distributions of c 3 and c 4 plants travis wicks
TRANSCRIPT
C3-C4 ExamplesC4C3
Kaupag.com
Warm-season grasses
Scientificamerican.comTreesdirect.co.uk
Most plants
En.wikipedia.org
Influences on Distribution
• Temperature
• CO2 concentration
• Precipitation patterns
• Light intensity
Goals
Compare with:– Koch et al. (2004)– Still and Powell
(2010)
Fraction C4
0 - 0.05
0.05 - 0.2
0.2 - 0.3
0.3 - 0.4
0.4 - 0.5
0.5 - 0.6
0.6 - 0.7
0.7 - 0.8
0.8 - 1
ÜModern C4 Distribution
ModelsKoch et al. (2004)
– Based on regressions on modern distributions– Purely climate-based– Inputs:
• mean annual temperature• mean annual precipitation• mean summer precipitation
Models
Still and Powell (2010)– Climate aspect based on experimental data– MODIS and Global Land Cover (GLC) vegetation
data included• Eliminates problem of plant physiology distributions
– Inputs:• Mean monthly precipitation• Mean monthly temperature• MODIS % herbaceous layer• Global Land Cover Map 2000
Conclusions
• Both models have their respective problems– Hybridize the two
• Other possible factors:– Fire regime– Herbivores
• Are the systems truly in equilibrium?– Natural variability