Table 3.
Pure contributions of individual predictors and of the full set of predictors (full model) for the 12 studied tree species, derived from variable GLMs with cover abundance of mature trees as the response variable and environmental predictors based on data from 1,075 study plots across Switzerland. Numbers indicate the deviance explained by the individual predictors (adj.D 2 multiplied by 100) and by the full model (adj.D 2). The direction of the trend (T) between the predictor and the response variable is indicated as positive linear “+,” negative linear “−,” positive unimodal “+/−,” or with no clear trend “N.” “Optimum” (Opt.) for DD, RH, AT/PT, and C/N specifies the environmental conditions for which maximal abundance was predicted if the trend was positive unimodal. Boldface indicates adj.D 2 ≥ 1.5% for individual predictors. For p‐values, see (p). Abbreviations and units of predictors are explained in Table 2. Note that the sum of the pure contributions of the individual predictors differs from the deviance explained by the full model due to joint contributions
| Species | Full model | ||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Climate | Soil | ||||||||||||||||||||||||||||
| Temperature | Water | Nutrients | Soil aeration | Full model | |||||||||||||||||||||||||
| DD | T | Opt. °C | p | T‐Cont | T | p | RR | T | p | RH | T | Opt. % | p | AT/PT | T | Opt. | p | C/N | T | Opt. | p | BS | T | p | W‐Level | T | p | ||
| P. abies | 5.70 | +/− | 1100 | .00 | 0.10 | − | .64 | −0.10 | + | .95 | 0.00 | + | .76 | 1.60 | + | .02 | 1.70 | +/− | 27 | .02 | 0.50 | − | .26 | 0.40 | − | .32 | 0.28 | ||
| A. alba | 5.50 | +/− | 1500 | .00 | 0.00 | +/− | .86 | 0.40 | + | .40 | 3.30 | +/− | 76 | .00 | 0.70 | + | .28 | 0.60 | +/− | 18 | .34 | 0.60 | − | .31 | 0.60 | +/− | .29 | 0.30 | |
| P. sylvestris | 2.60 | +/− | 1900 | .06 | 0.60 | + | .47 | −0.10 | N | .95 | 1.20 | − | .28 | 0.50 | +/− | 0.65 | .53 | 9.50 | + | .00 | 2.60 | + | .07 | 0.50 | + | .54 | 0.45 | ||
| F. sylvatica | 10.10 | +/− | 1900 | .00 | 1.20 | +/− | .01 | 0.30 | + | .29 | 0.30 | +/− | 73 | .27 | 1.90 | +/− | 0.90 | .00 | 1.40 | +/− | 15 | .01 | 0.50 | N | .12 | 3.30 | + | .00 | 0.37 |
| F. excelsior | 2.60 | + | .09 | 0.20 | +/− | .77 | 0.00 | − | .90 | 0.40 | − | .62 | 0.70 | − | .48 | 8.00 | − | .00 | 2.80 | + | .07 | 1.10 | − | .33 | 0.55 | ||||
| A. ps.platanus | −0.10 | N | .97 | −0.10 | − | .98 | 0.20 | + | .73 | 1.60 | +/− | 75 | .24 | 0.20 | + | .74 | 7.30 | − | .00 | 2.50 | + | .11 | 1.10 | N | .36 | 0.29 | |||
| U. glabra | 4.80 | + | .35 | 3.20 | N | .49 | 0.20 | + | .94 | 2.10 | +/− | 74 | .63 | 4.30 | + | .39 | 1.50 | − | .71 | 7.20 | + | .21 | 3.50 | N | .46 | 0.39 | |||
| P. avium | 4.00 | + | .66 | 1.40 | + | .86 | 0.70 | N | .92 | 1.60 | − | .84 | 0.80 | − | .92 | 2.90 | − | .74 | 0.70 | N | .92 | 1.40 | N | .86 | 0.39 | ||||
| Q. robur | 8.50 | + | .04 | 0.80 | +/− | .71 | 1.00 | N | .66 | 0.60 | − | .78 | 1.90 | +/− | 0.80 | .47 | 0.60 | − | .78 | 0.70 | N | .73 | 0.20 | N | .90 | 0.40 | |||
| Q. petraea | 1.90 | + | .35 | 0.10 | + | .88 | 1.00 | N | .57 | 1.90 | +/− | 68 | .34 | 4.00 | +/− | 0.70 | .12 | 1.50 | +/− | 19 | .42 | 0.40 | N | .75 | 0.50 | + | .72 | 0.30 | |
| Q. pubescens | 0.60 | + | .72 | 1.20 | + | .52 | 1.40 | N | .49 | 2.50 | − | .27 | 9.70 | +/− | 0.60 | .01 | 2.50 | +/− | 18 | .28 | 0.20 | + | .87 | 0.20 | + | .89 | 0.59 | ||
| C. betulus | 3.20 | + | .36 | 0.20 | +/− | .92 | 4.50 | N | .24 | 0.90 | − | .72 | 2.20 | +/− | 0.80 | .49 | 2.20 | − | .48 | 0.10 | N | .92 | 0.40 | N | .86 | 0.40 | |||