Determination of Available Iron Species in Soil by Differential Pulse Voltammetry

The available metal species are significant for the growth and development of plants. Thus, it is important to detect the content of available metal species in soil at real-time. Available iron in soil used to be determined by atomic absorption spectrometry or inductive coupled plasma emission spectrometer (ICP) method, which is quite expensive and not easy to operate, especially for farmers. This paper reports a rapid electrochemical method only by applying an electrochemical workstation equipment. Compared to stripping voltammetry method, differential pulse voltammetry (DPV) in this work can detect the available iron species accurately just by directly using the soil extraction solution and does not need the acidic digestion procedure. The DPV strategy we adopted in this work has the advantages of convenience, rapidity and high precision, and can reach the measurement level of ICP method. The content of available iron in soil is accurately determined by electrochemical technique (differential pulse voltammetry) using DTPA-TEA-CaCl2 soil extraction solution directly without acidic digestion treatment. This strategy displays the advantages of convenience, rapidity and high precision, which reaches the measurement level of ICP method.image