Global application of an unoccupied aerial vehicle photogrammetry protocol for predicting aboveground biomass in non‐forest ecosystems

作者：Andrew M. Cunliffe, Karen Anderson, Fabio Boschetti, Richard E. Brazier, Hugh A. Graham, Isla H. Myers‐Smith, Thomas Astor, Matthias M. Boer, Leonor Calvo, Patrick E. Clark, Michael D. Cramer, M. Sebastián Encinas-Lara, S. M. Escarzaga, José Manuel Fernández‐Guisuraga, Adrian Fisher, Kateřina Gdulová, Breahna M. Gillespie, Anne Griebel, Niall P. Hanan, Muhammad S. Hanggito, Stefan Haselberger, Caroline A. Havrilla, Phil Heilman, Wenjie Ji, Jason W. Karl, Mario Kirchhoff, Sabine Kraushaar, Mitchell Lyons, Irene Marzolff, Marguerite Mauritz, C. David McIntire, Daniel Metzen, Luis A. Méndez‐Barroso, Simon C. Power, Jiří Prošek, Enoc Sanz‐Ablanedo, Katherine J. Sauer, Damian Schulze‐Brüninghoff, Petra Šímová, Stephen Sitch, Julian Smit, Caiti Steele, Susana Suárez‐Seoane, S. A. Vargas, Miguel L. Villarreal, Fleur Visser, M. Wachendorf, Hannes Wirnsberger, Robert Wojcikiewicz · 发表于：Remote Sensing in Ecology and Conservation · 年份：2021 · DOI：10.1002/rse2.228 · 被引用次数：51 · 研究领域：Remote Sensing and LiDAR Applications、3D Surveying and Cultural Heritage、Remote Sensing in Agriculture

Abstract Non‐forest ecosystems, dominated by shrubs, grasses and herbaceous plants, provide ecosystem services including carbon sequestration and forage for grazing, and are highly sensitive to climatic changes. Yet these ecosystems are poorly represented in remotely sensed biomass products and are undersampled by in situ monitoring. Current global change threats emphasize the need for new tools to capture biomass change in non‐forest ecosystems at appropriate scales. Here we developed and deployed a new protocol for photogrammetric height using unoccupied aerial vehicle (UAV) images to test its capability for delivering standardized measurements of biomass across a globally distributed field experiment. We assessed whether canopy height inferred from UAV photogrammetry allows the prediction of aboveground biomass (AGB) across low‐stature plant species by conducting 38 photogrammetric surveys over 741 harvested plots to sample 50 species. We found mean canopy height was strongly predictive of AGB across species, with a median adjusted R 2 of 0.87 (ranging from 0.46 to 0.99) and median prediction error from leave‐one‐out cross‐validation of 3.9%. Biomass per‐unit‐of‐height was similar within but different among, plant functional types. We found that photogrammetric reconstructions of canopy height were sensitive to wind speed but not sun elevation during surveys. We demonstrated that our photogrammetric approach produced generalizable measurements across growth forms and envir...