Application of unmanned aerial vehicle to estimate seagrass biomass in Kung Kraben Bay, Chanthaburi province, Thailand

Abstract

The seagrass beds are a unique marine productive ecosystem that provides a shelter, a food source for the marine community of animals and act as a biofilter in marine environments. An aerial photograph was reported by applying the Unmanned Aerial Vehicle (UAV). It was classified as seagrass beds in the Kung Kraben Bay. The study area covered 5.59 km2, which was shallow (depth 2.5 meters) and clear water in the Tha Mai district, Chanthaburi province, Thailand. The visual interpretation with field survey data assisted to classified in 3 classes such as a long seagrass leaves type (Enhalus acoroides), short seagrass leaves type (Halodule pinifolia and Halodule uninervis), and another object. The classification results showed that visual interpretation with the field survey data that was the overall accuracies and Kappa coefficients such as 74.42% and 0.568, respectively. The estimated biomasses of (i) E. acoroides and (ii) H. pinifolia and H. uninervis were 361.89 and 53.83 grams dry weight per square meter, respectively. The average biomass of seagrass zone showed that (i) E. acoroides was 454.24 Ton and (ii) H. pinifolia and H. uninervis were 54.28 Ton in 2017.