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Competitive sorption of heavy metal by soils. Isotherms and fractional factorial experiments
1998
Echevarria, Guillaume | Morera, M.T. | Mazkiaran, C. | Garrido, J.J. | Laboratoire Sols et Environnement (LSE) ; Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL) | Universidad Pública de Navarra [Espagne] = Public University of Navarra (UPNA)
Competing ions strongly affect heavy metal sorption onto the solid surfaces of soil. This study evaluated competitive sorption of Cd, Cu, Ni, Pb and Zn on three soils: Calcixerollic Xerochrept, Paralithic Xerorthent and Lithic Haplumbrept. Monometal and competitive sorption isotherms were obtained at 25°C. The individual effect of ions on retention of the others was ascertained by a fractional factorial analysis design. Most of the sorption isotherms belonged to type L subtype 2 in the classification of Giles. In competitive sorption the initial linear part was shorter and the knee sharper when compared with monometal sorption isotherms. Parameters related to sorptive capacity, such as Point B, Langmuir monolayer and Freundlich distribution coefficient, were higher in monometal than in competitive sorption, and in basic soils than in acidic soil. Calcium desorbed at different points of the sorption isotherms indicated that cationic exchange with Ca was the main retention mechanism in calcareous soils. For Pb, the ratio Ca desorbed/Pb sorbed was close to one; for Cu, Ni and Zn the ratio ranged from 1.20 to 1.37, probably due to partial dissolution of calcium carbonates by hydrolytic processes during retention. On the other hand, Cd had a ratio around 0.6 reflecting another additional retention mechanism, probably surface complexation. Fractional factorial design confirmed that the presence of the cations investigated reduced the amount of the five metals retained, but the presence of Cu and Pb in the system depressed Ni, Cd and Zn sorption more than the inverse. Cation mobility was enhanced when equilibrium concentration increased and the effect was higher in Ca-saturated soils.
Show more [+] Less [-]A comprehensive evaluation on the use of oxygen release compound in bioremediation [ORC]
1998
Koenigsberg, S.S.
The global nitrogen cycle: changes and consequences
1998
Galloway, J.N. (Department of Environmental Sciences, University of Virginia, Charlottesville, VA 22903 (USA))
Mixed farming systems as a way towards a more efficient use of nitrogen in European Union agriculture
1998
Oomen, G.J.M. | Lantinga, E.A. | Goewie, E.A. | Hoek, K.W. van der (Department of Plant and Crop Sciences, Group of Biological Farming Systems, Wageningen Agricultural University, Haarweg 333, 6709 RZ Wageningen (Netherlands))
Further studies of the air-pasture transfer of polychlorinated biphenyls
1998
Thomas, G.O. | Smith, K.E.C. | Sweetman, A.J. | Jones, K.C. (Environmental Science Department, Institute of Environmental and Natural Sciences, Lancaster University, Lancaster LA1 4YQ (United Kingdom))
Fate of airborne polychlorinated dibenzo-p-dioxins and dibenzofurans in an agricultural ecosystem
1998
Welsch-Pausch, K. | McLachlan, M.S. (Ecological Chemistry and Geochemistry, University of Bayreuth, 95440 Bayreuth (Germany))
The impact of land use on N2O emissions from watersheds draining into the Northeastern Atlantic Ocean and European Seas
1998
Kroeze, C. | Seitzinger, S.P. (WIMEK, Wageningen Agricultural University, Wageningen (Netherlands))
Air-soil exchange of semi-volatile organic compounds (SOCs) in the UK
1998
Cousins, I.T. | Jones, K.C. (Environmental Science Department, Institute of Environmental and Natural Sciences, Lancaster University, Lancaster LA1 4YQ (United Kingdom))
Chiral pesticides as tracers of air-surface exchange
1998
Bidleman, T.F. | Jantunen, L.M. | Harner, T. | Wiberg, K. | Wideman, J.L. | Brice, K. | Su, K. | Falconer, R.L. | Aigner, E.J. | Leone, A.D. | Ridal, J.J. | Kerman, B. | Finizio, A. | Alegria, H. | Parkhurst, W.J. | Szeto, S.Y. (Atmospheric Environment Service, 4905 Dufferin St, Downsview, Ontario, M3H 5T4 (Canada))
Nitrogen pollution on the local scale in Lithuania: vitality of forest ecosystems
1998
Armolaitis, K. (Department of Forest Soils, Typology and Hydrology, Lithuanian Forest Research Institute, LT-4312, Kaunas-Girionys (Lithuania))