Estimation of erosion- deposition trends across the Quang Nam coast in the background of the climate variability

Abstract

Relevance. In the face of current climate change trends, coastal erosion occurs more frequently in coastal lands. This problem not only causes damage to houses and works, but also affects the lives of coastal people. Quang Nam has a coastline of 125 km, which is an area that has been seriously eroded under the impact of hydrodynamic factors, along with extreme weather phenomena, affecting people's lives, and degrade the local economy. Aim. This article presents research on shoreline changes in Quang Nam region using the method of integrating remote sensing and GIS to create a change map. From there, identify erosion and deposition areas to help management agencies pay attention to the protection and development orientation of Quang Nam province in the context of climate change. Methods. Shoreline extraction method in combination with GIS to calculate the coastline change and combines with storm statistics to assess the shoreline change. Results. In the whole study area, erosion is dominant over deposition. Erosion is concentrated mainly in An Bang, North Cua Dai, Duy Hai and Tam Tien areas, ranging from 3.9–9.2 m/year. Deposition is concentrated mainly in the areas south of Cua Dai and Tam Hoa (near the mouth of Truong Giang river). In addition, the analysis results of shoreline changes in Quang Nam area, when combined with storm data affecting this area, also show a positive correlation. Research results can contribute useful information to local authorities to have solutions for planning and managing coastal areas.

Keywords

• shoreline extraction
• GIS
• erosion
• deposition
• Quang Nam
• MNDWI