Soil analytical results show that these HGUs represent different ASS physical and chemical properties in coastal sediments especially in the estuary zones of tidal shores and where river deposition occurs. The HGUs in the estuaries on the north coast have less disparity and pyrite concentration, despite their low energy environment, compared to the south coast. It was found that intensive aquaculture ponds and dredging activities were the main factors contributing to the absence of ASS in these estuaries. In contrast with some previous studies, in the south coast, the combination of high river and wave…