Table 2.
Comparison of pre-1880 and post-1880-forests according to different attributes deduced from forest inventory data (NFI) for the Swiss Alps. Data pertain to observations in the observation period NFI4 4 (2009–2013).
| Attributes | Pre-1880 forests Average value (Stdv.) |
Post 1880 forests Average value (Stdv.) |
p-values Wilcoxon rank-sum test |
| Total current wood volume Dead wood volume |
420.9 m3/ha (270) 31.3 m3/ha (57) |
343.8 m3/ha (274) 27.3 m3/ha (56.2) |
<0.001 0.02 |
| Attributes | Pre-1880 forests Number of counts |
Post 1880 forests Number of counts |
p-values Chi-squared |
| Total number of plots | 1114 | 856 | |
| Young growth (<12 cm DBH) | 66 (6%) | 54 (6%) | n.s |
| Pole wood (12–30 cm DBH) | 156 (14%) | 180 (21%) | <0.001 |
| Timber wood 1 (30–50 cm DBH) | 306 (27%) | 202 (21%) | 0.05 |
| Timber wood 2 (>50 cm DBH) | 275 (25% | 125 (15%) | <0.001 |
| Mixed diameter class | 311 (28%) | 295 (34%) | 0.002 |
| Crown closure: closed | 284 (25%) | 202 (24%) | n.s. |
| Crown closure: normal-loose | 331 (30% | 217 (25%) | 0.04 |
| Crown closure: scattered-open | 295 (26%) | 244 (29%) | n.s. |
| Crown closure: spatially aggregated | 120 (11%) | 159 (19%) | <0.001 |
| Crown closure: multilayered dense | 84 (8%) | 34 (4%) | 0.001 |
| Dominant tree species Picea abies | 540 (48%) | 377 (44%) | 0.02 |
| Dominant tree species Abies alba | 147 (13%) | 24 (3%) | <0.001 |
| Dominant tree species Larix decidua | 96 (8%) | 146 (15%) | <0.001 |
| Other coniferous dominant species | 63 (6%) | 43 (3%) | n.s. |
| Dominant tree species Fagus sylvatica | 147 (10%) | 82 (13%) | 0.02 |
| Other broadleaved dominant species | 124 (11%) | 195 (22.8) | <0.001 |
| Signs of grazing | 78 (7%) | 163 (19%) | <0.001 |
| Last management intervention ≤20 years | 616 (55%) | 351 (41%) | <0.001 |
| Last management intervention >50 years | 316 (28%) | 358 (43%) | <0.001 |
Note: n.s.: p-values >0.05.