. 2023 Aug 21;18(8):e0289679. doi: 10.1371/journal.pone.0289679

Table 7. Model fits with diameter only.

Response	ΔAIC^*	Equation	Adj. R²	RMSE
Aboveground Biomass, Robinia pseudoacacia	23.2	$A G B = \exp (- 3.9401 + 2.9133 \ln (D))$	0.974	28%
Aboveground Biomass, Betula nigra	28.8	$A G B = \exp (- 4.2841 + 2.6117 \ln (D))$	0.930	52%
Aboveground Biomass, Gliricidia sepium	33.5	$A G B = \exp (- 5.6496 + 3.6019 \ln (D))$	0.950	69%
Aboveground Biomass, Casuarina equisetifolia	24.8	$A G B = \exp (- 2.9969 + 2.2140 \ln (D))$	0.801	61%
Aboveground Biomass, Psidium cattleianum	26.1	$A G B = \exp (- 3.6979 + 2.3974 \ln (D))$	0.745	72%
Aboveground Biomass, Acacia koa	6.2	$A G B = \exp (- 4.3772 + 2.8949 \ln (D))$	0.960	35%
Aboveground Biomass, Morella faya	40.5	$A G B = \exp (- 3.8975 + 3.0206 \ln (D))$	0.935	53%
Aboveground Biomass, Dodonaea viscosa	20.3	$A G B = \exp (- 3.3642 + 2.6119 \ln (D))$	0.960	46%
Aboveground Biomass, N-fixers	98.6^@	$A G B = \exp (- 4.7104 + 3.1323 \ln (D))$	0.907^@	87%
Aboveground Biomass, non-fixers	98.6^@	$A G B = \exp (- 3.8048 + 2.5958 \ln (D))$	0.907^@	87%
Belowground Biomass, Robinia pseudoacacia	25.9	$B G B = \exp (- 4.3616 + 2.6429 \ln (D))$	0.936	42%
Belowground Biomass, Betula nigra	9.2	$B G B = \exp (- 5.1261 + 2.5061 \ln (D))$	0.902	62%
Biomass, Robinia pseudoacacia	23.1	$B = \exp (- 3.4358 + 2.8289 \ln (D))$	0.973	27%
Biomass, Betula nigra	23.8	$B = \exp (- 3.9074 + 2.5752 \ln (D))$	0.927	53%
Foliage, Robinia pseudoacacia	0.0	$F B = \exp (- 5.9554 + 2.8514 \ln (D))$	0.832	70%
Foliage, Betula nigra	2.6	$F B = \exp (- 7.6708 + 3.1084 \ln (D))$	0.757	179%
Foliage, Gliricidia sepium	0.0	$F B = \exp (- 6.5919 + 3.3388 \ln (D))$	0.935	82%
Foliage, Casuarina equisetifolia	3.4	$F B = \exp (- 4.4812 + 2.2615 \ln (D))$	0.761	95%
Foliage, Psidium cattleianum	3.2	$F B = \exp (- 3.5760 + 1.6700 \ln (D))$	0.430	28%
Foliage, Acacia koa	4.5	$F B = \exp (- 4.8276 + 2.4939 \ln (D))$	0.912	51%
Foliage, Morella faya	10.4	$F B = \exp (- 4.4538 + 2.7857 \ln (D))$	0.920	56%
Foliage, Dodonaea viscosa	1.1	$F B = \exp (- 4.2035 + 2.2262 \ln (D))$	0.843	69%
Twigs, Robinia pseudoacacia	9.5	$T w B = \exp (- 5.0187 + 2.5597 \ln (D))$	0.878	62%
Twigs, Betula nigra	2.9	$T w B = \exp (- 4.9089 + 2.3174 \ln (D))$	0.931	45%
Twigs, Gliricidia sepium	2.5	$T w B = \exp (- 8.3394 + 3.6327 \ln (D))$	0.937	90%
Twigs, Casuarina equisetifolia	14.2	$T w B = \exp (- 3.8361 + 1.7959 \ln (D))$	0.696	86%
Twigs, Psidium cattleianum	8.9	$T w B = \exp (- 4.9085 + 2.4936 \ln (D))$	0.811	21%
Twigs, Acacia koa	4.1	$T w B = \exp (- 6.7717 + 2.8829 \ln (D))$	0.905	65%
Twigs, Morella faya	19.7	$T w B = \exp (- 6.0928 + 3.3777 \ln (D))$	0.906	80%
Twigs, Dodonaea viscosa	0.7	$T w B = \exp (- 4.8233 + 2.4597 \ln (D))$	0.866	70%
Secondary stem, Robinia pseudoacacia	0.0	$S S B = \exp (- 5.7638 + 3.1684 \ln (D))$	0.947	46%
Secondary stem, Betula nigra	0.0	$S S B = \exp (- 6.6658 + 2.7654 \ln (D))$	0.777	96%
Secondary stem, Gliricidia sepium^†	N/A	N/A	N/A	N/A
Secondary stem, Casuarina equisetifolia	24.1	$S S B = \exp (- 6.5568 + 2.8451 \ln (D))$	0.802	116%
Secondary stem, Psidium cattleianum^†	N/A	N/A	N/A	N/A
Secondary stem, Acacia koa	7.6	$S S B = \exp (- 8.9775 + 4.4058 \ln (D))$	0.920	56%
Secondary stem, Morella faya^†	N/A	N/A	N/A	N/A
Secondary stem, Dodonaea viscosa^†	N/A	N/A	N/A	N/A
Main stem, Robinia pseudoacacia	0.6	$M S B = \exp (- 4.6278 + 2.7784 \ln (D))$	0.979	23%
Main stem, Betula nigra	35.1	$M S B = \exp (- 5.0817 + 2.5608 \ln (D))$	0.840	92%
Main stem, Gliricidia sepium	6.2	$M S B = \exp (- 5.9610 + 3.6987 \ln (D))$	0.963	64%
Main stem, Casuarina equisetifolia	10.5	$M S B = \exp (- 4.4247 + 2.4560 \ln (D))$	0.851	72%
Main stem, Psidium cattleianum	6.5	$M S B = \exp (- 7.8400 + 4.5330 \ln (D))$	0.746	51%
Main stem, Acacia koa	12.7	$M S B = \exp (- 4.7964 + 2.6322 \ln (D))$	0.977	24%
Main stem, Morella faya	22.3	$M S B = \exp (- 5.8015 + 3.5608 \ln (D))$	0.952	54%
Main stem, Dodonaea viscosa	4.0	$M S B = \exp (- 3.9096 + 2.5310 \ln (D))$	0.943	41%

*Difference in AIC value from the best fit model shown in Table 4. A ΔAIC value of greater than 2 is roughly analogous to a significantly worse fit [64].

^†No secondary stems.

^@ΔAIC values for the N-fixer and non-fixer fits are for the comparison between the functional type model and the species-level model for all trees rather than the fits with other drivers, as is the case for the fits for each species. Similarly, the adjusted R² values for the N-fixer and non-fixer fits are for the model with a functional type effect for all trees.