Ecosystem Resilience and the Adaptive Cycle

Transcription

1 Ecosystem Resilience and the Adaptive Cycle Brian D. Fath Towson University, USA International Institute for Applied Systems Analysis, Austria

2 Objectives System Sustainability Ecosystem dynamics Adaptive Cycle Collapse Response Adapting the Adaptive Cycle 5/26/2011 2nd Viennese Talks on Resilience Research & Networks

3 Why Ecology? I had not fully appreciated how much the ecological perspective can alter how we see the rest of the world Bob Ulanowicz A Third Window. Templeton Press. 5/26/2011 2nd Viennese Talks on Resilience Research & Networks

4 Open Systems Open systems connect to their environment through both inputs and outputs Environment Source System Sink 5/26/2011 Input-State-Output 2nd Viennese Talks on Resilience Research & Networks

5 Thermodynamically, Open Systems build and maintain order and organization by taking in high quality energy, using it, and passing degraded energy outside of the system. High quality Energy Input System (human or natural) Low quality Energy output (heat)

6 Simplified Ecosystem

7 Simplified Human System

8 Sustainability Constraints Input, Output, and System Dynamics Input? Output? System Input availability AND Output absorbance

9 VALUING THE EARTH Daly and Townsend (1993) Renewable resources should be exploited in a manner such that: 1) harvesting rates < regeneration rates; and 2) waste emissions < renewable assimilative capacity of the local environment.

10 Ecosystem Input Constraints Solar radiation Global carbon cycle Rate of nutrient cycling Rate of hydrological cycle Input? System Output 5/26/2011 2nd Viennese Talks on Resilience Research & Networks

11 Ecosystem Output Constraints Rate of decomposition Rate of accumulation of unwanted byproducts Finding others to take your waste Input Output? System 5/26/2011 2nd Viennese Talks on Resilience Research & Networks

12 Input Environment Ecosystem? Output Ecosystems have evolved and developed within these input-output environmental constraints. What patterns of organization and complexity arise in ecosystems?

13 Measuring the state of the system/ dynamic trajectory Increase in complexity and order as the result of controlled growth. HOW CAN WE MEASURE THIS COMPLEXITY?

14 Some attempts to measure ecological complexity using weighted quantities Emergy E i i Eco Exergy c i i Ascendency TST T T ij.. log T T ij T T i.... j

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17 Adaptive cycle: Holling s four-stage model of ecosystem dynamics: growth, conservation, disturbance, and reorganization

18 Conservation mature stage Exergy stored Reorganization Release creative destruction Exploitation pioneer stage Connectedness Ecosystem succession in the collapse dynamic

19 Benefits of collapse Schumpeter labeled the collapse, creative destruction, since it allowed for new configurations and innovation opportunities

20 Developmental potential Connectedness Developmental opportunities result from the collapse

21 Do all properties follow this lazyeight pattern? Hypothesis about ecosystem properties: Burkhard, Fath, Muller. EcoMod in press. Energetic properties Network properties System properties

22 Energetic property physical exergy storage number of connections

23 Energetic property eco-exergy storage number of connections

24 Energetic property exergy capture (GPP) LAI number of connections 5/26/2011 2nd Viennese Talks on Resilience Research & Networks

25 Energetic property 3 emergy number of connections

26 Energetic property total entropy production (CO 2 ) number of connections

27 2 Network property 3 ascendancy 4 1 number of connections

28 Network property indirect effects, cycling number of connections

29 Network property synergism, mutualism number of connections

30 System property 2 3 adaptability 4 1 number of connections

31 System property 3 vulnerability number of connections

32 System property 4 1 resilience 2 3 number of connections

33 CONCLUSIONS Ecological systems go through an adaptive cycle of growth, stability, collapse and reorganization. Some metrics track this dynamic. We rely on a greater allocation of energy to maintain the complex structures created. With increasing connectedness, risks of brittleness grow: resilience decreases. Resilience depends on the system redundancy and organization.

34 The Dismal Theorem: If the only ultimate check on the growth of population is misery, then the population will grow until it is miserable enough to stop its growth. The Utterly Dismal Theorem: Any technical improvement can only relieve misery for a while, for so long as misery is the only check on population, the improvement will enable population to grow, and will soon enable more people to live in misery than before. The final result of improvements, therefore, is to increase the equilibrium population which is to increase the total sum of human misery. The moderately cheerful form of the Dismal Theorem: If something else, other then misery and starvation, can be found which will keep a prosperous population in check, the population does not have to grow until it is miserable and starves, and it can be stably prosperous. 5/26/2011 2nd Viennese Talks on Resilience Research & Networks K. Boulding, 1971.

35 Thank you for your Attention!

36 Cycles and the collapse dynamic What evidence is there of cycles in society and economy? What does it mean that there are declining marginal benefits to complexity as a problem solving tool? Is prolonging the collapse only making it longer to fall? Can we find benefits of collapse? Examples from the current financial crises. What about Kondratiev cycles? 5/26/2011 2nd Viennese Talks on Resilience Research & Networks