Allometric equations for estimating belowground biomass of Androstachys johnsonii Prain

Table 4 Coefficients of regression (± standard error) for independently fitted models

Model form #	Weight function	b₀ (±SE)	b₁ (±SE)	b₂ (±SE)
Root collar
1	1/0.0002 × DBH^3.6194	0.0129 (±0.0040)**	2.3350 (±0.1024)***
2	1/0.0001 × DBH^3.6750	0.0035 (±0.0030)^ns	2.0979 (±0.1606)***	0.7807 (±0.4478)^ns
3	1/0.0358 × exp(0.2527 × DBH)	0.0024 (±0.0010)*	1.0143 (± 0.0497)***
4	1/0.0352 × exp(0.2219 × RCD)	0.0064 (±0.0024)**	2.4946 (± 0.1216)***
Taproot
1	1/0.0002 × DBH^3.7383	0.0427 (±0.0103)***	2.0594 (±0.0840)***
2	1/0.0002 × DBH^3.7521	0.0092 (±0.0066)^ns	1.7587 (±0.1447)***	0.9442 (±0.3989)*
3	1/0.0001 × DBH^3.8793	0.0101 (±0.0029)***	0.8885 (±0.0353)***
4	1/0.0002 × RCD^3.6082	0.0269 (±0.0074)***	2.1454 (±0.0910)***
Lateral roots
1	1/0.000008 × DBH^4.8739	0.0099 (±0.0021)***	2.6041 (±0.0748)***
2	1/0.00007 × DBH^4.0862	0.0045 (±0.0028)^ns	2.5257 (±0.1213)***	0.3983 (±0.3265)^ns
3	1/0.00006 × DBH^4.1635	0.0012 (±0.0004)**	1.1585 (±0.0369)***
4	1/0.0189 × exp(0.2826 × RCD)	0.0038 (±0.0011)***	2.8352 (±0.0975)***
Root system
1	1/0.00007 × DBH^4.3051	0.0405 (±0.0064)***	2.3402 (±0.0545)***
2	1/0.000008 × DBH^1.7645	0.0185 (±0.0064)**	2.1990 (±0.0793)***	0.4699 (±0.1898)*
3	1/0.0003 × DBH^3.8639	0.0070 (±0.0015)***	1.0226 (±0.0251)***
4	1/0.00007 × RCD^4.2484	0.0230 (±0.0042)***	2.4519 (±0.0608)***

ISSN: 1750-0680