The Contamination of Some Heavy Metals in Sediment and Influence of Organic Matter: Case study in Mangrove Forest Zone along the Coastal Area of Chanthaburi Province, the Eastern Gulf of Thailand

The determinations of zinc, copper, lead, cadmium, and organic matters (OM) in sediment along the coastal area of Chanthaburi Province, the Eastern Gulf of Thailand from 12 stations was conducted during the dry season (March 2021) and the wet season (September 2022). The quantity of heavy metals accumulated in sediment during the dry and wet season was Zn > Cu > Pb > Cd. The results showed that the average heavy metal concentration in the dry season was significantly higher than that in the wet season due to the low run off in the dry season resulting in increasing precipitation and accumulation processes. The results of the geoaccumulation index (I geo ) and enrichment factor (EF) values of the heavy metals content in the sediments indicated that the conservation area was unpolluted and not enriched, respectively.