Mobility of copper fertilizers in soils
Due to its cationic nature, Cu mobility is assumed to be very limited in Prairie soils, which are dominated by negatively charged constituents (McLaren et al., 1983). Clay and organic matter are major sources of these negatively charged surfaces. Root interception, therefore, plays an important role in plant uptake of Cu. Normally, where Cu fertilizer applications are required to correct a deficiency, proximity to growing roots is considered essential (Gilkes and Sadleir, 1979). Incorporation of surface broadcast copper sulphate (CuSO4) has been an effective practice. However, over the past decade, there has been a significant shift towards less tillage and an increased awareness of other products and methods of application. Chelating agents are added to nutrient solutions to increase the solubility of metal cations. Metal chelates are characterized by the formation of more than one bond between the metal and functional groups of the complexing agent, forming a ring structure incorporating the metal ion. One of the most common chelating agents used for this application is EDTA (ethylene diamine triacetic acid). The relatively high stability of this product in chemical reactions is seen as an advantage for maintaining the availability of the nutrient. The objective of this experiment was to identify the relative mobility of Cu, using two fertilizer products, namely, CuSO4 (salt) and Cu-EDTA (chelate).
The following license files are associated with this item: