Title: | "Arsenic speciation dynamics in paddy rice soil-water environment: sources, physico-chemical, and biological factors - A review" |
Author(s): | Kumarathilaka P; Seneweera S; Meharg A; Bundschuh J; |
Address: | "School of Civil Engineering and Surveying, Faculty of Health, Engineering and Sciences, University of Southern Queensland, West Street, Toowoomba, Queensland, 4350, Australia. Center for Crop Health, Faculty of Health, Engineering and Sciences, University of Southern Queensland, West Street, Toowoomba, Queensland, 4350, Australia. Queen's University Belfast, Institute for Global Food Security, David Keir Building, Malone Road, Belfast, BT9 5BN, United Kingdom. School of Civil Engineering and Surveying, Faculty of Health, Engineering and Sciences, University of Southern Queensland, West Street, Toowoomba, Queensland, 4350, Australia; UNESCO Chair on Groundwater Arsenic within the 2030 Agenda for Sustainable Development, University of Southern Queensland, West Street, Toowoomba, Queensland, 4350, Australia. Electronic address: jochen.bundschuh@usq.edu.au" |
DOI: | 10.1016/j.watres.2018.04.034 |
ISSN/ISBN: | 1879-2448 (Electronic) 0043-1354 (Linking) |
Abstract: | "Rice is the main staple carbohydrate source for billions of people worldwide. Natural geogenic and anthropogenic sources has led to high arsenic (As) concentrations in rice grains. This is because As is highly bioavailable to rice roots under conditions in which rice is cultivated. A multifaceted and interdisciplinary understanding, both of short-term and long-term effects, are required to identify spatial and temporal changes in As contamination levels in paddy soil-water systems. During flooding, soil pore waters are elevated in inorganic As compared to dryland cultivation systems, as anaerobism results in poorly mobile As(V), being reduced to highly mobile As(III). The formation of iron (Fe) plaque on roots, availability of metal (hydro)oxides (Fe and Mn), organic matter, clay mineralogy and competing ions and compounds (PO(4)(3-) and Si(OH)(4)) are all known to influence As(V) and As(III) mobility in paddy soil-water environments. Microorganisms play a key role in As transformation through oxidation/reduction, and methylation/volatilization reactions, but transformation kinetics are poorly understood. Scientific-based optimization of all biogeochemical parameters may help to significantly reduce the bioavailability of inorganic As" |
Keywords: | Agriculture Arsenic/*analysis/chemistry/pharmacokinetics Biological Availability Biological Factors Ecosystem Floods Iron/analysis/metabolism *Oryza Plant Roots/chemistry Soil/chemistry Soil Pollutants/*analysis/chemistry/pharmacokinetics Spatio-Temporal; |
Notes: | "MedlineKumarathilaka, Prasanna Seneweera, Saman Meharg, Andrew Bundschuh, Jochen eng Review England 2018/05/19 Water Res. 2018 Sep 1; 140:403-414. doi: 10.1016/j.watres.2018.04.034. Epub 2018 Apr 21" |