Characteristics Of Fe, Mn And Zn Leached From Soils By Simulated Acid Rain

In this study, the releasing characteristics and mechanism of some metal ions from soils, which were collected of different mothers'rocks from Sichuan, were studied by simulated acid rain leaching of soil indoor. We analyzed not only the leaching characteristics of some heavy metals (Fe, Mn and Zn), but also the characteristics of pH on the leachate.Soil samples were soaked in simulated acid rain at different pH values (i.e., pH 1.0, 2.0, 3.0, 4.0, and 5.0), and distilled water for 24 h, and then the pH values and the concentrations of Fe, Mn and Zn of the leachate were determined by inductively coupled plasma–atomic emission spectrometry (ICP-AES). Analytical results showed that the release of these elements from the soil samples marinated by simulated acid rain was pH-dependent. The acid-tolerant abilities of different soil samples were different form each other, and this was probably originated from the chemical property of the elements, physical and chemical structure/properties of the soil samples and the pH values of the simulated acid rains. Under the condition of simulated acid rain, the content of ions of heavy metal increasd with the decrease of pH values of the simulated acid rain, while their increasing degree varied. When the pH values of the simulated acid rain was over 2.0, the total releasing amount of heavy metal ions in the soils increased rather small with the decrease of pH value;...