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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 [-]Structural-functional rearrangements in chromosome G in Chironomus riparius (Diptera, Chironomidae) collected from a heavy metal-polluted area near Turin, Italy
1998
Michailova, P. | Petrova, N. | Sella, G. | Ramella, L. | Bovero, S. (Institute of Zoology, Bulgarian Academy of Sciences, 1 Tzar Osvoboditel boulv. Sofia 1000, Bulgaria)
Heavy metal concentrations in consecutive saturation extracts of dredged sediment derived surface soils
1998
Tack, F.M.G. | Singh, S.P. | Verloo, M.G. (Laboratory for Analytical Chemistry and Applied Ecochemistry, University of Ghent, Coupure Links 653, B-9000 Gent (Belgium))
Competitive sorption of heavy metal by soils. Isotherms and fractional factorial experiments
1998
Echeverria, J.C. | Morera, M.T. | Mazkiaran, C. | Garrido, J.J. (Universidad Publica de Navarra, Departamento de Quimica Aplicada, Campus Arrosadia, 31006 Pamplona (Spain))
Evaluation of heavy metal lability in polluted soils by a cation exchange batch procedure
1998
Esnaola, M.V. | Millan, E. (Departamento de Quimica Aplicada Facultad de Quimica, Universidad del Pais Vasco, Apdo. 1072, 20080 San Sebastian (Spain))
Experience with the replication of regional survey of soil pollution
1998
Meuli, R. | Schulin, R. | Webster, R. (ETH Zurich, Institute for Terrestrial Ecology, Grabenstrasse 3, 8952 Schlieren (Switzerland))
Changes in tree ring chemistry in sugar maple (Acer saccharum) along an urban-rural gradient in southern Ontario
1998
Watmough, S.A. | Hutchinson, T.C. | Sager, E.P.S. (Environmental Resource Studies Program, Trent University, Peterborough, Ontario, K9J 7B8 (Canada))
The manure model: manure, minerals (N, P and K), ammonia emission, heavy metals and the use of fertiliser in Dutch agriculture
1998
Oudendag, D.A. | Luesink, H.H. (Agricultural Economics Research Institute [LEI-DLO], The Hague (Netherlands))
Assessment of Atmospheric Heavy Metals by Moss Monitoring with Isothecium Stoloniferum Brid. in the Fraser Valley, B.C., Canada
1998
Pott, Ute | Turpin, David H.
The atmospheric heavy metal pollution of the Fraser Valley, B.C., Canada was assessed in 1993 by analyzing 62 samples of the common woodland moss Isothecium stoloniferum for lead, cadmium, nickel, zinc, chromium, and manganese. The latter two metals did not show a distinct regional distribution, but lead, cadmium, nickel, and zinc showed distinct pattern along a west-east gradient. High values were found in the metropolitan Vancouver area, located in the west of the study region. Significantly lower values were recorded for mosses from the eastern more rural areas of the Fraser Valley. Metal pollutants are likely to be contained close to their emission sources by alternating south-east, north-west winds. Highest values overall were found in the North Shore Mountains, adjacent to Vancouver. This was related to higher precipitation and short range pollutant transport from the industrialized, heavily populated areas in the floodplain of the Fraser River.
Show more [+] Less [-]Comparisons and temporal trends of organochlorines and heavy metals in fish from the Gulf of Bothnia
1998
Vuorinen, P.J. | Haahti, H. | Leivuori, M. | Miettinen, V. (Finnish Game and Fisheries Research Institute, P.O. Box 6, FIN-00721, Helsinki (Finland))