Estimating Mangrove Forest Volume Using Terrestrial Laser Scanning and UAV-Derived Structure-from-Motion

Abstract

Mangroves provide a variety of ecosystem services, which can be related to their structuralcomplexity and ability to store carbon in the above ground biomass (AGB). Quantifying AGB inmangroves has traditionally been conducted using destructive, time-consuming, and costlymethods, however, Structure-from-Motion Multi-View Stereo (SfM-MVS) combined withunmanned aerial vehicle (UAV) imagery may provide an alternative. Here, we compared the abilityof SfM-MVS with terrestrial laser scanning (TLS) to capture forest structure and volume in threemangrove sites of differing stand age and species composition. We describe forest structure in termsof point density, while forest volume is estimated as a proxy for AGB using the surface differencingmethod. In general, SfM-MVS poorly captured mangrove forest structure, but was efficient incapturing the canopy height for volume estimations. The differences in volume estimations betweenTLS and SfM-MVS were higher in the juvenile age site (42.95%) than the mixed (28.23%) or mature(12.72%) age sites, with a higher stem density affecting point capture in both methods. These resultscan be used to inform non-destructive, cost-effective, and timely assessments of forest structure orAGB in mangroves in the future.

A Study on Obtaining Tree Data from Green Spaces in Parks Using Unmanned Aerial Vehicle Images: Focusing on Mureung Park in Chuncheon

“…The lower layers are mostly shrubs, and thus there were limitations in calculating the volume with UAV images filmed in this study. Warfield et al (2019) proved that the 3D green structure that can be estimated by UAVs can be overestimated or underestimated depending on the space that has different structural characteristics (areas with high density or low density) and argued that there is a need for methods to overcome the limitations in order to more accurately estimate the 3D green structure. Therefore, to measure accurate areas and volumes of green spaces in parks using UAVs, it is necessary to film even the lower parts of trees in addition to using images that can be filmed above ground.…”

Unoccupied Aircraft Systems (UAS) for Marine Ecosystem Restoration

“…The development of structural metrics in vegetated environments has been greatly enhanced by the addition of UAS tools. Multiple studies have used SfM products to measure canopy heights and estimate biomass in mangroves (Warfield and Leon, 2019;Yaney-Keller et al, 2019). Yaney-Keller et al 2019actually used a dual band NDVI sensor (no RGB) in conjunction with SfM to measure canopy heights and percent cover in mangroves, and differentiate species in the estuaries of Pacific Costa Rica.…”

Karakteristik Mangrove Di Muara Sungai Timur Kawasan Laguna Segara Anakan, Kabupaten Cilacap Jawa Tengah

“…Ekosistem mangrove memiliki fungsi sebagai tempat hidup, berkembang biak bagi bota laut, dan dapat melindungi pemukiman dari angin kencang (Warfield & Leon, 2019;Noor et al, 2006). Struktur komunitas mangrove merupakan parameter dalam menentukan kondisi mangrove di suatu kawasan.…”