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.
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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