Impact of Climate Change on Rainfed Rice Production

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

CONTENTS 1. Objectives 2. Scope and method of study 3. Main activities 4. Major findings

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

Scope and Method of study: Analysis of impact of climate change on rice production ü To simulate the yield of rain-fed rice production in the MRD under different climate scenarios (1. 5 x CO 2 and 2 x CO 2) using DSSAT crop modeling technique. ü Climate scenarios with outputs from CCAM regional climate model, are generated to analyze the change of rice yield in the region. ü 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.

Scope and Method of study: Assessment on climate risk at the commune level ü Conduct field survey ü Analyze how the community livelihood may depend on the rice production ü Analyze the capacity to cope with disaster ü 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.

Main Activities: Phase 1: 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.

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, …

Impacts of Climate Change on Rice Production Ø Climate Scenarios: CCAM model outputs (R, Tmax, Tmin, SRAD) at different CO 2 concentration ü ü ü 1. 0 x. CO 2: 1980 - 1989 as a baseline 1. 5 x. CO 2: 2040 - 2049 2. 0 x. CO 2 : 2066 – 2075 Ø The simulation has been made for each year of the 3 scenarios. The typical extreme cases have been selected: dry/median/wet years

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: IR 64, IR 66 (short-term rice ~ 90 -95 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 CO 2 concentrations ü 1. 0 x. CO 2: 1980 - 1989 as a baseline ü 1. 5 x. CO 2: 2040 - 2049 ü 2. 0 x. CO 2 : 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

CCAM rainfall scenarios Dry/wet year for 1. 0 CO 2 (upper) 1. 5 CO 2 (middle), 2. 0 CO 2(lower)

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

Rice yield anomalies of different scenarios (%) Winter – Spring 1. 5 CO 2 2. 0 CO 2 Dry Med Wet AN GIANG 4 -2 5 -7 4 -9 CAN THO -6 14 2 -14 1 -8 DONG THAP 0 12 5 -10 -2 -10 LONG AN -5 13 7 -14 -5 -6

Rice yield anomalies of different scenarios (%) Summer. Autumn AN GIANG CAN THO DONG THAP LONG AN Dry -10 -9 3 -16 1. 5 CO 2 Med Wet -2 10 0 11 -10 3 8 9 Dry -42 -27 -34 -31 2. 0 CO 2 Med Wet -57 21 -24 2 -53 -26 -5 -3

Rice yield anomalies of different climate scenarios

Change in rice yield in different CC scenarios Winter-Spring rice Dry Median Wet 1. 5 x. CO 2 scenario 2. 0 x. CO 2 scenario

Change in rice yield in different CC scenarios Summer-Autumn rice Dry Median Wet 1. 5 x. CO 2 scenario 2. 0 x. CO 2 scenario

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

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

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)

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 Drough Dry spells Prolonged Too t in in rainy rain sunny in winter- season dry spring season, crop drought Longlasting flood Extended Deep flooding inunda areas tion Low vul. 3 2 12 9 7 2 5 Mod vul 6 7 21 10 22 7 13 High vul 2 5 8 5 12 8 8

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

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

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

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.

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