Analysis of Taper Functions for <i>Larix olgensis</i> Using Mixed Models and TLS
Terrestrial laser scanning (TLS) plays a significant role in forest resource investigation, forest parameter inversion and tree 3D model reconstruction. TLS can accurately, quickly and nondestructively obtain 3D structural information of standing trees. TLS data, rather than felled wood data, were u...
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2021-02-01
|
| Series: | Forests |
| Subjects: | |
| Online Access: | https://www.mdpi.com/1999-4907/12/2/196 |
| _version_ | 1797412820671791104 |
|---|---|
| author | Dandan Li Haotian Guo Weiwei Jia Fan Wang |
| author_facet | Dandan Li Haotian Guo Weiwei Jia Fan Wang |
| author_sort | Dandan Li |
| collection | DOAJ |
| description | Terrestrial laser scanning (TLS) plays a significant role in forest resource investigation, forest parameter inversion and tree 3D model reconstruction. TLS can accurately, quickly and nondestructively obtain 3D structural information of standing trees. TLS data, rather than felled wood data, were used to construct a mixed model of the taper function based on the tree effect, and the TLS data extraction and model prediction effects were evaluated to derive the stem diameter and volume. TLS was applied to a total of 580 trees in the nine larch (<i>Larix olgensis</i>) forest plots, and another 30 were applied to a stem analysis in Mengjiagang. First, the diameter accuracies at different heights of the stem analysis were analyzed from the TLS data. Then, the stem analysis data and TLS data were used to establish the stem taper function and select the optimal basic model to determine a mixed model based on the tree effect. Six basic models were fitted, and the taper equation was comprehensively evaluated by various statistical metrics. Finally, the optimal mixed model of the plot was used to derive stem diameters and trunk volumes. The stem diameter accuracy obtained by TLS was >98%. The taper function fitting results of these data were approximately the same, and the optimal basic model was Kozak (2002)-II. For the tree effect, <i>a</i><sub>6</sub> and <i>a</i><sub>9</sub> were used as the mixed parameters, the mixed model showed the best fit, and the accuracy of the optimal mixed model reached 99.72%.The mixed model accuracy for predicting the tree diameter was between 74.22% and 97.68%, with a volume estimation accuracy of 96.38%. Relative height 70 (RH70) was the optimum height for extraction, and the fitting accuracy of the mixed model was higher than that of the basic model. |
| first_indexed | 2024-03-09T05:08:45Z |
| format | Article |
| id | doaj.art-1e1e38c489e6466281b17ee300a685ff |
| institution | Directory Open Access Journal |
| issn | 1999-4907 |
| language | English |
| last_indexed | 2024-03-09T05:08:45Z |
| publishDate | 2021-02-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Forests |
| spelling | doaj.art-1e1e38c489e6466281b17ee300a685ff2023-12-03T12:51:15ZengMDPI AGForests1999-49072021-02-0112219610.3390/f12020196Analysis of Taper Functions for <i>Larix olgensis</i> Using Mixed Models and TLSDandan Li0Haotian Guo1Weiwei Jia2Fan Wang3Department of Forest Management, School of Forestry, Northeast Forestry University, Harbin 150040, ChinaDepartment of Forest Management, School of Forestry, Northeast Forestry University, Harbin 150040, ChinaDepartment of Forest Management, School of Forestry, Northeast Forestry University, Harbin 150040, ChinaDepartment of Forest Management, School of Forestry, Northeast Forestry University, Harbin 150040, ChinaTerrestrial laser scanning (TLS) plays a significant role in forest resource investigation, forest parameter inversion and tree 3D model reconstruction. TLS can accurately, quickly and nondestructively obtain 3D structural information of standing trees. TLS data, rather than felled wood data, were used to construct a mixed model of the taper function based on the tree effect, and the TLS data extraction and model prediction effects were evaluated to derive the stem diameter and volume. TLS was applied to a total of 580 trees in the nine larch (<i>Larix olgensis</i>) forest plots, and another 30 were applied to a stem analysis in Mengjiagang. First, the diameter accuracies at different heights of the stem analysis were analyzed from the TLS data. Then, the stem analysis data and TLS data were used to establish the stem taper function and select the optimal basic model to determine a mixed model based on the tree effect. Six basic models were fitted, and the taper equation was comprehensively evaluated by various statistical metrics. Finally, the optimal mixed model of the plot was used to derive stem diameters and trunk volumes. The stem diameter accuracy obtained by TLS was >98%. The taper function fitting results of these data were approximately the same, and the optimal basic model was Kozak (2002)-II. For the tree effect, <i>a</i><sub>6</sub> and <i>a</i><sub>9</sub> were used as the mixed parameters, the mixed model showed the best fit, and the accuracy of the optimal mixed model reached 99.72%.The mixed model accuracy for predicting the tree diameter was between 74.22% and 97.68%, with a volume estimation accuracy of 96.38%. Relative height 70 (RH70) was the optimum height for extraction, and the fitting accuracy of the mixed model was higher than that of the basic model.https://www.mdpi.com/1999-4907/12/2/196TLSdiameter at the relative heighttaper functionmixed model |
| spellingShingle | Dandan Li Haotian Guo Weiwei Jia Fan Wang Analysis of Taper Functions for <i>Larix olgensis</i> Using Mixed Models and TLS Forests TLS diameter at the relative height taper function mixed model |
| title | Analysis of Taper Functions for <i>Larix olgensis</i> Using Mixed Models and TLS |
| title_full | Analysis of Taper Functions for <i>Larix olgensis</i> Using Mixed Models and TLS |
| title_fullStr | Analysis of Taper Functions for <i>Larix olgensis</i> Using Mixed Models and TLS |
| title_full_unstemmed | Analysis of Taper Functions for <i>Larix olgensis</i> Using Mixed Models and TLS |
| title_short | Analysis of Taper Functions for <i>Larix olgensis</i> Using Mixed Models and TLS |
| title_sort | analysis of taper functions for i larix olgensis i using mixed models and tls |
| topic | TLS diameter at the relative height taper function mixed model |
| url | https://www.mdpi.com/1999-4907/12/2/196 |
| work_keys_str_mv | AT dandanli analysisoftaperfunctionsforilarixolgensisiusingmixedmodelsandtls AT haotianguo analysisoftaperfunctionsforilarixolgensisiusingmixedmodelsandtls AT weiweijia analysisoftaperfunctionsforilarixolgensisiusingmixedmodelsandtls AT fanwang analysisoftaperfunctionsforilarixolgensisiusingmixedmodelsandtls |