Evaluation of coastal erosion by using Landsat data in Ca Mau Cape, Ngoc Hien District, Ca Mau Province

Abstract

Coastal erosion as well as loss of aquaculture, cultivated and residential lands are of great concern in the Mekong Delta, especially in the Ca Mau Cape region. Historical map data and remote sensing images such as Landsat data combined with GPS field surveys are the optimal methods for assessing shoreline changes including coastal erosion and sedimentation. The 57-year coastline change during the period from 1965 to 2022 has been described through the processing of topographic map data published in 1965 and a series of Landsat-1 to Landsat-8 images collected in 1973, 1993, 2003, and 2022. The study found that the northeast of the study area in Cho Thu hamlet, Tam Giang Tay commune was the place where the largest erosion reached an annual average of 42.4 m/year. Due to the development program of afforestation, largest sediment reaches an annual average of 88.7 m/year in Ca Mau Cape National Park in Lach Vam hamlet, Dat Mui commune. However, during the 57-year period, coastal erosion has caused a loss of 1,714 hectares of land or 2.60% of the total area. Results from this work also suggest that the accuracy of the shoreline studies should be improved by using higher satellite data spatial resolution and the GPS system with dual frequencies for Real-time Kinematics (RTK) for coordinate positioning measurement.