Dynamik der Biosphäre. Exogene Dynamik, Biosphärenmodelle

Transcription

1 Dynamik der Biosphäre Exogene Dynamik, Biosphärenmodelle Wintersemester 2004/2005 Wolfgang Cramer Lehrstuhl "Globale Ökologie" -> "Teaching"

2 Heute... Modellierung der Biosphäre (Formlose) Zwischenevaluierung

3 Lebensformen

4 Pflanzentypen

5 Kontrollvariablen (Box) max mean temperature of the warmest month ( o C) min mean temperature of the coldest month ( o C) T range between T min and T max ( o C) I max min mean total annual precipitation (mm) moisture index, defined as the ratio between P and annual potential evapotranspiration (Thornthwaite and Mather 1957) mean total precipitation of the wettest month (mm) mean total precipitation of the driest month (mm) Tmax mean total precipitation of the warmest month (mm)

6 Mechanismen im BIOME-Modell tolerance / requirement ecophysiological mechanism bioclimatic index climatic variable (monthly means) cold tolerance killing temperature during coldest period of the year Tmin (temperature of the coldest month, lower limit) temperature chilling requirement winter chilling period required for budburst of woody plants Tmin (temperature of the coldest month, upper limit) temperature heat requirement annual growth respiration requirement GDD (growing degree days above 0 o C and 5 o C) temperature moisture requirement / drought tolerance soil moisture availability AET/PET (annual actual evapotranspiration / annual potential evapotranspiration) temperature precipitation cloudiness

7 T min GDD 0 GDD 5 T max AET/PET plant functional type min max min min min min max es tropical evergreen tropical raingreen warm-temperate evergreen temperate summergreen cool-temperate conifer boreal evergreen conifer boreal summergreen n-trees sclerophyll/succulent warm grass/shrub cool grass/shrub cold grass/shrub hot desert shrub 22.0 cold desert shrub 100 plants (dummy type)

8 BIOME 1

9 BIOME 1

10 Olson et al.

11 Olson et al.

12 The Holdridge system

13 Interacting Scales in Biogeochemistry Biosphere Ecosystems Plants carbon allocation and growth global biogeochemistry disturbance and succession storms, fire evolution geographical distribution of vegetation type plant seasonality Leaves Cells plant metabolism water- and nutrient budget competition for resources and ecological strategies Molecules photosynthesis Seconds Minutes Hours Years Decades Centuries

14 Latitude, climate, soil texture, CO 2 Next year insolation, daylength, potential evapotranspiration snowmelt and -accumulation soil temperature Soil water Summergreen phenology Photosynthesis Water balance Fraction of PAR intercepted ~ foliar projective cover Raingreen phenology GPP Maintenance respiration Litter and soil C NPP Allocation to C compartments, allometry and growth sapwood-heartwood conversion, leaf and fine root turnover Litter and soil organic matter decomposition Mortality (Fire, Stress, Climate) Establishment PFTs leaf C, fine root C, sapwood C, heartwood C population density, mean crown area, foliar projective cover Sitch et al. Global Change Biology 9 (2003), Daily/monthly time step Plant Physiology Vegetation Dynamics

15 The Lund-Potsdam-Jena Dynamic Generic Vegetation Model (LPJ)

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