5.5.4. Adaptation Options
Human societies in rangelands would have to adapt to changes in climate, especially
temperature and water availability. The SAR concludes that the lack of infrastructure
and investment in resource management in many countries dominated by rangelands
makes some adaptation options problematic (Allen-Diaz, 1996) but also makes
these areas more sensitive to impacts of climate change (Gitay and Noble, 1998).
Nevertheless, some adaptation options are available for many of the rangelands.
Specific examples of the interaction between climate change and management
decisions may be highlighted better at the regional level. For example, in Australia,
Pickup (1998) found that substantial shifts in rainfall have occurred over the
past 100 years. If climate change results in further shifts in rainfall patterns,
the major impacts are likely to be related to increased climate variability.
Pastoral management decisions in these rangelands tend to be taken over the
short term; wetter periods generate unrealistic expectations about land use
and high stocking rates, which drier periods are unable to support. This has
and would lead to land degradation.
5.5.4.1. Landscape Management
Rangelands consist of a mosaic of various ecosystem types (WRI, 2000) with
soil and water processes as well as associated nutrient cycles that operate
at the landscape or regional scale (Coughenour and Ellis, 1993). Human use of
rangelands often affects landscape processes (e.g., water flow, soil erosion)
and changes in processes such as productivity, decomposition, and fire. Thus,
possible future adaptation options might have to be sought at the landscape
level (Aronson et al., 1998) and over long time frames (Allen-Diaz, 1996). Because
many rangelands are in semi-arid and arid parts of the world, actions to reduce
destruction of the soil crust (which are important for soil stabilization and
nitrogen fixation) and thus land degradation are extremely important. These
actions could include adjustment in the time and intensity of grazing (Belnap
and Gillette, 1998). Restoration of degraded soils has vast potential to sequester
carbon in soil and aboveground biomass (Lal et al., 1999), although restoration
could be costly (Puigdefabregas, 1998).
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