Spatiotemporal variations in productivity and water use efficiency across a temperate forest landscape of Northeast China

Forest Ecosystems

Table 2 Summary of multiple linear regression for the effects of biotic and abiotic factors on the spatial variations of mean annual NPP, ET and WUE for the period 2000–2014 across the forest landscape in Lushuihe of Jilin Province, Northeast China. SOC, soil organic carbon; T_mean, mean annual air temperature; T_max, mean annual maximum air temperature; T_min, mean annual minimum air temperature

Explanatory variables	NPP		t-value	p-value	ET		t-value	p-value	WUE		t-value	p-value
Explanatory variables	Estimate	SE	t-value	p-value	Estimate	SE	t-value	p-value	Estimate	SE	t-value	p-value
Establishment mode	−7.383	1.259	−5.863	< 0.001	4.237	1.314	3.223	0.001	−0.020	0.004	−5.157	< 0.001
Forest type	5.243	0.474	11.065	< 0.001	−4.982	0.495	−10.073	< 0.001	0.017	0.001	11.517	< 0.001
Age class	2.307	0.395	5.839	< 0.001	−3.183	0.412	−7.718	< 0.001	0.009	0.001	7.523	< 0.001
Stand density	0.005	0.001	3.930	< 0.001	−0.003	0.001	−2.302	0.021	0.000	0.000	3.512	< 0.001
Elevation	0.007	0.004	1.899	0.058	−0.005	0.004	−1.282	0.200	0.000	0.000	1.187	0.235
Aspect	0.001	0.003	0.213	0.832	0.001	0.003	0.394	0.693	0.000	0.000	−0.195	0.845
Slope	0.127	0.062	2.063	0.039	−0.083	0.064	−1.285	0.199	0.000	0.000	1.906	0.057
Slope position	−0.062	0.300	−0.206	0.837	1.742	0.313	5.560	< 0.001	−0.003	0.001	−3.102	0.002
SOC	−7.033	1.706	−4.123	< 0.001	−2.217	1.780	−1.245	0.213	−0.011	0.005	−2.081	0.037
Precipitation	0.076	0.122	0.626	0.531	0.292	0.127	2.302	0.021	0.000	0.000	−1.242	0.214
T _mean	1028.698	56.718	18.137	< 0.001	− 1125.973	59.197	−19.021	< 0.001	3.506	0.175	19.978	< 0.001
T _max	−317.054	37.895	−8.367	< 0.001	417.860	39.552	10.565	< 0.001	−1.228	0.117	− 10.473	< 0.001
T _min	− 712.860	33.763	−21.114	< 0.001	702.818	35.238	19.945	< 0.001	−2.270	0.104	−21.724	< 0.001