Table 2 Parameters estimation and significance of the aboveground biomass model with forest management type as categorical variable before harvest (age < 100 years) and with harvest (all data)
From: Effects of forest management on biomass stocks in Romanian beech forests
Parameters | Estimate | std error | t value | Pr(>|t|) |
|---|---|---|---|---|
Before harvest: age < 100 years | ||||
N = 1863, RMSE = 97.08, R2 = 0.46 | ||||
Intercept (Production) | −71.056 | 8.864 | − 8.016 | 1.91e–15 |
Protected | −9.75 | 23.725 | − 0.411 | 0.681 |
Protection | 5.528 | 6.787 | 0.814 | 0.415 |
Age | 0.471 | 0.118 | 3.993 | 6.79e–05 |
Dominant height | 1.249 | 0.041 | 30.496 | < 2e–16 |
With harvest: no age filter | ||||
N = 2703, RMSE = 113.30, R2 = 0.43 | ||||
Intercept (Production) | −76.142 | 8.311 | −9.161 | < 2e–16 |
Protected | 15.438 | 19.839 | 0.778 | 0.437 |
Protection | 16.943 | 6.050 | 2.800 | 0.005 |
Age | 0.257 | 0.074 | 3.472 | 5.25e–05 |
Dominant height | 1.323 | 0.036 | 36.764 | < 2e–16 |