The Impact of Coal Exploitation on Tidal Flat Changes, an Investigation Using Remote Sensing Data in Vietnam

Abstract

Tidal flat plays a crucial role in socio-economic development and ecological environment.
Tidal flats in Ha Long-Cam Pha in Vietnam are impacted by human activities, especially coal mining
activities. Using remote sensing data is able to detect, extract, and monitor the changes of tidal flats and
exploited coal mine area with multi-temporal, in various scales, and for a large coverage. This study
aims to investigate the impact of coal mining activities on the changes of tidal flats using remote sensing
in Cam Pha, Ha Long, one of the biggest coal basins in Vietnam. Digital Elevation Models (DEMs) of
tidal flats constructed by Landsat satellite images acquired in years 1989, 2001, and 2014 are compared
to determine the volume changes. Besides, coal mining activities including coal production, waste rock
dump area, and the expansion of open coal mine during the period 1989-2014 are investigated using
correspondent Landsat images and the reports from the coal mine companies in the study area. Sediment
samples in tidal flats are analyzed to determine the origin of the sediments. As the results, organic matter
in the tidal flats is dominant with the concentration of 459 g/kg to 607 g/kg, which is evidence for the
impact of coal exploitation on the coastal environment. In addition, the relationship between coal mine
activities and tidal flat variation is well observed in this study.