|
|
||||||||
a CSIRO Land and Water, Private Bag No. 2, Glen Osmond, Adelaide, SA 5064, Australia
b Department of Soil and Water, University of Adelaide, Waite Campus, Private Mail Bag No. 1, Glen Osmond, Adelaide, SA 5064, Australia
* Corresponding author (Ravi.Naidu{at}csiro.au)
Received for publication November 30, 1999. There are more than 10000 arsenic (As) contaminated sites in Australia. The ability of soils at these contaminated sites to sorb As is highly variable and appreciable amounts of As have been recorded in the subsurface soils. The potential risk of surface and ground water contamination by As at these sites is a major environmental concern. Factors that influence adsorption capacity of soils influence the bioavailability and subsequent mobility of As in soils. In the present study we investigated the effect of PO3-4 and Na+ and Ca2+ on the sorption of AsV and AsIII by an Oxisol, a Vertisol, and two Alfisols. The presence of P (0.16 mmol L-1) greatly decreased AsV sorption by soils containing low amounts of Fe oxides (<100 mmol kg-1), indicating competitive adsorption between P and AsV for sorption sites. In contrast, the presence of a similar amount of P had little effect on the amount of AsV adsorbed by soils with high Fe content (>800 mmol kg-1). However, AsV sorption substantially decreased from 0.63 to 0.37 mmol kg-1 as P concentration was increased from 0.16 to 3.2 mmol L-1 in selected soils. This suggests increased competition between P and AsV for soil sorption sites, through either the higher affinity or the effect of mass action of the increasing concentration of P in solution. A similar effect of P on AsIII sorption was observed in the low sorbing Alfisol and high affinity Oxisol. However, the amount of AsIII sorbed by the Oxisol was much greater than the Alfisol for all treatments. The presence of Ca2+ increased the amount of AsV sorbed compared with that of Na+ and was manifested through changes in the surface charge characteristics of the soils. A similar trend in AsIII sorption was recorded with changes in index cation, although the effect was not as marked as recorded for AsV.
This article has been cited by other articles:
![]() |
K. Szegedi, D. Vetterlein, H. Nietfeld, R. Jahn, and H.-U. Neue New Tool RhizoMath for Modeling Coupled Transport and Speciation in the Rhizosphere Vadose Zone J., May 27, 2008; 7(2): 712 - 720. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. P. Luxton, C. J. Tadanier, and M. J. Eick Mobilization of Arsenite by Competitive Interaction with Silicic Acid Soil Sci. Soc. Am. J., January 6, 2006; 70(1): 204 - 214. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Alvarez-Benedi, S. Bolado, I. Cancillo, C. Calvo, and D. Garcia-Sinovas Adsorption-Desorption of Arsenate in Three Spanish Soils Vadose Zone J., May 12, 2005; 4(2): 282 - 290. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. E. Wagner, F. J. Peryea, and R. A. Filby Antimony Impurity in Lead Arsenate Insecticide Enhances the Antimony Content of Old Orchard Soils J. Environ. Qual., March 1, 2003; 32(2): 736 - 738. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| The SCI Journals | Agronomy Journal | Crop Science | |||
| Vadose Zone Journal | Journal of Plant Registrations | ||||
| Journal of Natural Resources and Life Sciences Education |
Soil Science Society of America Journal |