Assessing Mangrove Above-Ground Biomass and Structure using Terrestrial Laser Scanning: A Case Study in the Everglades National Park

Mangroves are among the ecosystems with the highest potential for carbon sequestration and storage. In these ecosystems and others above-ground biomass (AGB) is often used to estimate above-ground carbon content. We used a Leica-ScanStation-C10 Terrestrial Laser Scanner (TLS) to estimate the volume and AGB of 40 mangrove trees distributed in three different mangrove sites located along Shark River Slough (SRS), in the western Everglades National Park. To estimate the volumetric shape of mangroves, we modeled stems as tapered geometrical surfaces called frustums of paraboloids and prop roots (Rhizophora mangle) as toroids and cylinders. AGB was estimated by multiplying the TLS-derived volume by wood specific density. Our TLS method for the SRS sites resulted in AGB estimates in the range of: 3.9 +/- 0.4 to 31.3 +/- 3.4 kg per tree in the short mangrove (< 5 m) site, 27.4 +/- 3.0 to 119.1 +/- 12.9 kg per tree in the intermediate (< 13 m) site and 52.1 +/- 6.7 to 1756.5 +/- 189.7 kg per tree in the tall (13-23 m) mangrove site. Our quantitative results: (1) enabled us to develop site-specific allometric relationships for tree diameter and AGB and (2) suggested that TLS is a promising alternative to destructive sampling.