ABSTRACT
Knowledge of interactions between trace elements in the soil–water environment is essential in assessing their bioavailability and potential toxicity in soils and wetlands. Trace elements include several heavy metals such as zinc, copper, arsenic, cadmium, and vanadium, among others. Several heavy metals such as Zn and copper are essential micronutrients that are required in the growth of both plants and animals. Micronutrients are often applied in the form of fertilizers or as supplements in animal feed. Heavy metals are extensively used as fungicides and as bactericides in numerous pharmaceuticals. The bioavailability of trace elements in the soil–water environment is dependent on an array of soil properties, including soil pH, organic matter content, amount and type of dominant clay, and carbonates, among others. In addition, the counterions present in the soil system greatly influence the fate of trace metals in soils. In fact, several studies suggested varied interactions of heavy metals with phosphates in soils as discussed in a later section.
