Data and Methods
Bioclimate envelope models were previously developed for P. menziesii and P. contorta. Sources of these models are identified below in Table 1, and climatic variables used for each respective model are identified below in Table 2. As outlined in Table 2, eight climate variables were used in developing the Douglas Fir bioclimate model, and nine climate variables were used in developing the Lodgepole pine bioclimate model. Of these variables, only four variables are consistent between the two.
These previous studies have also compiled provenance growth results for P. menziesii and P. contorta. Data sources used for this study are also identified below in Table 1. Using age and heights in these studies, a model was created for height growth of each species across Europe (Figure 2a and 2b). Heights were used as a measure of relative growth since it was consistently measured across provenance trials, and is not as susceptible as spacing and competition as factors such as diameter. The height growth model is used to normalize the relative growth of different ages of each species for comparison. The model was developed using Xuru's Website (n.d.) with a two parameter setting. The model was selected based on the best fit following a curve shape that may be reflected in nature. The difference between actual height of the provenance trial used to determine the relative species growth success against the probability of presence (or habitat suitability) in previously developed bioclimate envelope models. Environmental factors such as mean annual temperature and mean annual precipitation from ClimateEU were noted relative to height growth. Table 1: data sources used
Table 2: Climatic variables used in Bioclimate Envelope Model creation
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Figure 2a: developed model for P. menziesii height growth
Figure 2b: developed model for P. contorta height growth
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(Draft website developed only for the purposes of Ren R 711 final project.)