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SUSTAINABILITY RESEARCHFOR RANGELANDS
John E. Mitchell
Early understanding of rangeland sustainabilityfocused upon range condition
• Rangeland occupies 728 million acres – 40% of continental U.S.
• 75% of area has been depleted.• 95% of public domain has been depleted.
• Stocking rate – 17.3 million A.U.’s• Carrying capacity – 10.8 million• Original carrying capacity – 22.5 million
• > 580 million acres excessively eroding.
• But, 99% suitable for livestock grazing.
• It will take 50+ years of management to restore to withstand present use, and another 50+ years to restore to its original carrying capacity.
Senate Document 1991936
Rangelands have many values,both commodity and amenity related.
SUSTAINABILITY IS A 3-LEGGED STOOL
Criteria and Indicators:
EnvironmentalEconomicSocial and Legal
RESEARCH ISSUES
• Scale
• Thresholds
• Integrating the three legs
Scale in Ecological Observations
Grain = Resolving power of data.
Grain determines smallest entities that can be found in data.
Extent = highest level that can be
accessed.
If size of entity is larger than data (spatial, temporal), then associated attributes cannot be observed.
The larger the system,the longer the cycle time of unperturbed behavior.
From top to bottom of a hierarchy, there is a continuum of natural frequencies.
Frequency of Behavior
- Systems have particular characteristic frequencies.- Monitoring must accommodate frequency of a system’s scale.
Thresholds in Ecology
• Ecosystem Resilience
• Ecosystem Function
• Ecosystem Fragmentation
• Invasive Species
• Fire
Flora, C.B. 1999. Great Plains Research 9:397-419.
Sustainability as Expressed by Forms of Capital
• Capital has investment value.• Sustainability attained when combination of investments provide for future needs.
• Human Capital: Resources of individuals (education, leadership, values, etc.)
• Social Capital: Resources of community (mutual trust, reciprocity, collective action)
• Natural Capital: Resources from nature (clean air and water, soil, functioning ecosystems, diverse landscapes)
• Financial Capital: Measured in money (labor, structures, land, inventory, taxes)
Rangelands 17(6):199-214. Dec. 1995
Previous Sustainability Research
• Sustainable Biosphere Initiative (ESA)
• Forums in Ecological Applications
← SRM Symposium on Research Priorities
• SRM Task Group on Unity in Conceptsand Terms
• RMRS Assessment of Montreal Process
• “Sustainability Science” – a new discipline