On the Ecology of Mountainous Forests in a Changing Climate: A ...

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Table of contents
A BSTRACT..........................................................................................vi
KURZFASSUNG ..................................................................................viii
1. INTRODUCTION................................................................................ 1
1.1 Climatic change and mountainous forests ............................................ 1
1.2 Methods for the analysis of forest ecosystems....................................... 3
1.3 Spatial scales in forests and corresponding models ................................. 4
1.4 Forest gap models....................................................................... 7
1.5 Objectives of this study................................................................11
2. ANALYSIS OF EXISTING FOREST GAP MODELS ..........................................13
2.1 Model formalism.......................................................................13
2.2 Statistical analysis ......................................................................17
2.2.1 Characteristics of model behaviour on a single forest patch .............17
2.2.2 Statistical sampling of the stochastic process ..............................23
2.3 Structural sensitivity...................................................................27
2.3.1 Sensitivity to structural simplifications .....................................27
2.3.2 Sensitivity to the formulation of climatic influences ......................36
2.4 Summary & conclusion ..............................................................42
3. THE FOREST MODEL FORCLIM ............................................................44
3.1 Structure of FORCLIM .................................................................44
3.2 Model assumptions.....................................................................45
3.2.1 Plant submodel: Tree population dynamics ................................45
3.2.2 Soil submodel: Turnover of soil organic matter ...........................51
3.2.3 Environment submodel: The abiotic forest environment .................54
3.3 Model equations........................................................................57
3.3.1 FORCLIM-P: A forest gap model of tree population dynamics ..........57
3.3.2 FORCLIM-S: A model of the turnover of soil organic matter ............73
3.3.3 FORCLIM-E: A model of the abiotic environment.........................77
3.4 Parameter estimation ...................................................................83
3.4.1 FORCLIM-P....................................................................83
3.4.2 FORCLIM-S....................................................................86
3.4.3 FORCLIM-E....................................................................87
3.5 Model implementation.................................................................88
3.5.1 Modelling and simulation tools..............................................88
3.5.2 Coupling the submodels......................................................89
3.5.3 The concepts of sites and species........................................92
3.5.4 Other implementational aspects..............................................92
4. BEHAVIOUR OF FORCLIM ALONG A TRANSECT IN THE EUROPEAN ALPS...........94
4.1 FORCLIM-E.............................................................................94
4.2 FORCLIM-S.............................................................................99