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Table I
Description of belowground and aboveground dependent and independent variables determined for each of the 29 plots.
| Variable | Units | Additional remarks |
|---|---|---|
| Belowground dependent | ||
| Armillaria soil weight | g m −3 | Mean fresh weight of Armillaria rhizomorphs of 4 soil samples |
| Armillaria soil length | cm m−3 | Mean length of Armillaria rhizomorphs of 4 soil samples |
| Armillaria soil frequency | % | Percentage of soil samples with Armillaria rhizomorph presence |
| Aboveground dependent | ||
| Armillaria stump colonisation | % | Percentage of stumps with Armillaria signs |
| Armillaria dead tree colonisation | % | Percentage of dead trees with Armillaria signs |
| Independent | ||
| Elevation | m | Meters above sea level |
| Slope | % | Slope percentage, measured with inclinometer |
| North exposure | ° | 0° implies north, > 0 and < 0 values, east and west exposure respectively |
| Soil depth | cm | One unique observation in the centre of each plot |
| Shrub cover | 0–4 | Thresholds of 25% shrub coverage; 0, no shrub coverage |
| Herbaceous cover | 0–4 | Thresholds of 25% herbaceous coverage; 0, no herbaceous coverage |
| Moss cover | 0–4 | Thresholds of 25% moss coverage; 0, no moss coverage |
| Light index | No units | Mean of light indexes of the main understory plant species (Ellenberg et al., 1991) |
| Moisture index | No units | Mean of soil-moisture indexes of the main understory plant species (Ellenberg et al., 1991) |
| Nitrogen index | No units | Mean of nitrogen-presence indexes of the main understory plant species (Ellenberg et al., 1991). |
| pH | No units | Mean pH of 4 soil sub-samples per plot (Oliva and Colinas, 2007) |
| LAI | m2 m−2 | Leaf area index, using hemispherical photos and analysed with Gap Light |
| Analyzer software 2.0 (Oliva and Colinas, 2007) | ||
| Dominant height | m | Mean height of the 100 largest- diameter trees per hectare |
| Mean height | m | Mean height of all A. alba trees within a plot |
| Density | stems ha−1 | A. alba density |
| Canopy closure | % | Mean crown closure of all A. alba trees in plot. Crown closure calculated as the |
| number of horizontal crown quadrants touching/overlapping other trees | ||
| Hart-Becking index | m | Hart-Becking index for A. alba trees. Assuming triangular tree distribution |
| Slenderness | m m−1 | Mean ratio, between height and diameter at breast height (DBH), of all trees in plot |
| BA | m2 ha−1 | Basal area. Accompanying species also included |
| Mean DBH | cm | Diameter of the mean BA tree |
| Type of mixture | class | Includes four classes: A. alba-F. sylvatica mixed stands, A. alba-P. sylvestris mixed |
| stands, A. alba-P. uncinata mixed stands and pure A. alba stands | ||
| Silver fir dynamics index | No units | Indicator of A. alba increase relative to co-existing tree species (Oliva and Colinas, |
| 2007). Values higher than 1 imply fir decrease, values lower than 1 imply increasing | ||
| fir composition | ||
| Harvested BA | No units | Ratio between BA of stumps and BA of living trees |
| Number of interventions | No units | Visually assessed by the decay of stumps |
| Thinning intensity of the | m2 ha−1 | Calculated as the total harvested BA divided by the number of interventions |
| average intervention | ||
| Other sp. BA | % | Percentage of BA occupied by other species |
| Silver fir defoliation | % | Percentage of A. alba trees showing defoliation |
| Silver fir chlorosis | % | Percentage of A. alba trees showing chlorosis |
| Other species defoliation | % | Percentage of damaged trees of accompanying species according to their defoliation |
| Percentage weighted by the basal area of each tree | ||
| Silver fir mortality | No units | Ratio between BA of dead firs and BA of living firs |
| Other species mortality | No units | Ratio between BA of dead trees of accompanying species and BA of living trees |
| Mortality | No units | Ratio between BA of dead trees and BA of living trees |