Climate change-associated trends in biomass dynamics are consistent across soil drainage classes in western boreal forests of Canada

Forest Ecosystems

Table 3 The responses (P values) of absolute and relative growth, mortality, and net biomass change to atmospheric CO₂ (CO₂), mean annual temperature anomaly (ATA) and standardized precipitation evapotranspiration index (SPEI), drainage class, and forest age

Fixed effects	Biomass gain from growth (Mg ha⁻¹ year⁻¹)	Biomass loss from mortality (Mg ha⁻¹ year⁻¹)	Net biomass change (Mg ha⁻¹ year⁻¹)	Biomass gain from growth (% year⁻¹)	Biomass loss from mortality (% year⁻¹)	Net biomass change (% year⁻¹)
Atmospheric carbon dioxide concentration
D	0.094	0.002	0.017	0.017	0.035	<0.001
f(A)	<0.001	<0.001	<0.001	<0.001	<0.001	<0.001
CO ₂	0.008	<0.001	<0.001	<0.001	<0.001	<0.001
D × f(A)	0.976	<0.001	<0.001	<0.001	0.005	<0.001
D × CO ₂	0.066	0.158	0.032	<0.001	0.490	<0.001
f(A) × CO ₂	0.046	0.683	0.974	<0.001	0.055	0.002
Annual temperature anomaly
D	0.122	0.003	0.030	0.073	0.051	<0.001
f(A)	<0.001	<0.001	<0.001	<0.001	<0.001	<0.001
ATA	0.373	0.002	0.002	0.006	0.009	<0.001
D × f(A)	0.889	<0.001	<0.001	<0.001	0.015	<0.001
D × ATA	0.336	0.882	0.877	<0.001	0.747	0.100
f(A) × ATA	0.086	0.036	0.207	<0.001	0.001	0.867
Standardized precipitation-evapotranspiration index
D	0.138	0.004	0.027	0.044	0.046	<0.001
f(A)	<0.001	<0.001	<0.001	<0.001	<0.001	<0.001
SPEI	0.114	0.021	0.006	0.159	0.005	0.004
D × f(A)	0.517	<0.001	<0.001	0.001	0.002	<0.001
D × SPEI	0.179	0.650	0.618	0.041	0.582	0.065
f(A) × SPEI	0.337	0.010	0.026	<0.001	0.048	0.020

f(A) represents the natural logarithm of forest age for absolute rates and the inverse of the natural logarithm of forest age for relative rates