Single-Pass UAV-Borne GatorEye LiDAR Sampling as a Rapid Assessment Method for Surveying Forest Structure

Author(s):Show less -

Prata, Gabriel Atticciati ^[1] ; Broadbent, Eben North ^[1] ; Alves de Almeida, Danilo Roberti ^{[2, 1]} ; St Peter, Joseph ^[3] ; Drake, Jason ^{[3, 4]} ; Medley, Paul ^{[3, 4]} ; Dalla Corte, Ana Paula ^{[1, 5]} ; Vogel, Jason ^[6] ; Sharma, Ajay ^[7] ; Silva, Carlos Alberto ^{[6, 8]} ; Zambrano, Angelica Maria Almeyda ^[9] ; Valbuena, Ruben ^[10] ; Wilkinson, Ben ^[11]

Affiliation:Show less -

^[1] Univ Florida, Sch Forest Resources & Conservat, Spatial Ecol & Conservat SPEC Lab, Gainesville, FL 32611 - USA

^[2] Univ Sao Paulo USP ESALQ, Luiz de Queiroz Coll Agr, Dept Forest Sci, BR-13418900 Piracicaba, SP - Brazil

^[3] Florida A&M Univ, Sch Environm, CSER, Tallahassee, FL 32307 - USA

^[4] US Forest Serv, USDA, Natl Forests Florida, Tallahassee, FL 32303 - USA

^[5] Fed Univ Parana UFPR, Dept Forest Engn, BR-80060000 Curitiba, Parana - Brazil

^[6] Univ Florida, Sch Forest Resources & Conservat, Gainesville, FL 32611 - USA

^[7] Univ Florida, West Florida Res & Educ Ctr, Milton, FL 32583 - USA

^[8] Univ Maryland, Dept Geog Sci, College Pk, MD 20740 - USA

^[9] Univ Florida, Ctr Latin Amer Studies, Spatial Ecol & Conservat SPEC Lab, Gainesville, FL 32611 - USA

^[10] Bangor Univ, Sch Nat Sci, Bangor LL57 2UW, Gwynedd - Wales

^[11] Univ Florida, Sch Forest Resources & Conservat, Geomat Program, Gainesville, FL 32611 - USA

• Document type: Journal article
• Source: REMOTE SENSING; v. 12, n. 24 DEC 2020.
• Web of Science Citations: 2

Abstract

Unmanned aerial vehicles (UAV) allow efficient acquisition of forest data at very high resolution at relatively low cost, making it useful for multi-temporal assessment of detailed tree crowns and forest structure. Single-pass flight plans provide rapid surveys for key selected high-priority areas, but their accuracy is still unexplored. We compared aircraft-borne LiDAR with GatorEye UAV-borne LiDAR in the Apalachicola National Forest, USA. The single-pass approach produced digital terrain models (DTMs), with less than 1 m differences compared to the aircraft-derived DTM within a 145 degrees field of view (FOV). Canopy height models (CHM) provided reliable information from the top layer of the forest, allowing reliable treetop detection up to wide angles; however, underestimations of tree heights were detected at 175 m from the flightline, with an error of 2.57 +/- 1.57. Crown segmentation was reliable only within a 60 degrees FOV, from which the shadowing effect made it unviable. Reasonable quality threshold values for LiDAR products were: 195 m (145 degrees FOV) for DTMs, 95 m (110 degrees FOV) for CHM, 160 to 180 m (similar to 140 degrees FOV) for ITD and tree heights, and 40 to 60 m (similar to 60 degrees FOV) for crown delineation. These findings also support the definition of mission parameters for standard grid-based flight plans under similar forest types and flight parameters. (AU)

• FAPESP's process: 18/21338-3 - Monitoring forest landscape restoration from unmanned aerial vehicles using Lidar and hyperspectral remote sensing
• Grantee: Danilo Roberti Alves de Almeida
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 19/14697-0 - Monitoring the demography and diversity of forests undergoing restoration using a drone-lidar-hyperspectral system
• Grantee: Danilo Roberti Alves de Almeida
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor