mekong arcc - climate change impact and adaptation study: natural and agricultural systems
TRANSCRIPT
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 1a
Climate changes
Hydrological changes
Agricultural zones
Ecological zones
Species “zones”
Commercial
crops
Subsistence
crops
Traditional
crops
Aqua-
culture
Crop wild
relatives NTFPs Wild fish
catch
Adaptation options
Wildlife Live-
stock
Assessing climate change threats to agriculture and
subsistence livelihoods
Agro-ecological systems and climate change vulnerability continuum
3
4
Transition from subsistence to commercial agriculture
Intermediate Commercial
Land consolidation
Increased capital
intensity
Small holdings
Labourintensive
Low capital
intensity
Commercial farms and
plantations
Subsistence
Industrialization, rural-urban migration
Climate change shifts
Regular climate
1. Geographic shifts – change in area of suitability
2. Elevation shifts (for highly restricted habitats and
species) – change in (i) location and (ii) elevation
3. Seasonal shifts – change in (i) yields, (ii) cropping
patterns
Extreme events
4. Extreme event shifts
Micro – eg flash flooding and soil loss in uplands
Macro – eg saline intrusion in Delta; cyclone landfall
Geographic shift
Paddy rice and
commercial crops
Shift in zone of suitability
for habitat and crops Original extent of
natural habitat
Remaining
natural habitat
pockets
Subsistence crops and NTF
collection
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
Climate change hot spot -
rainfall
Climate change hot spot -
Temperature
Industrial and commercial
crops and climate change
hotspots
Lowland rice
Se San Basin – existing land use suitability
upland rice
Se San Basin – existing land use suitability
rubber
Se San Basin – existing land use suitability
Coffee (coffea canephora)
Se San Basin – existing land use suitability
cassava
Se San Basin – existing land use suitability
Maize
Se San Basin – existing land use suitability
Climate change (precipitation in 2050) in the Se San catchment
Climate change (temperature in 2050) in the Se San catchment
Optimal growing conditions: Mean annual maximum
temperature
Sensitivity assessments: climate tolerances
Optimal growing conditions: mean annual precipitation
Sensitivity assessments: climate tolerances
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
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.
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.
Jeremy Carew-Reid
ICEM – International Centre for Environmental Management
www.icem.com.au