The behavior of heavy metals in soil

Abstract

This work takes as an object to explore, by means of a bibliographical review, some factors that affect the mobility of heavy metals in the soil. According to the relevant literature one finds that factors that have significant influence on the chemical behavior of heavy metals as Pb, Cd, Ni, Cu, and Cr in the soil are the pH of the soil, the organic matter, the content and type of clay, the oxides of Fe, Mn and Al, the carbonates, and the redox potential of the soil. The higher pH increases the number of available adsorption places in the minerals of clays, in the amorphous oxides and the organic matter, but not necessarily increases the quantity of adsorbed trace-metal. In minerals and clay, the capacity of linkage of the metals has direct bearing on capacity of cationic exchange (CEC), the greater adsorbed. Another element to stand out is the big affinity of elements as Co, Cd, Cu, Fe, Mn, Ni, Pb, U, and Zn for carbonates. There are numerous related to analysis the adsorption of the metals weighed in the soil and their relation to their bioavailability for the plants, they have concluded that these processes are highly influenced by the presence of organic matter