Table S1. Allometric equations [ln(CRB) = a+b×ln(DBH)] and [ln(CRB) = a+b×DBH] relating coarse root biomass (CRB) to diameter at breast height (DBH) for nine tree species. a and b are allometric coefficients with standard errors in parentheses. R2 is the coefficient of determination; RMSE is root mean square error; FI is the Furnival index; and AIC is Akaike’s information criterion.

Tree species / Allometric equations / a(Se) / b(Se) / R2 / p value / RMSE / FI / AIC
Pinus massoniana / ln(CRB)=a+bln×(DBH) / -4.17(0.26) / 2.40(0.09) / 0.97 / <0.0001 / 0.35 / 2.72 / 23.75
ln(CRB)=a+b×DBH / -0.48(0.36) / 0.15(0.01) / 0.81 / <0.0001 / 0.88 / 6.78 / 71.20
Alniphyllum fortunei / ln(CRB)=a+bln×(DBH) / -5.04(0.49) / 2.78(0.17) / 0.97 / <0.0001 / 0.39 / 2.77 / 13.18
ln(CRB)=a+b×DBH / -0.70(0.52) / 0.17(0.02) / 0.89 / <0.0001 / 0.77 / 5.50 / 26.90
Choerospondias axillaris / ln(CRB)=a+bln×(DBH) / -2.17(1.05) / 2.00(0.43) / 0.73 / <0.05 / 0.81 / 5.78 / 27.88
ln(CRB)=a+b×DBH / 0.43(0.65) / 0.17(0.04) / 0.64 / <0.05 / 0.94 / 6.73 / 30.92
Liquidambar formosana / ln(CRB)=a+bln×(DBH) / -3.61(0.68) / 2.35(0.23) / 0.84 / <0.0001 / 0.61 / 4.68 / 43.04
ln(CRB)=a+b×DBH / 0.65(0.20) / 0.12(0.01) / 0.92 / <0.0001 / 0.44 / 3.37 / 29.25
Quercus fabri / ln(CRB)=a+bln×(DBH) / -5.72(0.76) / 3.06(0.27) / 0.95 / <0.0001 / 0.36 / 2.46 / 9.86
ln(CRB)=a+b×DBH / -0.21(0.28) / 0.17(0.01) / 0.96 / <0.0001 / 0.34 / 2.41 / 9.51
Castanopsis carlesii / ln(CRB)=a+bln×(DBH) / -4.25(0.76) / 2.59(0.28) / 0.95 / <0.05 / 0.39 / 2.67 / 10.48
ln(CRB)=a+b×DBH / -0.07(0.42) / 0.17(0.02) / 0.91 / <0.05 / 0.49 / 3.35 / 13.66
Cyclobalanopsis glauca / ln(CRB)=a+bln×(DBH) / -4.15(0.33) / 2.71(0.13) / 0.95 / <0.0001 / 0.46 / 3.55 / 37.48
ln(CRB)=a+b×DBH / 0.37(0.27) / 0.14(0.01) / 0.84 / <0.0001 / 0.84 / 6.44 / 68.53
Litsea coreana / ln(CRB)=a+bln×(DBH) / -2.29(0.42) / 1.99(0.14) / 0.96 / <0.0001 / 0.39 / 2.78 / 13.22
ln(CRB)=a+b×DBH / 0.87(0.61) / 0.11(0.02) / 0.75 / <0.05 / 0.99 / 7.11 / 32.03
Schima superba / ln(CRB)=a+bln×(DBH) / -3.37(0.40) / 2.33(0.15) / 0.95 / <0.0001 / 0.37 / 2.73 / 16.26
ln(CRB)=a+b×DBH / 0.33(0.34) / 0.15(0.02) / 0.84 / <0.0001 / 0.65 / 4.85 / 33.54

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