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Managing for Complexity
Dave Coates, B.C. Forest Service, Smithers, BC
Future Forest Ecosystem Initiative Seminar
May 19, 2009
22
Themes in TalkThemes in Talk Historical focus of silviculture is changing
– societal view of the role and importance of forests– biodiversity and disappearance of primary forest– increased understanding of ecosystem functions and
processes
Silviculture needs – a new conceptual approach on which to base our scientific
understanding of forest ecosystems– to develop a new management framework
Complex systems science and viewing forests as complex adaptive systems can provide silviculture a new conceptual framework
Managing for complexity involves thinking carefully about types of interactive processes that occur within forests and how they enable forests to resist stress and self-organize with minimal intervention after disturbance
33
Acknowledgementsand self-promotion
Island Press 2009
Christian DaveKlaus
Sybille Haeussler, UNBC,helped with many ideas
44
New Realities for SilvicultureNew Realities for Silviculture
An era of new climatesAn era of new climates Changing abiotic conditionsChanging abiotic conditions Invasive speciesInvasive species Unexpected disturbancesUnexpected disturbances Economic and social changeEconomic and social change Generation of novel ecosystemsGeneration of novel ecosystems
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New RealityNew Reality
Climate variability - change in average, variation, and/or extreme values
Fort St. James Summer Min Temperature 1895-2008
-10
-8
-6
-4
-2
0
2
4
6
1895
1900
1905
1910
1915
1920
1925
1930
1935
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1960
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1985
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1995
2000
2005
Year
Tem
per
atu
re (
oC
)
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Morice TSA, combined mean rust incidence by stand and percent of stands with >20% incidence in
1996 (n=66), 1999 (n=98) and 2008 (n=82)
18.6%
7.6% 7.1%
41.5%
7.1%6.2%
0%
5%
10%
15%
20%
25%
30%
35%
40%
45%
1996 1999 2008
Per
cent
Combined Rust Incidence
% stands > 20%
Thanks to Alex Woods
77
Ability to manage will be enhanced/constrained by:– Changing Economic/Social
Conditions
Western Forest Products Stock Quote
2008
New Reality
Minister Bell’scarbon creditsilviculture
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New Reality
Seastedt et al. 2008, Frontiers in Ecology, 547-553
Novel ecosystems will be increasingly common
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Silviculture
Silviculture is the management and study of Silviculture is the management and study of forests to produce desired attributes and forests to produce desired attributes and products. Silviculture has strong traditions products. Silviculture has strong traditions that have been developed, articulated, and that have been developed, articulated, and refined over several centuries – this can be a refined over several centuries – this can be a strength and a limitationstrength and a limitation
Silvicultural practices, regardless of Silvicultural practices, regardless of management objective, aim to control the management objective, aim to control the establishment, composition, structure, growth establishment, composition, structure, growth and and rolerole of trees within managed forests of trees within managed forests
1010
Foundations of Silviculture
Developed from long-term observation, experience, Developed from long-term observation, experience, local trials and researchlocal trials and research
Strong influenced by European silviculture developed Strong influenced by European silviculture developed in 18in 18thth century century
Silvicultural systems are the defining characteristic of Silvicultural systems are the defining characteristic of the disciplinethe discipline
1111
Core Principles of Silvicultural PracticeCore Principles of Silvicultural Practice
Dominant focus on treesDominant focus on trees– often to the exclusion of other plants, animals, and ecosystem processes
Stands as uniform entitiesStands as uniform entities– tree-based stand descriptors averaged over whole area
Agricultural approach to researchAgricultural approach to research– searching for best treatments – emphasis on uniform tree species composition and structure
Scale independent view of practicesScale independent view of practices– linear scaling, variability averaged
Focus on predictabilityFocus on predictability– orderly and predictable forest development– growth and yield models that predict one species– idealized conditions
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New Silvicultural ChallengesNew Silvicultural Challenges Manage forests to provide a variety of desired Manage forests to provide a variety of desired
ecosystem goods and services at an acceptable ecosystem goods and services at an acceptable costcost
Ensure ability of managed forests to adapt to Ensure ability of managed forests to adapt to diverse and unexpected future conditionsdiverse and unexpected future conditions
Prescribe and promote novel ecosystemsPrescribe and promote novel ecosystems
Increase ecosystem resilience and adaptability, and promote desirable outcomes
1313
What is a forest?What is a forest?
1414Dothistroma damaged lodgepole pine plantation
Resilience/Adaptability
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Resilience/Adaptability
MPB damaged lodgepole pine stand
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Silviculture for Resilient and Silviculture for Resilient and Adaptable ForestsAdaptable Forests
Manage forests as complex systemsManage forests as complex systems– requires major shift in philosophical and requires major shift in philosophical and
research approachesresearch approaches– new management toolsnew management tools– new conceptual framework to organize new conceptual framework to organize
thinkingthinking
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AA Complex SystemComplex System
Has many parts (components) The parts interact Interaction among the parts causes the
behaviour of the whole to be more than the sum of its parts.
Traditional Science: reductionist, disciplinary, linearComplex Systems Science: holistic, interdisciplinary(both are quantitative & evidence-based)
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Convergence of Soft & Hard Convergence of Soft & Hard ScienceScience
Hard Science ReductionistQuantitative
PrecisePredictive Models
“Gleasonian” paradigmPrediction, Theory-building
Soft Science Holistic
DescriptiveFuzzy
Conceptual Models
“Clementsian” paradigmClassification
Complex Systems Theory allows these two views to be reconciledComplex Systems Theory allows these two views to be reconciled
1919
What is Complexity?What is Complexity?
Scientific definitions:Scientific definitions: Phenomena that arise due to interactions among Phenomena that arise due to interactions among
the parts of a complex system (emergence and the parts of a complex system (emergence and self-organization)self-organization)
The hidden order that lies between order and The hidden order that lies between order and randomnessrandomness
The amount of information needed to fully The amount of information needed to fully describe or recreate the systemdescribe or recreate the system
2020
Science of Complexity Varied history in multiple disciplines
Set of theoretical frameworks that apply to systems in natural and social sciences
Forest ecosystems are the poster child of complexity because:– they are composed of many parts (trees, insects, soil) and
processes (nutrient cycling, seed dispersion, tree mortality) – the parts and process interact with each other and the
environment over multiple spatial and temporal scales– these interactions can give rise to heterogeneous
structures and nonlinear relationships – these relationships represent a combination of randomness
and order – they contain negative and positive feedbacks – the system is open to outside world– they are sensitive to initial conditions
2121
Google Earth
Much of the order/pattern we see in the world comes, not from top down control, but from local-level (bottom-up) interactions among system components.
(self-organization)
Examples: Examples: ‘hearts & minds’
ant colonies, global recession, viral marketing, civil society
The MOST important The MOST important idea from Complex idea from Complex Systems ScienceSystems Science::
Slide from Sybille Haeussler
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“Complex systems in which the individual components are
constantly reacting to one another, thus continually modifying the
system and allowing it to adapt to altered conditions”
Levin 1998
Complex Adaptive SystemsComplex Adaptive Systems
2323
Forests as Complex Adaptive Systems
Uncertain future conditions– Implies allowing forest development to follow a variety of
possible paths Ill-defined boundaries
– Outside influences inherent characteristic of forest ecosystem dynamics
Never at equilibrium– Adopt view that ecosystem structures and process are
continually changing and this change is important Self-regulated
– Occurs through positive and negative feedback loops– Requires new multi-scale research approaches
Develop unexpected properties– Important factor in ecosystem resilience – ‘creativity”
Affected by initial conditions or previous states – Remember previous states, e.g. coppice systems, present
day structural retention
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Soil
Complex Adaptive Behavior
Plants
Insects
Rain
Light
Negative feed
backP
osit
ive
feed
bac
k
Changing external factors
Initial conditions
Non-linear relationships
Various scales
Em
ergent properties
Disturbances
Complexity: Concept and theory
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Strength and Weaknesses of Strength and Weaknesses of “Old” Silviculture“Old” Silviculture
Dominant focus on treesDominant focus on trees– often to the exclusion of other plants, animals, and ecosystem
processes
Stands as uniform entitiesStands as uniform entities– tree-based stand descriptors averaged over whole area
Agricultural approach to researchAgricultural approach to research– emphasis on uniform composition and structure and best treatments
Scale independent view of practicesScale independent view of practices– linear scaling, variability averaged
Focus on predictabilityFocus on predictability– orderly and predictable forest development– growth and yield models that predict one species– idealized conditions
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Management CriteriaManagement Criteria Traditional Silviculture
– emphasis on control to achieve optimal productivity– presumption of predictability – assessed at stand scale– based on mean response
Silviculture: Managing for Complexity– emphasis on resilience and adaptability– promote flexibility and variability – assessed at systems scale
Focus shifts from predictability & control to exploring alternatives and adapting to uncertainty
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TIME
Ecosyste
m
ch
ara
cte
risti
cs
C
Management objective
A
Resilience managem
ent objective
B
Silvicultural interventions
Modified from Puettmann et al. 2009
Management objective
“Complexity” management approach
2828From Puettmann et al. 2009
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Managing for ComplexityManaging for Complexity
More than a heterogeneous stands
More than an uneven-aged silvicultureMore than diversity
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Differences between:Differences between: Complexity Complexity DiversityDiversity ResilienceResilience
Just because System A is more diverse than Just because System A is more diverse than System B doesn’t necessarily mean System A is System B doesn’t necessarily mean System A is more complex (it’s all about the interactions & more complex (it’s all about the interactions & the feedbacks)the feedbacks)
Complexity doesn’t necessarily give rise to Complexity doesn’t necessarily give rise to resilience (e.g., positive feedbacks can be resilience (e.g., positive feedbacks can be destabilizing; critical dependencies can make a destabilizing; critical dependencies can make a system vulnerable)system vulnerable)
Diversity often (but not always) gives rise to Diversity often (but not always) gives rise to stability or resiliencestability or resilience
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Pine plantationDiverse?
Complex?Resilient?
Order
Mixed species plantationDiverse?
Complex?Resilient?
RandomManaging
for Complexity
Mixed species plantationDiverse?
Complex?Resilient?
3232
Focus on bottom-up approach with elements having direct and indirect influence on system scale
Focus on interactions of subsystems and components
Focus on whole system, rather than components
“Complexity” management approach
3333
Assumption of predictability is replaced by assumption of incomplete knowledge
Decision criteria: flexibility
Higher importance of potential future conditions in decision process
Ensure continued ability of ecosystem to adapt to new conditions
“Complexity” management approach
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Current Species Selection and Current Species Selection and Stocking StandardsStocking Standards
Species choice– strong management focus on one or
two species
Density/stocking– based on stand averages– uniform within and among stands;
desire for sample plots to be similar
3535Pine Plantation - Burns Lake, BC
3636
TIME
Ecosyste
m
ch
ara
cte
risti
cs
C
Management objective
A
Variability in species
and stocking
B
Silvicultural interventions
Modified from Puettmann et al. 2009
Management objective
“Complexity” management approach
