Preliminary results
On development of the model, general trends could be observed between countries for both Douglas fir and Lodgepole pine (Figure 3). Finland, in general, had slower height growth in Europe, whereas Croatia and the UK and Ireland had faster tree growth than anticipated. Germany, Sweden, and France generally followed the developed height growth model.
Appendix figure 1: Selected countries relative to the height model.
As tests are plotted ranging from north to south (Figure 4a and 4b), an overall increasing trend is observed as northern latitdues decrease from Finland to Croatia in both Douglas fir as well as Lodgepole pine provenance trials. This increasing trend ends south of Croatia for Douglas fir where height growth suddenly decreases. There were no provenance tests for Lodgepole pine south of Croatia to determine if this trend is consistent across species.
Additional trends to note can be seen in Figures 4c and 4d below. Areas such as Norway supported the growth of Douglas fir trees, even though the bioclimate model predicted no probability of presence although growth of these trees in such an area were slower relative to the rest of Europe. For Douglas fir, an interesting trend to note was in Netherlands, where growth was higher than our height model predicted even though the suitability of the area was less than 5%.
Figure 4: General trends in height growth relative to the height growth model and bioclimate suitability for Douglas Fir and Lodgepole pine. Residuals plotted from north to south are illustrated in (a) and (b); individual residuals relative to their bioclimate suitability are illustrated in (d) and (e). Douglas fir provenance trials and bioclimate envelope model obtained from Isaac-Renton et al (2014). Lodgepole pine provenance trials and bioclimate model obtained from Herva, M (2015).
(Draft website developed only for the purposes of Ren R 711 final project.)