4 8
Alternate source of income
Sufficient alternate source of income to maintain livelihood
Possible range of vulnerability value scoring
12 to 32

21. Climate Risk Analysis
Climate risk groups: value Scoring: 12 – 19 = Low vulnerability (13 Households) >19 – 26 = Moderate vulnerability (34 Households) > 26 – 32 = High vulnerability (17 Households)

22. Climate Risk
Low vulnerable farmers (13 Households) Moderate vulnerable farmers (34 Households) High vulnerable farmers (17 Households)
Farmer's experienced climate variability that affects livelihood and rice production 
Drought in winter-spring crop
Dry spells in rainy season
Prolonged rain
Too sunny in dry season, drought
Long-lasting flood
Extended flooding areas
Deep inundation
Low vul. 3 2 12 9 7 5
Mod vul 6 21 10 22 13
High vul 8

23. Experience in coping with climate change to reduce adverse impacts
Coping strategies
Experience in coping with climate change to reduce adverse impacts
Normally flooded
Deeply flooded
Long-lasting flood
Drought for long time
Rain for long time
Low vulnerable group
13 Households
pumping, embankment, drainage
pumping, drainage canals, dredging,,
fish breeding
buy drying machine
short term rice, appropriate crop
earlier harvest
out of control

24. Coping strategies
Experience in coping with climate change to reduce adverse impacts
Normally flooded
Deeply flooded
Long-lasting flood
Drought for long time
Rain for long time
Moderate vulnerable group 34
Households
Pumping, embankment, drainage
pumping, more irrigation canal, dredging
short term rice,
appropriate crop
2 crops,
appropriate
crop and breed
other crops,
Drought-
resistant
Varieties
More solid
stem breed
Machinery
intervention
fertilize
buy drying machine
earlier
sowing
harvest
no crops,
unable to cope

25. Coping strategies
Experience in coping with climate change to reduce adverse impacts
Normally flooded
Deeply flooded
Long-lasting flood
Drought for long time
Rain for long time
High
Vulnerable
group 17
Households
pumping, embankment, drainage
irrigation, drainage,
canal and river dredging
embankment.
strengthning canal system
reducing water
reduce No of crops/yr,
change sowing time
earlier harvest ,
later sowing
Short-term rice,
appropriate crop,
appropriate production zones
short term rice
Drought-
resistant
varieties
unable coping
live with flood

26. CONCLUSIONS
Rice production in the MRD tends to reduce in the future from impacts of CC. The adverse impacts are more serious in extreme years, especially in dry conditions.
The multi-criteria technique is used in the assessment of rain-fed farmer vulnerability to climate impact. A method has been set up to categorize vulnerability groups, their socio-economic condition and the sensitivity to climate impact on rice production.
Farmers in the Mekong River delta area seems to have sufficient capacity to cope with the impact of climate change on rice production due to the high productivity level and existing coping mechanism. However, due to heavy dependency on rice production and the lack of CC awareness, a large number of faming households are moderately –highly vulnerable to CC.

27. Thank You for your Attention!
Impact of Climate Change on Rain-fed Rice Production in
Mekong River Delta and Affect on Farmer’s Livelihood
AIACC AS 07