Characteristics of Cu Adsorption/Desorption of Vegetable Garden Soils

An experiment was carried out to study Cu adsorption/desorption of three vegetable garden soils with results showing that Cu²⁺ adsorption increased with Cu²⁺concentration in the equilibrium solutions of the three soils. This fitted quite well with both Langmuir equation and Freundlich equation. The maximum Cu²⁺ adsorption and maximum buffering capacity of the soils obtained from Langmuir equation was in such a decreasing order as Fluvio marine yellow loamy soil (Huang Song Tu)>Fluvio marine polder soil (Jiang Tu Tu)>Aquic silt loamy soil (Fen Ni Tu).Cu²⁺ desorption and Cu\+\2+\ desorption rate of the soils increased with Cu²⁺ adsorption of the soils. Significant or extremely significant positive linear relationship was observed between their adsorption and desorption.