ABSTRACT
Most freshwaters receive a plentiful supply of iron, as it is one of the most abundant elements in the earth’s crust. The basic biological and chemical interactions of iron in freshwaters have been known for many years. This chapter concerned with the formation, characteristics, and role of iron particles in freshwaters. It examines developments in the context of the firm foundations of the past and shows how understanding of iron particles and their interactions is at the forefront of developments in aquatic science. Iron occurs in a wide variety of rocks, as a major component of discrete minerals such as pyrite, FeS2, as a substitution element in alumino-silicates, and as a minor constituent of sedimentary rocks such as sandstone and limestone. Wherever the redox boundary resides within a freshwater system, similar processes govern the transport of iron and its oxidation and reduction. A generalized conceptual model for the transport of iron at a redox boundary has been proposed.
