Research on the degradation of tropical arable land soil: Part III. The distribution of Cd in western part of Hainan Island

Research on arable land soil Cadmium (Cd) distribution is basic to Cd contamination control, especially in tropical areas with lower soil pH. This study, taking west Hainan as study area, collected soil samples from different soil horizons and demonstrated the distribution of Cd content. Soil Cd mainly inherits from the parent materials and the concentration of soil Cd is below 6 μg kg -1 . Generally, the content of Cd in Aa horizon is lower than the C horizon, but the higher variability of Aa horizon Cd concentration is more likely subject to outer source pollution. The soil parent material distribution is primary factor which may affect the spatial distribution of Cd in soil. The content of Cd is higher in the northern Andisol. In addition, the spatial analysis tool can be used to identify regions with significant different contents of elements in different horizons.