@article{5fe7abf4719e405684161a37ea7b8398,
title = "A tree-based approach to biomass estimation from remote sensing data in a tropical agricultural landscape",
abstract = "Agricultural land now exceeds forests as the dominant global biome. Because of their global dominance, and potential expansion or loss, methods to estimate biomass and carbon in agricultural areas are necessary for monitoring global terrestrial carbon stocks and predicting carbon dynamics. Agricultural areas in the tropics have substantial tree cover and associated above ground biomass (AGB) and carbon. Active remote sensing data, such as airborne LiDAR (light detection and ranging), can provide accurate estimates of biomass stocks, but common plot-based methods may not be suitable for agricultural areas with dispersed and heterogeneous tree cover. The objectives of this research are to quantify AGB of a tropical agricultural landscape using a tree-based method that directly incorporates the size of individual trees, and to understand how landscape estimates of AGB from a tree-based method compare to estimates from a plot-based method. We use high-resolution (1.12 m) airborne LiDAR data collected on a 9280-ha region of the Azuero Peninsula of Panama. We model individual tree AGB with canopy dimensions from the LiDAR data. We apply the model to individual tree crown polygons and aggregate AGB estimates to compare with previously developed plot-based estimates. We find that agricultural trees are a distinct and dominant part of our study site. The tree-based approach estimates greater AGB in pixels with low forest cover than the plot-based approach, resulting a 2-fold difference in landscape AGB estimates between the methods for non-forested areas. Additionally, one third of the total landscape AGB exists in areas having <10% cover, based on a global tree cover product. Our study supports the continued use and development of allometric models to predict individual tree biomass from LiDAR-derived canopy dimensions and demonstrates the potential for spatial information from high-resolution data, such as relative isolation of canopies, to improve allometric models.",
keywords = "Agricultural carbon, Agroforestry, Allometric model, Land-sharing, LiDAR, Panama, Silvopasture, Trees on farms, Trees outside forests, Tropical trees",
author = "Graves, {Sarah J.} and Caughlin, {T. Trevor} and Asner, {Gregory P.} and Bohlman, {Stephanie A.}",
note = "Funding Information: The authors thank Diogenes Ibarra, Michelle Goodfellow, Lesely Candaleria, and Luis Mancilla, and members of the Azuero Earth Project, particularly Ruth Metzel and Jairo Batista-Bernal, for their support with field data collection. The remote sensing data collection, processing and analyses was supported by grants from the Grantham Foundation for the Protection of the Environment and William R. Hearst III. Funding for field data collection was provided by the Joshua C. Dickinson IV Fellowship and the Tinker Travel Fund through the University of Florida. The Carnegie Airborne Observatory has been made possible by the Avatar Alliance Foundation, Margaret A. Cargill Foundation, David and Lucile Packard Foundation, Gordon and Betty Moore Foundation, Grantham Foundation for the Protection of the Environment, W. M. Keck Foundation, John D. and Catherine T. MacArthur Foundation, Andrew Mellon Foundation, Mary Anne Nyburg Baker and G. Leonard Baker Jr, and William R. Hearst III. T. T. Caughlin was supported by National Science Foundation grant #1415297. Funding Information: The authors thank Diogenes Ibarra, Michelle Goodfellow, Lesely Candaleria, and Luis Mancilla, and members of the Azuero Earth Project, particularly Ruth Metzel and Jairo Batista-Bernal, for their support with field data collection. The remote sensing data collection, processing and analyses was supported by grants from the Grantham Foundation for the Protection of the Environment and William R. Hearst III. Funding for field data collection was provided by the Joshua C. Dickinson IV Fellowship and the Tinker Travel Fund through the University of Florida. The Carnegie Airborne Observatory has been made possible by the Avatar Alliance Foundation, Margaret A. Cargill Foundation, David and Lucile Packard Foundation, Gordon and Betty Moore Foundation, Grantham Foundation for the Protection of the Environment, W. M. Keck Foundation, John D. and Catherine T. MacArthur Foundation, Andrew Mellon Foundation, Mary Anne Nyburg Baker and G. Leonard Baker Jr, and William R. Hearst III. T. T. Caughlin was supported by National Science Foundation grant # 1415297 . Publisher Copyright: {\textcopyright} 2018 Copyright: Copyright 2018 Elsevier B.V., All rights reserved.",
year = "2018",
month = dec,
day = "1",
doi = "10.1016/j.rse.2018.09.009",
language = "English (US)",
volume = "218",
pages = "32--43",
journal = "Remote Sensing of Environment",
issn = "0034-4257",
publisher = "Elsevier Inc.",
}