Arsenic behaviour in soil-plant system: Biogeochemical reactions and chemical speciation influences

Abstract

Arsenic (As) is classified as a Class A human carcinogen and has gained a substantial attention in recent years owing to its high levels currently observed in the environment and adverse impacts on human health. Several studies have delineated the biogeochemical behaviour of As in soil-plant system in relation to its chemical speciation and bioavailability. This chapter establishes a link between As speciation and biogeochemical behaviour of As in complex soil-plant systems. It gives an overview of different biogeochemical processes that govern environmental behaviour of As in soil-plant system; highlights how the chemical speciation of As affects its biogeochemical behaviour (adsorption/desorption, mobility, bioavailability/ phytoavailability) in soil-plant system; and discusses relationship of soil physico-chemical properties (pH, clay contents, biological and microbial conditions, presence of organic and inorganic ligands and competing anions/cations) with chemical speciation of As as well as its biogeochemical behaviour in soil-plant system.