Influence of Coastal Land Use on Soil Heavy-Metal Contamination in Pattani Bay, Thailand

Abstract

Abstract Expansion of land use in coastal areas results in natural resources being degraded, particularly by soil and water pollution. The objectives of this study were to assess land-use patterns and determine the influence of land-use types on soil heavy-metal contamination in Pattani Bay, Thailand. In studying land use, high-resolution SPOT satellite images were used and analyzed using ArcView GIS 3.2a and ENVI 3.5 software. Collections from 16 soil-sampling sites with topsoil and subsoil layers (0–20 and 21–50 cm in depth) from nine land-use types were carried out during March and April 2006. The heavy metals mercury, lead (Pb), cadmium, arsenic (As), and zinc were analyzed using a Perkin Elmer Optima 2100 DV. Results found that land uses in 2006 were mainly dominated by agricultural, residential, and mangrove-forest areas. In agricultural areas, paddy field were the main land use, followed by shrimp farms. In residential areas, most land was used for living, infrastructure, and industry. Land-use typ...