Crown Structure Metrics to Generalize Aboveground Biomass Estimation Model Using Airborne Laser Scanning Data in National Park of Hainan Tropical Rainforest, China
Forest aboveground biomass (AGB) is an important indicator for characterizing forest ecosystem structures and functions. Therefore, how to effectively investigate forest AGB is a vital mission. Airborne laser scanning (ALS) has been demonstrated as an effective way to support investigation and opera...
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| Format: | Article |
| Language: | English |
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MDPI AG
2022-07-01
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| Series: | Forests |
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| Online Access: | https://www.mdpi.com/1999-4907/13/7/1142 |
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| author | Chenyun Li Zhexiu Yu Shaojie Wang Fayun Wu Kunjian Wen Jianbo Qi Huaguo Huang |
| author_facet | Chenyun Li Zhexiu Yu Shaojie Wang Fayun Wu Kunjian Wen Jianbo Qi Huaguo Huang |
| author_sort | Chenyun Li |
| collection | DOAJ |
| description | Forest aboveground biomass (AGB) is an important indicator for characterizing forest ecosystem structures and functions. Therefore, how to effectively investigate forest AGB is a vital mission. Airborne laser scanning (ALS) has been demonstrated as an effective way to support investigation and operational applications among a wide range of applications in the forest inventory. Moreover, three-dimensional structure information relating to AGB can be acquired by airborne laser scanning. Many studies estimated AGB from variables that were extracted from point cloud data, but few of them took full advantage of variables related to tree crowns to estimate the AGB. In this study, the main objective was to evaluate and compare the capabilities of different metrics derived from point clouds obtained from ALS. Particularly, individual tree-based alpha-shape, along with other traditional and commonly used plot-level height and intensity metrics, have been used from airborne laser scanning data. We took the random forest and multiple stepwise linear regression to estimate the AGB. By comparing AGB estimates with field measurements, our results showed that the best approach is mixed metrics, and the best estimation model is random forest (<i>R</i><sup>2</sup> = 0.713, RMSE = 21.064 t/ha, MAE = 15.445 t/ha), which indicates that alpha-shape may be a good alternative method to improve AGB estimation accuracy. This method provides an effective solution for estimating aboveground biomass from airborne laser scanning. |
| first_indexed | 2024-03-09T03:24:45Z |
| format | Article |
| id | doaj.art-babba5cf1f364712858f2ca37c896652 |
| institution | Directory Open Access Journal |
| issn | 1999-4907 |
| language | English |
| last_indexed | 2024-03-09T03:24:45Z |
| publishDate | 2022-07-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Forests |
| spelling | doaj.art-babba5cf1f364712858f2ca37c8966522023-12-03T15:04:26ZengMDPI AGForests1999-49072022-07-01137114210.3390/f13071142Crown Structure Metrics to Generalize Aboveground Biomass Estimation Model Using Airborne Laser Scanning Data in National Park of Hainan Tropical Rainforest, ChinaChenyun Li0Zhexiu Yu1Shaojie Wang2Fayun Wu3Kunjian Wen4Jianbo Qi5Huaguo Huang6Industry Development and Planning Institute, National Forestry and Grassland Administration, Beijing 100010, ChinaResearch Center of Forest Management Engineering of State Forestry and Grassland Administration, Beijing Forestry University, Beijing 100083, ChinaIndustry Development and Planning Institute, National Forestry and Grassland Administration, Beijing 100010, ChinaAcademy of Inventory and Planning, National Forestry and Grassland Administration, Beijing 100714, ChinaResearch Center of Forest Management Engineering of State Forestry and Grassland Administration, Beijing Forestry University, Beijing 100083, ChinaResearch Center of Forest Management Engineering of State Forestry and Grassland Administration, Beijing Forestry University, Beijing 100083, ChinaResearch Center of Forest Management Engineering of State Forestry and Grassland Administration, Beijing Forestry University, Beijing 100083, ChinaForest aboveground biomass (AGB) is an important indicator for characterizing forest ecosystem structures and functions. Therefore, how to effectively investigate forest AGB is a vital mission. Airborne laser scanning (ALS) has been demonstrated as an effective way to support investigation and operational applications among a wide range of applications in the forest inventory. Moreover, three-dimensional structure information relating to AGB can be acquired by airborne laser scanning. Many studies estimated AGB from variables that were extracted from point cloud data, but few of them took full advantage of variables related to tree crowns to estimate the AGB. In this study, the main objective was to evaluate and compare the capabilities of different metrics derived from point clouds obtained from ALS. Particularly, individual tree-based alpha-shape, along with other traditional and commonly used plot-level height and intensity metrics, have been used from airborne laser scanning data. We took the random forest and multiple stepwise linear regression to estimate the AGB. By comparing AGB estimates with field measurements, our results showed that the best approach is mixed metrics, and the best estimation model is random forest (<i>R</i><sup>2</sup> = 0.713, RMSE = 21.064 t/ha, MAE = 15.445 t/ha), which indicates that alpha-shape may be a good alternative method to improve AGB estimation accuracy. This method provides an effective solution for estimating aboveground biomass from airborne laser scanning.https://www.mdpi.com/1999-4907/13/7/1142tree crownalpha-shapeairborne laser scanning (ALS) |
| spellingShingle | Chenyun Li Zhexiu Yu Shaojie Wang Fayun Wu Kunjian Wen Jianbo Qi Huaguo Huang Crown Structure Metrics to Generalize Aboveground Biomass Estimation Model Using Airborne Laser Scanning Data in National Park of Hainan Tropical Rainforest, China Forests tree crown alpha-shape airborne laser scanning (ALS) |
| title | Crown Structure Metrics to Generalize Aboveground Biomass Estimation Model Using Airborne Laser Scanning Data in National Park of Hainan Tropical Rainforest, China |
| title_full | Crown Structure Metrics to Generalize Aboveground Biomass Estimation Model Using Airborne Laser Scanning Data in National Park of Hainan Tropical Rainforest, China |
| title_fullStr | Crown Structure Metrics to Generalize Aboveground Biomass Estimation Model Using Airborne Laser Scanning Data in National Park of Hainan Tropical Rainforest, China |
| title_full_unstemmed | Crown Structure Metrics to Generalize Aboveground Biomass Estimation Model Using Airborne Laser Scanning Data in National Park of Hainan Tropical Rainforest, China |
| title_short | Crown Structure Metrics to Generalize Aboveground Biomass Estimation Model Using Airborne Laser Scanning Data in National Park of Hainan Tropical Rainforest, China |
| title_sort | crown structure metrics to generalize aboveground biomass estimation model using airborne laser scanning data in national park of hainan tropical rainforest china |
| topic | tree crown alpha-shape airborne laser scanning (ALS) |
| url | https://www.mdpi.com/1999-4907/13/7/1142 |
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