Survival Rate Assessment of Transplanted Seagrass Using Unmanned Aerial Vehicles Imagery on Google Earth Engine
Abstract
Department of Marine and Coastal Resources (DMCR) together with local communities around Phangnga bay have restored 0.1536 square kilometer of Enhalus acoroides (Linnaeus f.) Royle, 1839. Total of 153,600 shoots and sprout has been transplanted to the site since 2018 to 2021. The survival rate of the seagrass was assessed by in-situ visual investigation which was time-consuming, labor-intensive and cover only small portion of the restoration area. This paper presents a faster and better area coverage assessment procedure using Unmanned Aerial Vehicle (UAV) imagery analyzed on Google Earth Engine platform. The result of survival rate assessed by this method is 31.62 ±4.52 percent on average with mean accuracy detection (0.85 ±0.05) under specific condition such as sea level and seagrass density which negatively affect the detection efficiency. The proposed model output can be implemented to assess the accomplishment of DMCR seagrass restoration project.References
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