Assessment of mobile and potential mobile trace elements extractability in calcareous soils using different extracting agents

• DTPA and NH₄OAc, HNO₃ and EDTA, and MgCl₂ and NH₄NO₃ had similar behavior. • In NH₄OAc, DTPA, and EDTA, the possibility of re-adsorption of trace elements is low. • CaCl₂ may be more suitable than other extracts in calcareous soils. Understanding trace elements mobility in soils, extracting agents, and their relationships with soil components, are essential for predicting their movement in soil profile and availability to plants. A laboratory study was conducted to evaluate extractability of cadmium (Cd), cobalt (Co), copper (Cu), nickel (Ni), and zinc (Zn) from calcareous soils utilizing various extracting agents to be specific CaCl₂, DTPA, EDTA, HNO₃, MgCl₂, NaNO₃, NH₄NO₃, and NH₄OAc. Cluster analysis indicated that DTPA and NH₄OAc, HNO₃ and EDTA, and MgCl₂ and NH₄NO₃ extracting agents yielded comparative values, whereas NaNO₃ and CaCl₂ have shown different behavior than other extracting agents for all studied trace elements. The speciation of extracted trace elements in solutions indicated that in the CaCl₂, NaNO₃, NH₄NO₃, and MgCl₂ extracting agents most extracted Cd, Co, Ni, Zn, and part of Cu were as free ions and may be re-adsorbed on soils, leading to lower extractability, whereas, in the case of HNO₃ extracting agent, the likelihood of re-adsorption of trace elements may be little. The results of speciation of trace elements using NH₄OAc, DTPA, and EDTA extracting agents showed that Me-(Acetate)₃^–, Me-(Acetate)₂(aq), Me(DTPA)³⁻, Me(EDTA)²⁻, and MeH(EDTA)^– complexes dominated in solutions indicating that the extracted trace elements may not be re-adsorbed on soils, leading to higher extractability. The results of this study are useful for short and long-term evaluations of trace elements mobility and further environmental impacts.     

Euphorbia leaf extract-assisted sustainable synthesis of Au NPs supported on exfoliated GO for superior activity on water purification: reduction of 4-NP and MB

Environmental Science and Pollution Research - In the present work, the effect of graphene oxide (GO) architecture and synthesis of gold nanoparticles (AuNPs) on the surface of GO by using...