226 Lee: Prediction of Pavement Damages Associated with Urban Trees Table 5. Multiple regression results for predicting the length of (a) protruding roots, (b) protruding flares, and (c) protruding roots and/or flares. Diameter at breast height and tree height were abbreviated as DBH and H. R2 (a) Protruding roots only A. moluccanus B. ceiba C. equisetifolia C. burmannii D. regia F. altissima F. microcarpa M. cajuputi S. campanulata All trees (b) Protruding flares only A. moluccanus B. ceiba C. equisetifolia C. burmannii D. regia F. altissima F. microcarpa M. cajuputi S. campanulata All trees (c) Protruding roots and/or flares A. moluccanus B. ceiba C. equisetifolia C. burmannii D. regia F. altissima F. microcarpa M. cajuputi S. campanulata All trees 0.203 0.285 0.192 0.668 0.639 0.338 0.017 0.624 0.502 0.207 0.127 0.124 0.449 0.164 0.590 0.294 0.479 0.759 0.756 0.577 0.398 0.167 0.196 0.475 0.633 0.359 0.098 0.662 0.630 0.311 Intercept DBH 0.711 −0.039 0.451 0.519 −0.012 1.069 −0.032 0.132 0.849 0.219 0.239 0.627 0.405 0.386 0.347 2.290 0.320 0.014 −0.595 0.306 0.660 0.428 0.134 0.237 0.397 1.509 −0.207 0.126 −0.319 0.185 H −0.038 −0.782 −0.882 0.684 0.422 −0.084 0.730 0.373 −0.750 0.024 −1.425 −0.602 0.516 0.675 0.026 −0.005 0.511 −1.193 −0.835 0.051 −0.745 −0.010 0.312 0.536 1.072 −0.051 1.110 0.432 −0.364 0.164 −0.002 0.060 0.026 −0.017 −0.018 0.017 0 0.008 −0.010 0.007 −0.009 0.002 −0.029 0.002 −0.016 0.001 −0.008 −0.013 0.030 0 0.006 0.009 −0.008 0.001 −0.053 0.008 −0.001 −0.002 0.013 0.003 Lean Pavement Open soil angle 0.004 0.041 0.006 0.002 width −0.022 0.043 0.013 −0.095 −0.020 −0.043 −0.004 −0.166 −0.005 0.007 0.032 0.010 −0.003 −0.020 0 −0.004 0.002 0.015 0.004 0.003 −0.009 0.306 −0.066 −0.024 0.043 −0.009 −0.115 0.004 0.016 0.019 0.007 0.004 0.028 0.013 0.003 0.007 −0.046 0.007 −0.007 0.037 −0.014 0.016 −0.062 −0.002 −0.007 −0.066 −0.010 −0.158 0.001 0.009 0.015 0.008 0.035 0.010 0.012 −0.014 area 0.091 0.018 −0.048 0.292 0.168 0.099 0.119 0.246 0.428 0.165 0.157 0.276 0.195 −0.224 0.234 0.078 0.142 0.492 0.416 0.154 0.169 0.158 0.148 0.207 0.220 0.103 0.130 0.266 0.446 0.172 Pavement Setback material −0.454 −0.050 0 0.102 0.086 0.267 −0.053 0.069 −0.054 0.006 −0.623 0.116 0.076 −0.081 0.034 0.101 −0.027 0.095 −0.020 0.001 −0.427 0.063 0.050 −0.016 0.068 0.208 −0.064 0.071 −0.015 0.002 −0.003 0 N/A −0.018 0.713 −0.223 0.321 −0.076 −0.206 0.158 0.006 −0.116 N/A 0.111 0.205 −0.952 0.080 0.292 0.222 0.092 −0.013 −0.053 N/A 0.024 0.286 −0.311 0.327 −0.019 0.127 0.159 In each scenario, if more than 1 protrusion was detected on a tree, only the longest protruding parts were considered. Species-specific regression coefficients of the predictors, namely DBH, H, lean angle, pavement width, open soil area, setback, and pavement material, were presented. If significant, the adjusted R2 and regression coefficient values were italicised and underlined. “N/A” indicated a lack of variation. A. alexandrae, L. speciosa, M. × alba, P. serratifolia, and X. chrysanthus were excluded due to small sample size. DISCUSSION Measurement Method of Trunk Flare TFD prediction models in Table 2 were corroborated by previous studies in the sense that DBH was the critical predictor of TFD (North et al. 2015; Hilbert et al. 2020). However, in terms of R2 values from DBH- TFD models, the past researchers reported much- higher values (R2 research (R2 > 0.80) than those in the present ≤ 0.792), except for A. alexandrae. How- ever, most of the regression coefficients of DBH in this study, which were up to 4.495 m, exceeded the values documented in the previous studies (1.3 to 1.9 m). In short, DBH showed a stronger effect in TFD pre- diction models with lower R2 than in past research. The discrepancy could be caused by the difference in measurement methods. In previous research, TFD was marked at the points of transition from trunk to root at ground level. However, in the current research, protruding roots and/or flares were observed to encroach on pavement surface. As the outermost points of protruding roots and/or flares, if present, were used in the measurement of TFD (Figure 2), larger TFD values with greater variability could thus ©2022 International Society of Arboriculture
July 2022
| Title Name |
Pages |
Delete |
Url |
| Empty |
Ai generated response may be inaccurate.
Search Text Block
Page #page_num
#doc_title
Hi $receivername|$receiveremail,
$sendername|$senderemail wrote these comments for you:
$message
$sendername|$senderemail would like for you to view the following digital edition.
Please click on the page below to be directed to the digital edition:
$thumbnail$pagenum
$link$pagenum
Your form submission was a success.
Downloading PDF
Generating your PDF, please wait...
This process might take longer please wait
