Trace elements of the soil-plant systems in subtropical karst and clasolite areas in Guilin, Guangxi, China

The transfer processes of trace elements within the soil-plant system is part of the biochemical cycling of chemical elements-representing a flow of elements from nonliving to living compartments in biosphere. Trace elements distribution in soil-plant system is a key issue in assessing their mobility and availability in soils. This study was conducted to assess the transfer mechanism of copper (Cu), iron (Fe), manganese (Mn), nickel (Ni), strontium (Sr) and zinc (Zn) in eleven natural plants and associated rhizosphere soils in subtropical karst and clasolite areas, Southwestern China, using inductively coupled plasma-atomic emission spectroscopy. Trace elements except Sr are rich in the limestone soil of the karst area, whereas they are dispersed in the red soil of the clasolite area. Moreover, their active rates in the limestone soil are greatly reduced, compared with the red soil. Contents of trace elements in plants are both affected by the geochemical and biogeochemical characteristics of trace elements. Distributions of trace elements are related to plants' physiological characteristics, trace elements' chemical characteristics, and geological background as well.