Mekong ARCC Climate Change Impact and Adaptation Study for natural and agricultural systems

1. Mekong ARCC Climate Change Impact and Adaptation Study for natural and agricultural systems Jeremy Carew-Reid, ICEM – International Centre for Environmental Management www.icem.com.au September 2012 Hanoi

2. Assessing climate change threats to agriculture and subsistence livelihoods ICEM, 2012

3. Agro-ecological systems and climate change vulnerability continuum ICEM, 2012

5. Climate change shifts Regular climate • Geographic shifts – change in area of suitability • Elevation shifts (for highly restricted habitats and species) – change in (i) location and (ii) elevation • Seasonal shifts – change in (i) yields, (ii) cropping patterns Extreme events • Extreme event shifts • Micro – eg flash flooding and soil loss in uplands • Macro – eg saline intrusion in Delta; cyclone landfall

6. Geographic shift ICEM, 2012

7. Identifying climate change “hot spots” – i.e. highly vulnerable areas • High exposure: • significant climate change relative to base conditions • exposure to new climate/hydrological conditions • High sensitivity: • limited temperature and moisture tolerance range • degraded and/or under acute pressure • severely restricted geographic range • rare or threatened • Low adaptive capacity • Poor connectivity • Low diversity and tolerances • Homogenous systems

8. Climate change hot spot - rainfall

9. Climate change hot spot - Temperature

10. Industrial and commercial crops and climate change hotspots

11. Lowland rice

12. upland rice

13. rubber

14. Coffee(coffeacanephora)

15. cassava

16. Maize

19. Sensitivity assessments: climate tolerances Optimal growing conditions: Mean annual maximum temperature

20. Sensitivity assessments: climate tolerances Optimal growing conditions: mean annual precipitation

21. Trends in commercial crops with climate change • Rubber: Projected increases in temperature and precipitation would open upland areas for rubber cultivation. • Coffee plantations would suffer from changes in rainfall patterns and/or excess rainfall in the highland areas (especially Arabica). • Cassava: Relatively resistant to drought so would become a substitute in rain fed agricultural systems in drier areas BUT would have reduced suitability in high rainfall areas. • Sweet potato and key root crops not well suited to higher rainfall and soil moisture conditions and higher temperatures • Soybean would suffer from higher temperatures - shift to higher elevation may be required. • Bananas and mangoes: increases in temperature and precipitation would open upland areas for cultivation

22. Rice Rice cultivation and extreme flooding • Extreme floods will be more common in rice based production systems in Lowland Cambodia and the Mekong Delta. • Flood would have a larger impact where agriculture is intensified, with high yielding rice varieties less resilient to flood than traditional ones. • Investment in intensive rice cultivation will become more risky • Other commercial crops such as fruit and vegetables are less resilient to flood than rice.

23. Rice Rice cultivation and sea level rise • A 30 cm rise by 2050 with increased flood extent, depth and duration will result in a loss of 193,000 ha of rice area in the Mekong Delta. • Agriculture will be severely constrained by increased saline intrusion in the dry season and longer flood in the rainy season. • The double and triple cropping system commonly used in the Mekong Delta might not be possible. • Climate change will change the occurrence of plant disease and pests such as fungus and moulds, viruses, nematodes and a range of insects.

24. Thank youJeremy Carew-Reid, ICEM – International Centre for Environmental Managementwww.icem.com.au