Lessons Learned and Future Perspective David D Briske Ecosystem Science amp Management Texas AampM University Development Current Status and Lessons Learned Turkana Region NW Kenya Foundation of Range Management ID: 1009971
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1. Unpacking Equilibrium -Non-equilibrium Debate: Lessons Learned and Future PerspectiveDavid D. BriskeEcosystem Science & ManagementTexas A&M UniversityDevelopment, Current Status and Lessons Learned
2. Turkana Region NW Kenya
3. Foundation of Range ManagementA.W. Sampson 1919. Plant succession in relation to range management. USDA Bul. 791E.J. Dyksterhuis 1949. Condition and management of range land based on quantitative ecology. JRM 2:104
4. Ellis and Swift JRM1988Origin of Alternative Paradigm?
5. Non-equilibrium Persistent ModelEllis & Swift 1988
6. Implications of NEP ModelAntithesis of traditional range science that rejected:Density-dependent regulation of plant production by livestock.Concepts of carrying capacity and stocking rate.Ability of grazing animals to adversely impact rangeland resources. Behnke, Scoones & Kerven 1993
7. Motivation for NEPFailed African pastoral development programs were based on U.S. rangeland science.Need for programs originated from colonial narrative that pastoralism was backward and inefficient.NEP an attempt to explain why both the colonial narrative and U.S. range science were ineffective.Was pastoralism more effective than ranching?Ellis & Swift 1988
8. Motivation for NEP“the near universal failure of pastoral development suggests that something more fundamental is amiss” than technical incompetence of project managers or the intransigence of pastoralists - Ellis & Swift 1988.
9. NEP ChallengedEquilibrium asymptotically derived from extrapolation to larger scales (DeAngelis and Waterhouse 1987) . Minimize duality between biotic and abiotic drivers of rangeland dynamics (Sullivan 1996). Nonequilibrium models embraced with such enthusiasm that they were in danger of being misapplied just like equilibrium models Fernández-Giménez and Allen–Diaz (1999).
10. Functional HeterogeneityIllius and O’Connor 1999
11. Reinterpretation NEP ModelModel overlooked heterogeneity of forage resource use. Herbivores are coupled to a subset of ‘key’ resources accessible in dormant season i.e., biotic feedback. Herbivores uncoupled from abundant growing season forage resources. NEP emphasizes unique herbivore feedbacks with E and NE forage resources within landscapes.Key resource areas determine herbivore persistence within landscapes.Illius & O’Connor 2000Hempson et al. 2015
12. Lessons LearnedEquilibrial and nonequilibrial dynamics among plants and herbivores coexist within systems.Herbivore persistence is strongly influenced by functional resource heterogeneity.Biotic feedbacks are highly dependent upon spatial and temporal scale. Management and policy decisions are important in spite of high environmental stochasticity.
13. Continued MisconceptionsMultiple means of nonequilibriumE&S – loosely coupled plant-herbivore interactionsHolling – system with weak basin of attraction‘Generic’ – systems possessing stochastic behavior that makes management difficultConsistent with dynamic equilibriumEcological resilience describes this conceptAre rangelands ever exclusively non-equilibrial?
14. History of Rangeland ScienceNathan F. SayrePolitical EcologistGeography DepartmentBerkeleyUniversity Chicago Press 2017
15. NEP Previously Recognized in U.S.Weather rather than livestock appeared to be a major driver of vegetation dynamics in SW – Griffiths1910.Woody plant encroachment replaced grasslands even with the best grazing management.USFS viewed this as a threat to scientific range management, but not to successional theory.Succession was more a policy than ecological theory.Sayre refers to these misinterpretations as ‘blind spots’ in rangeland profession.
16. NEP - Blind Spot Made VisibleInescapable when U.S. range science was applied in semiarid, subsistence pastoral systems.Subsistence vs productionLimited cash economyIndigenous knowledgeLandscape mobilityInstitutional support
17. Do Other Blind Spots Exist?Professional mindset inconsistent with reality regarding rangeland function and value.Legacy or expediencyUnrecognized tradeoffsNew conditions/constraintsAlternatives unrecognizedKnown unknownsUnknown unknowns
18. BS #1: Livestock Supplementation Ellis & Swift – non-equilibrial conditions occur when herbivores are loosely coupled to rangeland forage.Supplementation promotes non-equilibrium conditions by reducing livestock coupling to rangeland forage.Replaces key resource areas and likely minimizes functional heterogeneityEnhances potential for rangeland degradation by artificially maintaining livestock persistenceMultiple examples exist to support this interpretation
19. BS #2: Provisioning Services OveremphasizedLegacy of Pinchot and progressive eraLimited production per unit areaLand values exceed agricultural potentialOther services taking on greater value
20. BS #3: Continued Historic Climate VariabilityWarmingDryingExtreme eventsMagnified 2050Appropriate response?Change # Consecutive Dry DaysNCA 2018
21. Climate Signal on Beef Cattle #s
22. BS #4: Ecological Knowledge SufficientDoes a unified model of rangeland ecology exist?Sufficient for 21st century rangeland stewardship?Management – sciencePolicy –scienceShifting societal valuesExternal driversGlobalized markets Anthropocene Epoch
23. Rangeland Systems FrameworkGlobal rangelands function as complex, adaptive social-ecological systems.Capacity to integrate social and ecological components.Recognize and assess trade-offs among provisioning and non-provisioning ecosystem services.How might this be best achieved?What may provide a sufficient catalyst for action?What organizations should be involved?
24. Future PerspectivesMichel de Nostradamus Les Propheties 1555 Rangeland ChangeRapid change 20th centuryAccelerating change in 21st centuryRole of rangelands for humanity?Long-term view seldom explored
25. Storylines of plausible future outcomesIdentification of major concerns or threats Assessment of critical drivers and uncertainties Development of potential scenario outcomes Analysis of implications and potential interventions Scenario Planning
26. ProvisioningServices Energy Extraction Grass Fed BeefFuture Climate Variability Historic Climate Variability Modern PastoralismNew Wild WestCulturalServicesRangeland Scenarios 2100