Analysis of Onshore and Offshore Soils in the Lower Xiangjiang River

Abstract

The soil on the west bank of the Xiangjiang River in the main urban area of Changsha, Hunan Province is referred to as shore soil, and the soil on the mid-levels of the Yuelu Mountains in Changsha is referred to as offshore soil. To stabilise the heavy metals in the soils, which do not readily migrate by pyrolysis, these soil samples were heated at 450°C for 3 hours in a muffle furnace and removed after natural cooling. These heated and stabilised soils were analysed by inductively coupled plasma emission spectrometry (ICP-OES), scanning electron microscopy (EMS) and XRD diffractometry respectively. It can be found that: (1) There is a difference in the heavy metal content between the shoreline soil and the offshore soil of the Xiangjiang River. (2) The scanning electron microscope shows that the microstructure of the soil is altered by prolonged river water infiltration and washing. (3) Both onshore and offshore soils are a mixture of crystalline and non-crystalline materials, with less non-crystalline material in the onshore soil compared to the offshore soil. (4) The main crystalline material in both onshore and offshore soils is SiO2.(5) Soil samples containing metallic elements are mostly in non-crystalline form.