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

Parameter sensitivity & model validation 137
FORECE
Quercus petraea
FORECE
ForClim
T (°C)
P (mm/yr)
FORC LIM-E/P
FORC LIM-E/P/S
T (°C)
T (°C)
P (mm/yr)
P (mm/yr)
Fig. 5.7: Contour plot of Quercus petraea biomass [t/ha] as simulated by FORECE (top),
FORCLIM-E/P (bottom left), and FORCLIM-E/P/S (bottom right).
remains the most abundant species. In FORCLIM, Quercus spp. (Fig. 5.7) is present as
well, but it does not attain the abundance hypothesized by Rehder and Ellenberg.
The FORCLIM-S submodel is especially important for simulating Quercus spp. (cf.
Fig. 5.7 with Q. petraea as an example). While FORECE fails to simulate the presence of
oak as long as F. silvatica is present, the FORCLIM-E/P model generally predicts the occurrence
of Q. petraea in the right places (Fig. 5.1), but the species extends too far into
the area around T l = 5 °C and P l = 700 mm (Fig. 5.7). The E/P/S model may exaggerate
the importance of Q. petraea at temperatures below 10 °C, where oaks attain more
than 10% of the total aboveground biomass. Moreover, in FORCLIM-E/P/S Q. petraea
may extend too far towards low temperatures (down to T l ≈ 5 °C).