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Ecosystem Theory Course2.1.1: Basics of Ecosystem Analysis May 24, 2006 Ecosystem ProtectionConcepts A Ecosystem ProtectionII. à W. Windhorst -Ecosystem Integrity, theConcept à Pres. Timo -Ecosystem Integrity, Applications à Pres. Timo TheUNCBD Ecosystem Approach –CaseStudies à W. Windhorst -ForestEcosystems à Pres. Pawel Ecosystem Theory. à F. Müller B OrganizingSalzau -NetworkTheory à Pres. Kamil Web pages -Thermodynamics à Pres. Aiko Transfer -HierarchyTheory à Pres. Pawel Workingplans -Gradient Principles à Pres. Lech Problems August Macke: Felsige Landschaft, 1914, Aquarell, 24 ×20 cm, Land: Deutschland, Stil: Expressionismus. What are theories? Popper: Abstract "Theory is the fishing net description, that scientists cast explanation and to catch the world, organization to explain it of a scientific and to control it." disciplin. Theories are - sets of hypotheses empirically or deductively - non-evaluative based, aggregating and - capable of being integrating falsified representations - prognostic of the proved - applicable to knowledge of a single cases scientific disciplin. - directing the development, What orientation, and are Theories structure of the disciplin theories? Which theories are relevant for ecosystem compre- hension? Approaches: Farina: - Hierarchy Theory "Theories are interpreting - Fractal Geometry the complexity and - Chaos Theory heterogeneity of the - Catastrophe environment (landscape)" Theory - Self-Organization Naveh & Liebermann: - Information Theory "The organization of - Thermodynamics complexity in landscape - Theory of Which structure and function Dissipative theories has become a central Structures issue in contemporary - Percolation Theory are landscape ecology." - Metapopulation relevant Theory for - Systems Source- ecosystem Landscape Sink - Spatial Pattern compre- Theories Analysis hension? Cybernetics Network Theory Regulation and Control Flow Analysis in in Complex Systems, Complex, Interacting Feedback Loops, Systems Homoeostasis, e.g. Electrical Circuits Optimization Ecological Modelling Trophic Stability Theory Flows, Which Conceptual Landscape Chains, and Networks theories and Ecosystem Models Food Webs Indirect Effects are relevant for ecosystem Ecosystem compre- hension? Theories Information Theory Hierarchy Theory Improbability of the Analysis of Subsystems Occurence of an Event with Asymmetric Inter- actions Syntactic, Semantic, Scales, Holons, Pragmatic Information Constraints and Filters Measures of Diversity Principles and Methods Measures of Complexity of Scale Distinction Which Ascendency theories - Total Throughflow Fundamentals for the are - Flow Articulation Existence of Emergence relevant for ecosystem A = I * T compre- Ecosystem hension? Theories HolonLevel (+1) SpatialExtent: High Frequencies: Low MinorInteractions Multiple Interactions HolonLevel (0) Filter Constraints Holon Level SpatialExtent: Small (-1) Frequencies: High Hierarchiesand theproblemsof scale Synergetics Thermodynamics Detecting the Principles Analyzing Balances and of Self-Organization in Transfers of Energy Physical, Chemical, and Corresponding Biological and Human Principles Systems Self-Organization Energetic Principles of Ecosystems and of Ecological Landscapes, Self-Organization Gradients and Dissipative Structures Which Emergent Exergy, Entropy, Properties Emergy theories are Orientors relevant Principles of Undisturbed for Ecosystem Development of ecosystem Ecosystems and Theories Landscapes compre- hension? (Voluntary) Homework: Find examplesfor… terrestrial aquatic -circadianerhythms o o -lunearperiodics o o -tideperiodics o o -seasonalrhythms o o -longtermrhythms o o (modifiedafter Holling1995; Hollingetal.2000) AVAILABLE NUTRIENTS Decomposition EXE K-strategy climax R G Y C ON pest S fire U M storm P toanother TION attractor r-strategy pioneer Lotsof dead biomass opportunist Storedexergy Holling’s conceptual model incorporates both Clementsian linear succession and Gleasonian independent, species-level disordered behaviour, which are integrated into a complexity based framework with insights gleaned from catastrophe theory, chaos theory and self-organization theory. FigurefromG. Zurlini Whatisa succession? .... an orderedprocessof communitydevelopment includingregularchangesof thespeciescompositions .... changesoccuringdueto variationsof thespeciesinteractions .... changesoccuringdueto internalprocesseswithinthe community .... changesin communitystructureeffectingchangesin the physicalecosystemfunctions -energy -whichdirection? -water -whichdirection? -nutrients -whichdirection? Typesof successions: -autogeneoussuccessions ---> consequencesof internalprocesses -allogeneoussuccession ---> consequencesof externalinfluences -primarysuccession ---> „natural“development -secondarysuccession ---> followingprimarysuccessionswhichhave developedunderman‘s disturbing influences Typesof successions: -progressive successions ---> complexification -retrogressivesuccession ---> consequencesof disturbances simplification Climax: -final and „stable“communityof a developmentalsequence -climaticalclimax theoreticalcommunitywhichisthetypicalresult of successionswithina certain(climatic) area -edaphicclimax resultof succession, effectingmodificationsof the climaticclimaxcommunitydueto physical modificationsof thesites Threeexamples forecosystem development fromODUM a. Microorganisms in a haysolution Aus: H.J. Müller (1984) Threeexamples forecosystem development fromODUM a. Microorganisms in a haysolution b. Plant successions afterfireand in dune systems Aus: H.J. Müller (1984) Threeexamples forecosystem development fromODUM a. Microorganisms in a haysolution b. Plant successions afterfireand in dune systems c. Primaryproduction and respiration throughout successions Aus: H.J. Müller (1984) A mutualhypothesis fromWeber et al. (1989) A mutual hypothesisof ecosystemdevelopment in phasesof biologicalprocessdominance Import + Autocatalytic system + Internal New Flows, element Cycles Export Integration of new elements (species) into an autocatalytic system will take place, if loss is decreased, internal cycling is optimized, and dampening capacity increases (Weber et al. 1989) Efficiency of the whole as a parameter of selection weber.pre Maximum Size due to the Constraints, Provided by the Site Conditions "Resulting State" "Goal" "Attractor" Time / Maturity / Stage of Development Maximum Size due to the Constraints, Provided by the Site Conditions Dynamics of a potential higher hierarchical level Dynamics of a potential lower hierarchical level Time / Maturity / Stage of Development Ecophysiological and functional orientors System System -lossreduction dynamical organizational -storages -biomass orientors orientors -biomass/production ratio -buffercapacity? -complexity -harvest/throughput -stability? -hierarchicallevels ratio -(meat)stabilty? -semiautonomy -transpiration -resilience? -feedbackcontrol -respiration -resistance? -holistic -respiration/biomass -signalfiltering? determination ratio -criticallity -resourceutilization -connectedness -utility -overconnectedness -intraorganismic -redundancy storages -metabolicquotients Do ecosystemsalwaysfollowtheorientors? Do ecosystemsalwaysfollowtheorientors? No. e) 4 2 g Renewal Conservation a or - Accessible Carbon, - k-Strategy t S - Nutrients and Energy - Climax ( l - Consolidation a t i p a C (Miineralisation) (Adult Stage) RADIPLY SLOWLY d e schnell or t S 1 Exploitation Creative 3 - r-Strategy Destruction - Pioneers - Fire - Opportunists - Storm - Pest - Senescence (Juvenile Stage) ( Disturbance Incorporation) Organization 4box1.pre Connectedness Catalogueof questions •Whatisa successionand howcanwedistinguishsuccessiontypes? •Find examplesforprogressive and retrogresivesuccessions. •Whicharethetypicaldevelopmentalphasesof lakecommunities •on an annualbasis? •within10 years? •within1000 years? •Whatisan orientor? •Whicharethedifferencesbetweentheconceptsof stability, resilience, elasticity, and buffercapacity? •Whicharethecomponentsof the‚adaptive cycle‘referringto •a bacteriapopulation •thedune systemof theislandof Sylt? •theman-environmentalsystemof Schleswig-Holstein duringthepast250 years? StructurizedSystems State withConcentrationGradients StructurizedSystems State withConcentrationGradients Diffusion, Dispersion, Dissipation ThermodynamicEquilibrium (no Gradients) StructurizedSystems State withConcentrationGradients Diffusion, Dispersion, Dissipation ThermodynamicEquilibrium (no Gradients) Dissipative Self-Organisation StructurizedSystems State withNew Gradients Self-Organization: Spontaneous Creation of Macroskopic Structuresfrom Microskopic Disorder Gradient Formation Principlesof Self-Organization: Principlesof Self-Organization: Exergy Import Exergy Degradation EntropyExport Principlesof Self-Organization: Exergy Import ConvertibleEnergy e.g. Radiation CO2-Input Exergy Degradation EnergyTransformation e.g. PhysiologicalProcesses Growth Respiration EntropyExport EnergyOutput e.g. Heat CO2-Output Principlesof Self-Organization: Exergy Import ConvertibleEnergy e.g. Radiation CO2-Input Exergy Degradation EnergyTransformation e.g. PhysiologicalProcesses Growth Respiration EntropyExport EnergyOutput e.g. Heat CO2-Output Gradient Formation Principlesof Self-Organization: Exergy Import Systems State Far fromEquilibrium InternalControl/ Regulation SymmetryBreakingOrganization Exergy Degradation Cooperativityof Subsystems ThermodynamicOpenessof System Constraintsin Hierarchies Meta StabilityafterSmall Impulses EntropyExport Fluctuationsin Phase Transitions Historicityand
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