Table 5 Non-linear models describing relationships between forest stand characteristics (predictors) and biomass conversion and expansion factors (BCEFs) (Mg m−3)
From: Tree and stand level estimations of Abies alba Mill. aboveground biomass
Component | Predictor | Equation | a | SE | b | SE | c | SE | RMSE | R 2 | AIC | AIC0 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Aboveground | Age | 16 | 0.42711 | 0.02002 | 3.23549 | 0.65357 | – | – | < 0.0001 | 0.731 | − 34.350 | − 21.890 |
BA | 16 | 0.35814 | 0.03994 | 4.91087 | 1.25372 | – | – | < 0.0001 | 0.630 | − 30.836 | ||
N | 14 | 0.27545 | 0.06616 | 0.09000 | 0.03464 | – | – | 0.0006 | 0.398 | − 25.479 | ||
D | 16 | 0.42125 | 0.02382 | 1.58348 | 0.36978 | – | – | < 0.0001 | 0.671 | − 32.112 | ||
H g | 16 | 0.42295 | 0.02304 | 1.36205 | 0.31094 | – | – | < 0.0001 | 0.681 | − 32.449 | ||
V | 16 | 0.45594 | 0.01700 | 11.44751 | 2.48881 | – | – | < 0.0001 | 0.702 | − 33.191 | ||
Branches | Age | 16 | 0.02281 | 0.01345 | 2.09071 | 0.43905 | – | – | < 0.0001 | 0.716 | − 43.103 | − 31.261 |
BA | 14 | 10.54166 | 3.64572 | − 1.42971 | 0.11097 | – | – | 0.0015 | 0.928 | − 58.246 | ||
N | 14 | 0.00314 | 0.00378 | 0.44857 | 0.15488 | – | – | 0.0089 | 0.426 | − 35.370 | ||
D | 16 | 0.01756 | 0.01501 | 1.05158 | 0.23307 | – | – | < 0.0001 | 0.693 | − 42.267 | ||
H g | 16 | 0.01577 | 0.01241 | 0.95407 | 0.16746 | – | – | < 0.0001 | 0.783 | − 46.063 | ||
V | 16 | 0.03667 | 0.00579 | 8.55722 | 0.84732 | – | – | < 0.0001 | 0.919 | − 56.896 | ||
Foliage | Age | 14 | 4.04670 | 1.44364 | − 1.11395 | 0.12012 | – | – | 0.0070 | 0.919 | − 51.740 | − 26.114 |
BA | 14 | 27.78346 | 19.40171 | − 1.74710 | 0.23352 | – | – | 0.0039 | 0.835 | − 43.948 | ||
N | 14 | 0.00027 | 0.00034 | 0.76792 | 0.15236 | – | – | 0.0115 | 0.803 | − 42.004 | ||
D | 17 | 0.02525 | 0.01045 | 6.27813 | 4.30854 | 1.81029 | 0.37889 | < 0.0001 | 0.960 | − 57.554 | ||
H g | 14 | 1.66513 | 0.21970 | − 1.15334 | 0.06266 | – | – | 0.0004 | 0.975 | − 64.697 | ||
V | 14 | 4.46600 | 0.91985 | − 0.74732 | 0.04530 | – | – | 0.0038 | 0.965 | − 60.987 | ||
Stem | Age | 16 | 0.39774 | 0.01469 | − 1.51562 | 0.47955 | – | – | < 0.0001 | 0.526 | − 41.162 | − 34.949 |
BA | 16 | 0.43163 | 0.02630 | − 2.35413 | 0.82543 | – | – | < 0.0001 | 0.475 | − 40.031 | ||
N | 14 | 0.61201 | 0.10709 | − 0.07956 | 0.02674 | – | – | < 0.0001 | 0.513 | − 40.859 | ||
D | 16 | 0.40500 | 0.01445 | − 0.82925 | 0.22430 | – | – | < 0.0001 | 0.603 | − 43.110 | ||
H g | 14 | 0.20618 | 0.03018 | 0.18514 | 0.04654 | – | – | < 0.0001 | 0.673 | − 45.231 | ||
V | 14 | 0.15208 | 0.03364 | 0.14652 | 0.03664 | – | – | < 0.0001 | 0.687 | − 45.716 |