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Table III
Path coefficients for the effects of tree size, neighboring competition and habitat factor on stem growth rate (SGR) for both genders at 10 neighborhood radii.
| Cause-effect relationships | Competition zone radius | ||||
|---|---|---|---|---|---|
|
|
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| r = 9–10 m | r = 5–8 m | r = 4 m | r = 3 m | r = 1–2 m | |
| Female plants | |||||
| Soil moisture → Neighboring competition by all trees | –0.04 | –0.04 | –0.04 | –0.04 | [–0.06, –0.05] |
| Soil moisture → Neighboring competition by males | [–0.25,–0.24]∗ | [–0.23,–0.19]∗ | –0.20∗ | –0.16 | –0.11 |
| Soil moisture → Neighboring competition by females | –0.07 | –0.07 | –0.07 | –0.07 | [–0.06, –0.05] |
| Soil moisture → SGR | 0.29∗∗ | [0.29,0.31]∗∗ | 0.32∗∗∗ | 0.32∗∗∗ | 0.32∗∗∗ |
| Neighboring competition by all trees → SGR | [0.17, 0.18] | [0.18, 0.21] | 0.23 | 0.28 | [0.22, 0.24] |
| Neighboring competition by males → SGR | –0.09 | [–0.01, –0.09] | 0.06 | 0.01 | 0.03 |
| Neighboring competition by females → SGR | [–0.19,–0.18]∗ | [–0.23,–0.20]∗ | –0.24∗ | –0.29∗ | [–0.25,–0.22]∗ |
| Tree size → SGR | 0.30∗∗∗ | [0.30,0.31]∗∗∗ | 0.31∗∗∗ | 0.32∗∗∗ | [0.31,0.32]∗∗∗ |
| Neighboring competition by females → Neighboring competition by all trees | 0.88∗∗∗ | [0.88,0.90]∗∗∗ | 0.90∗∗∗ | 0.92∗∗∗ | [0.84,0.87]∗∗∗ |
| Neighboring competition by males → Neighboring competition by all trees | [–0.02, –0.01] | [–0.02, –0.01] | –0.01 | 0.01 | [–0.025, 0] |
| Male plants | |||||
| Soil moisture → Neighboring competition by all trees | 0.06 | 0.06 | 0.058 | 0.059 | 0.05 |
| Soil moisture → Neighboring competition by males | [–0.17, –0.15] | [–0.19, –0.11] | –0.15 | –0.134 | [–0.11, 0] |
| Soil moisture → Neighboring competition by females | –0.04 | –0.04 | –0.035 | –0.035 | [–0.04, –0.03] |
| Soil moisture → SGR | 0.23∗∗ | [0.23,0.25]∗∗ | 0.239∗∗ | 0.241∗∗ | 0.26∗∗ |
| Neighboring competition by all trees → SGR | [–0.09, –0.08] | [–0.09, –0.08] | –0.085 | –0.076 | –0.09 |
| Neighboring competition by males → SGR | [–0.25,–0.22]∗∗ | [–0.21,–0.16]∗ | –0.162∗ | –0.157∗ | [–0.06, 0] |
| Neighboring competition by females → SGR | [–0.07, –0.06] | [–0.07, –0.06] | –0.058 | –0.075 | –0.05 |
| Tree size → SGR | [0.43,0.44]∗∗∗ | [0.44,0.46]∗∗∗ | 0.466∗∗∗ | 0.464∗∗∗ | 0.49∗∗∗ |
| Neighboring competition by females → Neighboring competition by all trees | 0.80∗∗∗ | 0.80∗∗∗ | 0.794∗∗∗ | 0.798∗∗∗ | 0.79∗∗∗ |
| Neighboring competition by males → Neighboring competition by all trees | 0.01 | [0, 0.03] | 0.024 | 0.043 | [–0.03, 0] |
Tree size was presented by dbh in 2005; Stem growth rate (SGR, cm/5 years) was calculated with radius increment at breast height from 2003 to 2007. The figures in the square brackets refer to the range of the path coefficient. The path coefficient describes the estimated strength of effects between variables. Larger absolute values of the path coefficient indicate higher strength. The positive and negative signs indicate positive and negative causality respectively.