Examining the applicability of UAV-based photogrammetry to assess sediment yield from small fire-affected forests

Lee, J., Im. S., Kim, T.

Examining the applicability of UAV-based photogrammetry to assess sediment yield from small fire-affected forests

XV World Forestry Congress, 2-6 May 2022

Year of publication 2022

Place of publication Rome, Italy ;

Pages 1p.

Author Lee, J., Im. S., Kim, T.

Publisher FAO ;

Product type Document

Full item page

Synopsis (short abstract) Forest clearance after a fire is commonly implemented in fire-affected forests in South Korea, removing damaged vegetation and ash-litter layers. It undoubtedly affects hydrological processes, thereby leads to severe soil erosion to the downstream waterbodies such as stream, reservoir, dam. Therefore, accurate understanding of the magnitude of sediment yields is a prerequisite to implement the sediment control measures in the fire-affected region. Over the past decades, direct field measurement of sediment yields has been conducted over the world, particularly in South Korea. The traditional field survey has restricted to the application due to requiring a lot of labor and time and is only used to small and limited area. In this study, we tried to overcome the limitations of traditional approach by monitoring the sediment yield variations through images obtained from UAVs. For this purpose, direct field survey and UAV image-based photogrammetry were conducted on erosion control dams located in the downstream of mountain terrain. A comparison of sediment deposition in the dams were done to assess the applicability and reliability of UAV photogrammetry in forest sectors. The results show that UAV-derived photogrammetry technique can be considered as the alternative of field surveying when estimates the relief and terrain shape in a site where direct access and available resource are limited. This study may introduce a simple and accurate methodology for measuring soil loss and sediment yield on degraded mountain areas. Keywords: Monitoring and data collection ID: 3623072

Statutory body / Meeting title World Forestry Congress (WFC)

Language English

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