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Table 3 Results of mixed-effects models for the effects of neighbourhood tree species richness (NSR), exponential Shannon index (eHS), crown complementarity index (CCI) and target tree basal area (BAlog) on crown dimensions, branch length and wood volume based on the two tree neighbour selection approaches fixed radius and “overlapping crowns” (n target trees = 148). In all models BAlog p = .: p < 0.1; *: p < 0.05; **: p < 0.01; ***: p < 0.001; n.s. = not significant

From: Effects of local neighbourhood diversity on crown structure and productivity of individual trees in mature mixed-species forests

Response variable Fixed effects Fixed radius Overlapping crowns
Estimates p R2c Estimates p R2c
Crown volume (log) NSR + BAlog 0.08 + 0.98 * 0.89 0.09 + 0.95 * 0.89
eHS + BAlog 0.01 + 0.95 n.s. 0.89 0.08 + 0.96 * 0.89
CCI + BAlog 0.04 + 0.95 n.s. 0.89 −0.10 + 0.93 ** 0.89
Crown projection area (log) NSR + BAlog 0.04 + 0.70 n.s. 0.85 0.10 + 0.70 ** 0.86
eHS + BAlog −0.01 + 0.69 n.s. 0.85 0.08 + 0.71 * 0.86
CCI + BAlog 0.04 + 0.69 n.s. 0.85 −0.02 + 0.69 n.s. 0.84
Crown surface area (log) NSR + BAlog 0.06 + 0.93 n.s. 0.89 0.10 + 0.92 ** 0.90
eHS + BAlog 0.00 + 0.91 n.s. 0.89 0.08 + 0.93 * 0.90
CCI + BAlog 0.01 + 0.91 n.s. 0.89 −0.05 + 0.89 n.s. 0.89
Branch length sum (log) NSR + BAlog 0.09 + 0.70 n.s. 0.76 0.17 + 0.68 ** 0.77
eHS + BAlog 0.00 + 0.68 n.s. 0.75 0.13 + 0.69 * 0.77
CCI + BAlog 0.01 + 0.68 n.s. 0.76 −0.07 + 0.67 n.s. 0.74
Total wood volume (log) NSR + BAlog 0.02 + 0.96 n.s. 0.97 0.06 + 0.96 ** 0.97
eHS + BAlog 0.00 + 0.96 n.s. 0.97 0.05 + 0.96 ** 0.97
CCI + BAlog −0.03 + 0.96 n.s. 0.97 −0.05 + 0.95 *** 0.97
Fine woody material volume (log) NSR + BAlog 0.06 + 0.70 n.s. 0.81 0.14 + 0.69 ** 0.82
eHS + BAlog −0.01 + 0.69 n.s. 0.81 0.12 + 0.70 ** 0.82
CCI + BAlog −0.01 + 0.70 n.s. 0.81 −0.07 + 0.67 ** 0.80
Merchantable wood volume (log) NSR + BAlog 0.01 + 1.07 n.s. 0.98 0.03 + 1.06 . 0.98
eHS + BAlog 0.02 + 1.07 n.s. 0.98 0.03 + 1.06 . 0.98
CCI + BAlog −0.04 + 1.08 ** 0.98 −0.04 + 1.07 ** 0.98