Table 1 Main characteristics of the NFI plots selected to estimate the self-thinning relationships (see Section 3)
| No. of plots | Stand density (trees/ha) | Quadratic mean diameter (cm) | Lower diameter threshold | Upper diameter threshold | Mean pureness (%) | No. of removed ecological areas (% of plots removed) | ||||
|---|---|---|---|---|---|---|---|---|---|---|---|
Mean | Min | Max | Mean | Min | Max | ||||||
Pubescent oak | 429 | 630.3 | 39.3 | 1,984.5 | 21.2 | 15.0 | 36.5 | 15.0 | 37.0 | 98.6 | 14 (9.8) |
Pedunculate oak | 1,244 | 481.0 | 39.3 | 2,205.0 | 26.0 | 15.1 | 36.9 | 15.0 | 37.0 | 97.7 | 11 (2.2) |
Sessile oak | 1,110 | 649.5 | 39.3 | 2,544.5 | 23.0 | 15.0 | 30.0 | 15.0 | 30.0 | 97.5 | 19 (3.7) |
Common beech | 2,409 | 589.4 | 14.1 | 2,710.3 | 27.3 | 16.0 | 40.0 | 16.0 | 40.0 | 98.1 | 18 (2.2) |
Scots pine | 3,995 | 782.4 | 39.3 | 3,301.0 | 22.2 | 15.0 | 33.0 | 15.0 | 33.0 | 98.7 | 19 (2.7) |
Aleppo pine | 698 | 499.7 | 28.3 | 2,672.2 | 23.5 | 15.0 | 40.0 | 15.0 | 40.0 | 99.3 | 5 (2.2) |
Corsican pine | 357 | 566.5 | 67.6 | 1,945.2 | 30.5 | 18.0 | 49.8 | 18.0 | 50.0 | 98.7 | 31 (20.7) |
Maritime pine | 5,153 | 524.4 | 39.3 | 3,517.1 | 26.3 | 16.0 | 37.0 | 16.0 | 37.0 | 99.3 | 10 (0.7) |
Norway spruce | 1,301 | 756.1 | 42.4 | 3,652.3 | 29.2 | 15.0 | 45.0 | 15.0 | 40.0 | 97.9 | 17 (3.2) |
Silver fir | 1,778 | 653.3 | 70.7 | 2,908.0 | 29.6 | 15.0 | 44.9 | 15.0 | 45.0 | 97.5 | 10 (1.0) |
Douglas fir | 957 | 632.8 | 28.3 | 2,661.2 | 28.1 | 20.0 | 49.6 | 20.0 | 50.0 | 99.1 | 11 (4.2) |