Tree Biomass Equations from Terrestrial LiDAR: A Case Study in Guyana

Large uncertainties in tree and forest carbon estimates weaken national efforts to accurately estimate aboveground biomass (AGB) for their national monitoring, measurement, reporting and verification system. Allometric equations to estimate biomass have improved, but remain limited. They rely on des...

Full description

Bibliographic Details
Main Authors: Lau, A., Calders, K., Bartholomeus, H., Martius, C., Raumonen, P., Herold, M., Vicari, M., Sukhdeo, H., Singh, J., Goodman, R.C.
Format: Journal Article
Language:Inglés
Published: MDPI 2019
Subjects:
Online Access:https://hdl.handle.net/10568/112152
_version_ 1855528605917904896
author Lau, A.
Calders, K.
Bartholomeus, H.
Martius, C.
Raumonen, P.
Herold, M.
Vicari, M.
Sukhdeo, H.
Singh, J.
Goodman, R.C.
author_browse Bartholomeus, H.
Calders, K.
Goodman, R.C.
Herold, M.
Lau, A.
Martius, C.
Raumonen, P.
Singh, J.
Sukhdeo, H.
Vicari, M.
author_facet Lau, A.
Calders, K.
Bartholomeus, H.
Martius, C.
Raumonen, P.
Herold, M.
Vicari, M.
Sukhdeo, H.
Singh, J.
Goodman, R.C.
author_sort Lau, A.
collection Repository of Agricultural Research Outputs (CGSpace)
description Large uncertainties in tree and forest carbon estimates weaken national efforts to accurately estimate aboveground biomass (AGB) for their national monitoring, measurement, reporting and verification system. Allometric equations to estimate biomass have improved, but remain limited. They rely on destructive sampling; large trees are under-represented in the data used to create them; and they cannot always be applied to different regions. These factors lead to uncertainties and systematic errors in biomass estimations. We developed allometric models to estimate tree AGB in Guyana. These models were based on tree attributes (diameter, height, crown diameter) obtained from terrestrial laser scanning (TLS) point clouds from 72 tropical trees and wood density. We validated our methods and models with data from 26 additional destructively harvested trees. We found that our best TLS-derived allometric models included crown diameter, provided more accurate AGB estimates ( R 2 = 0.92–0.93) than traditional pantropical models ( R 2 = 0.85–0.89), and were especially accurate for large trees (diameter > 70 cm). The assessed pantropical models underestimated AGB by 4 to 13%. Nevertheless, one pantropical model (Chave et al. 2005 without height) consistently performed best among the pantropical models tested ( R 2 = 0.89) and predicted AGB accurately across all size classes—which but for this could not be known without destructive or TLS-derived validation data. Our methods also demonstrate that tree height is difficult to measure in situ, and the inclusion of height in allometric models consistently worsened AGB estimates. We determined that TLS-derived AGB estimates were unbiased. Our approach advances methods to be able to develop, test, and choose allometric models without the need to harvest trees.
format Journal Article
id CGSpace112152
institution CGIAR Consortium
language Inglés
publishDate 2019
publishDateRange 2019
publishDateSort 2019
publisher MDPI
publisherStr MDPI
record_format dspace
spelling CGSpace1121522024-06-26T09:37:12Z Tree Biomass Equations from Terrestrial LiDAR: A Case Study in Guyana Lau, A. Calders, K. Bartholomeus, H. Martius, C. Raumonen, P. Herold, M. Vicari, M. Sukhdeo, H. Singh, J. Goodman, R.C. biomass remote sensing allometry sampling Large uncertainties in tree and forest carbon estimates weaken national efforts to accurately estimate aboveground biomass (AGB) for their national monitoring, measurement, reporting and verification system. Allometric equations to estimate biomass have improved, but remain limited. They rely on destructive sampling; large trees are under-represented in the data used to create them; and they cannot always be applied to different regions. These factors lead to uncertainties and systematic errors in biomass estimations. We developed allometric models to estimate tree AGB in Guyana. These models were based on tree attributes (diameter, height, crown diameter) obtained from terrestrial laser scanning (TLS) point clouds from 72 tropical trees and wood density. We validated our methods and models with data from 26 additional destructively harvested trees. We found that our best TLS-derived allometric models included crown diameter, provided more accurate AGB estimates ( R 2 = 0.92–0.93) than traditional pantropical models ( R 2 = 0.85–0.89), and were especially accurate for large trees (diameter > 70 cm). The assessed pantropical models underestimated AGB by 4 to 13%. Nevertheless, one pantropical model (Chave et al. 2005 without height) consistently performed best among the pantropical models tested ( R 2 = 0.89) and predicted AGB accurately across all size classes—which but for this could not be known without destructive or TLS-derived validation data. Our methods also demonstrate that tree height is difficult to measure in situ, and the inclusion of height in allometric models consistently worsened AGB estimates. We determined that TLS-derived AGB estimates were unbiased. Our approach advances methods to be able to develop, test, and choose allometric models without the need to harvest trees. 2019-06-25 2021-03-08T08:19:40Z 2021-03-08T08:19:40Z Journal Article https://hdl.handle.net/10568/112152 en Open Access MDPI Lau, A., Calders, K., Bartholomeus, H., Martius, C., Raumonen, P., Herold, M., Vicari, M., Sukhdeo, H., Singh, J., Goodman, R.C. 2019. Tree Biomass Equations from Terrestrial LiDAR: A Case Study in Guyana. Forests, 10 (6) : 527. https://doi.org/10.3390/f10060527
spellingShingle biomass
remote sensing
allometry
sampling
Lau, A.
Calders, K.
Bartholomeus, H.
Martius, C.
Raumonen, P.
Herold, M.
Vicari, M.
Sukhdeo, H.
Singh, J.
Goodman, R.C.
Tree Biomass Equations from Terrestrial LiDAR: A Case Study in Guyana
title Tree Biomass Equations from Terrestrial LiDAR: A Case Study in Guyana
title_full Tree Biomass Equations from Terrestrial LiDAR: A Case Study in Guyana
title_fullStr Tree Biomass Equations from Terrestrial LiDAR: A Case Study in Guyana
title_full_unstemmed Tree Biomass Equations from Terrestrial LiDAR: A Case Study in Guyana
title_short Tree Biomass Equations from Terrestrial LiDAR: A Case Study in Guyana
title_sort tree biomass equations from terrestrial lidar a case study in guyana
topic biomass
remote sensing
allometry
sampling
url https://hdl.handle.net/10568/112152
work_keys_str_mv AT laua treebiomassequationsfromterrestriallidaracasestudyinguyana
AT caldersk treebiomassequationsfromterrestriallidaracasestudyinguyana
AT bartholomeush treebiomassequationsfromterrestriallidaracasestudyinguyana
AT martiusc treebiomassequationsfromterrestriallidaracasestudyinguyana
AT raumonenp treebiomassequationsfromterrestriallidaracasestudyinguyana
AT heroldm treebiomassequationsfromterrestriallidaracasestudyinguyana
AT vicarim treebiomassequationsfromterrestriallidaracasestudyinguyana
AT sukhdeoh treebiomassequationsfromterrestriallidaracasestudyinguyana
AT singhj treebiomassequationsfromterrestriallidaracasestudyinguyana
AT goodmanrc treebiomassequationsfromterrestriallidaracasestudyinguyana