Adaptive cycle and Panarchy

1. Adaptive cycle and Panarchy

2. Adaptive cycle of recovery (succession) after disturbance Complex system undergoes change through ‘adaptive cycle’ r=growth (pioneer; stand initiation) K=carrying capacity (competition, niche specialization) (mature to old-growth) Ω=release, new opportunities (disturbance) α=re-organization and recovery (new forest seeds in) Gunderson & Holling 2002

3. Four stages of adaptive cycle 1) Exploitation: rapid expansion, e.g., population grows. 2) Conservation: population reaches carrying capacity and stabilizes for a time. 3) Release: population declines due to a competitor, or changed conditions 4) Reorganization: certain members of the population are selected for their ability to survive despite the competitor or changed conditions that triggered the release.

4. Adaptive cycle: four stages r K Ω α Ω α r K

5. Three properties of adaptive cycle Potential: the number and kinds of future options available (e.g. high levels of biodiversity provide more future options than low levels) Connectedness: the degree to which a system can control its own destiny through internal controls, as distinct from being influenced by external variables Resilience: how vulnerable a system is to unexpected disturbances and surprises that can exceed or break that control. The adaptive cycle is the process that accounts for both the stability and change in complex systems.

6. There are ‘discontinuities’ in variables of interest Discontinuities determine dominant scales

7. Adaptive cycles occur at multiple discontinuous scales in natural ecosystems Temporal scale Spatial scale

8. Panarchy • A term adopted to better represent complex adaptive systems than ‘hierarchy’ • Hierarchy describes “top-down rule” • Panarchy refers to a specific form of governance or rule (archy) that would encompass (pan) all others

9. What is panarchy? “The term [panarchy] was coined as an antithesis to the word hierarchy (literally, sacred rules). Our view is that panarchy is a framework of nature's rules, hinted at by the name of the Greek god of nature, Pan.” Lance Gunderson and C. S. Holling, Panarchy: Understanding Transformations in Systems of Humans and Nature, Island Press, p.21, 2001.

10. Panarchy: all-encompassing nested set of adaptive cycles operating at discrete scales (Gunderson and Holling 2001).

11. These cycles connect with cycles ‘above’ and ‘below’ them in the hierarchy: “Revolt" – this occurs when fast, small events overwhelm large, slow ones, as when a small fire in a forest spreads to the crowns of trees, then to another patch, and eventually the entire forest “Remember" – this occurs when the potential accumulated and stored in the larger, slow levels influences the reorganization. For example, after a forest fire the processes and resources accumulated at a larger level slow the leakage of nutrients, and options for renewal draw from the seed bank, physical structures and surrounding species that form a biotic legacy. 7/10

12. Panarchy predicts discontinuities in adaptive cycles across scales

13. Three Core Properties of Complex Systems that follow Panarchy Theory Allen, Craig R., et al. "Panarchy: Theory and Application." Ecosystems 17.4 (2014): 578-589.

14. Cup-and-ball model: changes to new stability domain through shift in variables or parameters e.g., variable=species composition e.g., parameter=climate

15. Global to arctic Mann et al. Polar amplification Chapman and Walsh

16. Permafrost is thawing in many places, not just southern margins

17. Four mechanisms affect permafrost thaw: • Active layer thickening • Talik formation • Erosion • Thermokarst development Positive feedback to atmospheric GHGs Schuur et al. 2008

18. Mineral deposit, Siberia Cryoturbated soil, thin peat, Alaska Frozen peat, Canada, Siberia Schuur et al. 2008

19. Melting permafrost Hudson Bay, Canada Science Daily, Sept 2, 2008

20. Both the variables and the parameters are changing in the Arctic e.g., variable=species composition e.g., parameter=climate

21. IPCC FAR projected global warming

22. Mean Annual Temperature and Precipitation Predictions for BC

23. Four Impacts to Forests 1. Reduced snow pack 2. Increased forest fires 3. Forest dieback and species migrations 4. Forests shifted from net CO2 source to sink

24. 1. Dramatic decline in snowpack by 2040 http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch11s11-5-3-5.html

25. 2. Increasing area burned annually in Canada

26. 3. Massive shifts in forest composition http://cfcg.forestry.ubc.ca/projects/climate-data/climatebc-and-bioclimatic-envelope-modelling/

27. 4. Changed from CO2 sink to source

28. New study shows declining productivity and carbon sequestration in Canadian boreal forest NASA, Dec. 2011 Pan, PNAS, 2012

29. Potential Impacts of Climate Change in Forests BC Ministry of Forests • Increased forest fire frequency and severity due to warming and drying. • Increased disturbances due to insects and disease. • Potential ranges of species will move northward and upward in elevation. • New assemblages of species will occur in space and time. • Species may be unable to move into areas of suitable climate due to barriers to movement, slow migration rates, unsuitable growing substrate or lack of habitat.

30. Summary • Complex adaptive systems are inherently stable • Stable systems change but are homeostatic, like a dancer • Stables systems have resistance, where small disturbances are contained, and resilience, where the system returns to the same stability domain • Complex systems change through adaptive cycles • Adaptive cycles and panarchy are stabilizing characteristics • Positive feedbacks and crossing tipping points can lead to loss of stability • Climate change could cause instability • Maintaining complexity will be crucial