Advanced search
1 file | 5.75 MB Add to list

Estimating urban above ground biomass with multi-scale LiDAR

Author
Organization
Abstract
Background: Urban trees have long been valued for providing ecosystem services (mitigation of the "heat island" effect, suppression of air pollution, etc.); more recently the potential of urban forests to store significant above ground biomass (AGB) has also be recognised. However, urban areas pose particular challenges when assessing AGB due to plasticity of tree form, high species diversity as well as heterogeneous and complex land cover. Remote sensing, in particular light detection and ranging (LiDAR), provide a unique opportunity to assess urban AGB by directly measuring tree structure. In this study, terrestrial LiDAR measurements were used to derive new allometry for the London Borough of Camden, that incorporates the wide range of tree structures typical of an urban setting. Using a wallto-wall airborne LiDAR dataset, individual trees were then identified across the Borough with a new individual tree detection (ITD) method. The new allometry was subsequently applied to the identified trees, generating a Boroughwide estimate of AGB. Results: Camden has an estimated median AGB density of 51.6 Mg ha(-1) where maximum AGB density is found in pockets of woodland; terrestrial LiDAR-derived AGB estimates suggest these areas are comparable to temperate and tropical forest. Multiple linear regression of terrestrial LiDAR-derived maximum height and projected crown area explained 93% of variance in tree volume, highlighting the utility of these metrics to characterise diverse tree structure. Locally derived allometry provided accurate estimates of tree volume whereas a Borough-wide allometry tended to overestimate AGB in woodland areas. The new ITD method successfully identified individual trees; however, AGB was underestimated by <= 25% when compared to terrestrial LiDAR, owing to the inability of ITD to resolve crown overlap. A Monte Carlo uncertainty analysis identified assigning wood density values as the largest source of uncertainty when estimating AGB. Conclusion: Over the coming century global populations are predicted to become increasingly urbanised, leading to an unprecedented expansion of urban land cover. Urban areas will become more important as carbon sinks and effective tools to assess carbon densities in these areas are therefore required. Using multi-scale LiDAR presents an opportunity to achieve this, providing a spatially explicit map of urban forest structure and AGB.
Keywords
cavelab, Above ground biomass, Urban forest, Airborne LiDAR, Terrestrial LiDAR, Allometry KeyWords Plus:ABOVEGROUND CARBON STORAGE, FOREST CARBON, TREE DETECTION, ALLOMETRIC RELATIONSHIPS, ECOSYSTEM SERVICES, SPATIAL-RESOLUTION, POINT DENSITY, LAND-USE, AIRBORNE, TERRESTRIAL

Downloads

  • 2018 Wilkes CBM.pdf
    • full text (Published version)
    • |
    • open access
    • |
    • PDF
    • |
    • 5.75 MB

Citation

Please use this url to cite or link to this publication:

MLA
Wilkes, Phil, et al. “Estimating Urban above Ground Biomass with Multi-Scale LiDAR.” CARBON BALANCE AND MANAGEMENT, vol. 13, 2018, doi:10.1186/s13021-018-0098-0.
APA
Wilkes, P., Disney, M., Vicari, M. B., Calders, K., & Burt, A. (2018). Estimating urban above ground biomass with multi-scale LiDAR. CARBON BALANCE AND MANAGEMENT, 13. https://doi.org/10.1186/s13021-018-0098-0
Chicago author-date
Wilkes, Phil, Mathias Disney, Matheus Boni Vicari, Kim Calders, and Andrew Burt. 2018. “Estimating Urban above Ground Biomass with Multi-Scale LiDAR.” CARBON BALANCE AND MANAGEMENT 13. https://doi.org/10.1186/s13021-018-0098-0.
Chicago author-date (all authors)
Wilkes, Phil, Mathias Disney, Matheus Boni Vicari, Kim Calders, and Andrew Burt. 2018. “Estimating Urban above Ground Biomass with Multi-Scale LiDAR.” CARBON BALANCE AND MANAGEMENT 13. doi:10.1186/s13021-018-0098-0.
Vancouver
1.
Wilkes P, Disney M, Vicari MB, Calders K, Burt A. Estimating urban above ground biomass with multi-scale LiDAR. CARBON BALANCE AND MANAGEMENT. 2018;13.
IEEE
[1]
P. Wilkes, M. Disney, M. B. Vicari, K. Calders, and A. Burt, “Estimating urban above ground biomass with multi-scale LiDAR,” CARBON BALANCE AND MANAGEMENT, vol. 13, 2018.
@article{8566924,
  abstract     = {Background: Urban trees have long been valued for providing ecosystem services (mitigation of the "heat island" effect, suppression of air pollution, etc.); more recently the potential of urban forests to store significant above ground biomass (AGB) has also be recognised. However, urban areas pose particular challenges when assessing AGB due to plasticity of tree form, high species diversity as well as heterogeneous and complex land cover. Remote sensing, in particular light detection and ranging (LiDAR), provide a unique opportunity to assess urban AGB by directly measuring tree structure. In this study, terrestrial LiDAR measurements were used to derive new allometry for the London Borough of Camden, that incorporates the wide range of tree structures typical of an urban setting. Using a wallto-wall airborne LiDAR dataset, individual trees were then identified across the Borough with a new individual tree detection (ITD) method. The new allometry was subsequently applied to the identified trees, generating a Boroughwide estimate of AGB.

Results: Camden has an estimated median AGB density of 51.6 Mg ha(-1) where maximum AGB density is found in pockets of woodland; terrestrial LiDAR-derived AGB estimates suggest these areas are comparable to temperate and tropical forest. Multiple linear regression of terrestrial LiDAR-derived maximum height and projected crown area explained 93% of variance in tree volume, highlighting the utility of these metrics to characterise diverse tree structure. Locally derived allometry provided accurate estimates of tree volume whereas a Borough-wide allometry tended to overestimate AGB in woodland areas. The new ITD method successfully identified individual trees; however, AGB was underestimated by <= 25% when compared to terrestrial LiDAR, owing to the inability of ITD to resolve crown overlap. A Monte Carlo uncertainty analysis identified assigning wood density values as the largest source of uncertainty when estimating AGB.

Conclusion: Over the coming century global populations are predicted to become increasingly urbanised, leading to an unprecedented expansion of urban land cover. Urban areas will become more important as carbon sinks and effective tools to assess carbon densities in these areas are therefore required. Using multi-scale LiDAR presents an opportunity to achieve this, providing a spatially explicit map of urban forest structure and AGB.},
  articleno    = {10},
  author       = {Wilkes, Phil and Disney, Mathias and Vicari, Matheus Boni and Calders, Kim and Burt, Andrew},
  issn         = {1750-0680},
  journal      = {CARBON BALANCE AND MANAGEMENT},
  keywords     = {cavelab,Above ground biomass,Urban forest,Airborne LiDAR,Terrestrial LiDAR,Allometry  KeyWords Plus:ABOVEGROUND CARBON STORAGE,FOREST CARBON,TREE DETECTION,ALLOMETRIC RELATIONSHIPS,ECOSYSTEM SERVICES,SPATIAL-RESOLUTION,POINT DENSITY,LAND-USE,AIRBORNE,TERRESTRIAL},
  language     = {eng},
  pages        = {20},
  title        = {Estimating urban above ground biomass with multi-scale LiDAR},
  url          = {http://dx.doi.org/10.1186/s13021-018-0098-0},
  volume       = {13},
  year         = {2018},
}

Altmetric
View in Altmetric
Web of Science
Times cited: