The relationships among structure variables of larch forests in China

Forest Ecosystems

Table 4 The parameters of the quantile regression (QR) and the ordinary least square regression (OLS) between taper and stem density for larch forests in China

Forest type	Exponent f (mean ± standard error)
Forest type	OLS	50% quantile	75% quantile	95% quantile
L. gmelinii	− 0.27 ± 0.06^**	−0.29 ± 0.09^**	−0.30 ± 0.06^**	−0.19 ± 0.05^**
L. gmelinii var. principis -rupprechtii	− 0.23 ± 0.08^**	−0.12 ± 0.12	−0.18 ± 0.10	−0.31 ± 0.09^**
L. olgensis ^a	–	–	–	–
L. sibirica	−0.33 ± 0.07^**	−0.27 ± 0.07^**	−0.33 ± 0.11^**	−0.53 ± 0.12^**
L. griffithii	− 1.31 ± 0.83	− 1.83 ± 1.68	−2.55 ± 2.05	−2.55 ± 1.98
L. himalaica	−0.38 ± 0.14	−0.32 ± 0.28	−0.46 ± 0.32	−0.46 ± 0.35
L. mastersiana	− 0.27 ± 0.11	−0.21 ± 1.30	−0.34 ± 1.62	−0.34 ± 1.56
L. potaninii	− 0.18 ± 0.25	−0.07 ± 1.20	−0.26 ± 1.48	−0.26 ± 1.12
L. potaninii var. australis	− 0.35 ± 0.24	−0.35 ± 0.32	−0.56 ± 0.49	−0.72 ± 0.69
L. potaninii var. chinensis	0.14 ± 0.23	−0.05 ± 0.28	−0.20 ± 0.27	0.21 ± 0.38
L. speciose ^a	–	–	–	–
Sect. Larix	−0.33 ± 0.05^**	−0.33 ± 0.04^**	−0.39 ± 0.11^**	−0.37 ± 0.09^**
Sect. Multiseriales	0.06 ± 0.14	0.05 ± 0.15	0.03 ± 0.22	0.05 ± 0.25
Overall	−0.43 ± 0.06^**	−0.47 ± 0.06^**	−0.42 ± 0.10^**	−0.70 ± 0.20^**

The f is the parameter of Eq. 5. ^aindicates larch forest types with the number of plots less than 3. ^** and ^* indicate p < 0.01 and p < 0.05, respectively