11.2.1 Adaptation Technologies
Adaptations - such as changes in crops and crop varieties, improved water management
and irrigation systems, and changes in planting schedules and tillage practices
- will be important in limiting negative effects and taking advantage of beneficial
changes in climate. The extent of adaptation depends on the affordability of
such measures, particularly in developing countries: access to know-how and
technology, the rate of climate change and biophysical constraints such as water
availability, soil characteristics and crop genetics. (SPM, SAR of IPCC WG II,
1996)
Many adaptation opportunities suitable for climate change have already been
applied by farmers. Table11.1 provides a list of
currently available adaptation opportunities that can be applied at the farm
or farmer community level. Most available options take advantage of the general
flexibility of agricultural systems related with the short management cycles
involved. It is likely that autonomous adjustment by farmers will continue to
be important as climate changes, provided that farmers have access to the right
information and tools. However, some agricultural systems are less flexible,
for example because they are constrained by soil quality or water availability,
or because they face economic, technological, institutional or cultural barriers.
In such cases, autonomous adjustments may not be implemented in time because
of lack of awareness (of both problems and solutions), and anticipatory planned
adaptation would be required to provide the right conditions (i.e., information
and tools) to farmers for autonomous adjustment (Klein and Tol, 1997).
Anticipatory strategies for adaptation to climate change and climate variability
aim to increase flexibility so as to allow the type of adjustments shown in
Table 11.1. For example, increasing the variety of
crops may require the introduction of new knowledge and machinery to a farming
community. However, as climate changes, the technologies listed in Table
11.1 may not be sufficient, and the need may arise for the development of
new technologies to allow farmers to cope better with anticipated climate-change
impacts, and to reduce the costs of adaptation (Klein and Tol, 1997).
| Table 11.1 Examples of adaptation
opportunities to climate-change impacts on agricultural systems (Smit, 1993). |
| Response strategy |
Adaptation options |
| Use different crops or varieties to match changing water supply and temperature
conditions |
- Conduct research to develop new crop varieties
- Improve distribution networks
|
| Change land topography to reduce runoff, improve water uptake and reduce
wind erosion |
- Subdivide large fields
- Grass waterways
- Land leveling
- Waterway-leveled pans
- Bench terracing
- Tied ridges
- Deep plowing
- Roughen land surface
- Use windbreaks
|
| Introduce systems to improve water use and availability and control soil
erosion |
- Low-cost pumps and water supplies
- Dormant season irrigation
- Line canals or install pipes
- Use brackish water where possible
- Concentrate irrigation water during peak-growth period
- Level fields, recycle tailwater, irrigate alternate furrows
- Drip-irrigation systems
- Diversions
|
Change farming practices to conserve soil moisture and
nutrients, reduce runoff and control soil erosion |
- Conventional bare fallow
- Stubble/straw mulching
- Minimum tillage
- Crop rotation
- Contour cropping to slope
- Avoid monocropping -
- Chisel up soil clods
- Use lower planting densities
|
| Change timing of farm operations to better fit new climatic conditions |
- Advance sowing dates to offset moisture stress during warm period
|
|