Abstract
We modified a five-step sequential extraction scheme originally developed for phosphorus (P) in lake and marine sediments for use in a Danish freshwater wetland rich in organic matter. In contrast to the original scheme, the modification suggests isolation of P associated with aluminum (Al) and iron (Fe) in humic acid complexes. As in the original scheme, discrimination also was obtained between inorganic P associated with reducible forms of Fe and inorganic P associated with Al oxides. This is important because only iron-bound P is likely to be mobilized when wetland sediments become anoxic. Extraction of ironbound P was performed by use of bicarbonate-buffered dithionite and was followed by a NaOH treatment that extracted most organic bound P together with P adsorbed onto clays and Al oxides. The NaOH extract was dark brown, but upon acidification (pH≈1), we produced a precipitate of presumeably humic acids (HA) and a clear supernatant. The precipitate contained up to 30% of the total sediment P and significant fractions of sediment Al and Fe. Ratios of ∼ 12 between HA-Al and HA-P and of ∼ 2.5 between HA-Fe and HA-P suggest that most HA-P was associated with Al in the humic acid complexes. Comparison with sediment from an acid-bog lake suggests that the HA-P fraction might also be important in other freshwater sediments. A similar Al:P and Fe:P ratio was found in the humic acid precipitate from the lake sediment, indicating that the same mechanism was responsible for binding inorganic P in the humic acid complex as in the wetland sediment. When wet sediments were sieved through a 2-mm mesh and handled under N2, the method was highly reproducible, and no further precision could be obtained by grinding the wet sediment prior to extraction.
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Literature Cited
Andersen, J. M.. 1976. An ignition method for determination of total phosphorus in lake sediments. Water Research 10:329–331.
Barbanti, A., M. C. Bergamini, F. Frascari, S. Miserocchi and G. Rosso. 1994. Critical aspects of sedimentary phosphorus chemical fractionation. Journal of Environmental Quality 23:1093–1102.
Bloom, P. R. 1981. Phosphorus adsorption by an aluminum-peat complex. Soil Science Society of America Journal 45:267–272.
Blume, H. P. and U. Schwertmann. 1969. Genetic evaluation of profile distribution of Aluminum, Iron, and Manganese oxides. Soil Science Society of America Proceedings 33:438–444.
Bowman, R. A. and C. V. Cole. 1978. An exploratory method for fractionation of organic phosphorus from grassland soils. Soil Science 125:95–101.
Bremner, J. M. and C. S. Mulvaney. 1982. Nitrogen-total. p. 595–624.In A. L. Page, R.H. Miller, and D.R. Keeney (eds.) Methods of Soil Analysis. Part 2-Chemical and Microbiological Properties. Agronomy 9. American Society of Agronomy, Inc. Soil Science Society of America, Inc., Madison, WI, USA.
Chambers, R. M. and W. E. Odum. 1990. Porewater oxidation, dissolved phosphate and the iron curtain. Biogeochemistry 10:37–52.
Chang, S. C. and M. L. Jackson. 1957. Fractionation of soil phosphorus. Soil Science 84:133–144.
Cooke, J. G., L. Stub and N. Mora. 1992. Fractionation of phosphorus in the sediment of a wetland after a decade receiving sewage effluent. Journal of Environmental Quality 21:726–732.
De Groot, C. J. and H. L. Golterman. 1993. On the presence of organic phosphate in some Camargue sediments: evidence for the importance of phytate. Hydrobiologia 252:117–126.
Franco, D. A. 1986. Epilimnitic phosphorus cycling: influence of humic materials and iron on coexisting major mechanisms. Canadian Journal of Fisheries and Aquatic Sciences 43:302–310.
Gerke, J. 1992. Phosphate, aluminium and iron in the soil solution of three different soils in relation to varying concentrations of citric acid. Zeitschrift fur Pflanzenernahrung und Bodenkunde 155:339–343.
Gerke, J. and R. Hermann. 1992. Adsorption of orthophosphate to humic-Fe-complexes and to amorphous Fe-oxide. Zeitschrift fur Pflanzenernahrung und Bodenkunde 155:233–236.
Gerke, J. and A. Jungk. 1991. Separation of phosphorus bound to organic matrices from inorganic phosphorus in alkaline soil extracts by ultrafiltration. Communications in Soil Science and Plant Analysis 22:1621–1630.
Hartikainen, H. 1979. Phosphorus and its reactions in terrestrial soils and lake sediments. Journal of the Scientific Agricultural Society of Finland 51:537–624.
Haynes, R. J. and R. S. Swift. 1989. The effects of pH and drying on adsorption of phosphate by aluminium-organic matter associations. Journal of Soil Science 40:773–781.
Hieltjes, A. H. M. and L. Lijklema. 1980. Fractionation of inorganic phosphates in calcareous sediments. Journal of Environmental Quality 9:405–407.
Jensen, H. S. and B. Thamdrup. 1993. Iron-bound phosphorus in marine sediments as measured by bicarbonate-dithionite extraction. Hydrobiologia 253:47–59.
Jones, R. I., P. J. Shaw and H. D. Haan. 1993. Effects of dissolved humic substances on the speciation of iron and phosphate at different pH and ionic strength. Environmental Science and Technology 27:1052–1059.
Koch, M. S. and K. R. Reddy. 1992. Distribution of soil and plant nutrients along a trophic gradient in the Florida Everglades. Soil Science Society of America Journal 56:1492–1499.
Koenings, J. P. and E. E. Hooper. 1976. The influence of colloidal organic matter on iron and iron-phosphorus cycling in a bog lake. Limnology and Oceanography 21:684–696.
Kodama, H. and M. Schnitzer. 1977. Effect of fulvic acid on the crystallization of Fe(III) oxides. Geoderma 19:279–291.
Koroleff, F. 1983. Determination of nutrients. p. 125–139.In K. Grasshoff, M. Ehrhardt, and K. Kremling (eds.) Methods of Seawater Analysis. Verlag Chemie, Weinheim, Germany.
Kostka, J. E. and G. W. Luther III. 1994. Partitioning and speciation of solid phase iron in saltmarsh sediments. Geochimica et Cosmochimica Acta 58:1701–1710.
Lijklema, L. 1980. Interaction of orthophosphate with iron(III) and aluminum hydroxides. Environmental Science and Technology 14:537–541.
Lovley, D. R. and E. J. P. Phillips. 1986. Organic matter mineralization with reduction of ferric iron in anaerobic sediments. Applied and Environmental Microbiology 51:683–689.
Madrid, L. and P. D. Arambarri. 1985. Adsorption of phosphate by two iron oxides in relation to their porosity. Journal of Soil Science 36:523–530.
McKeague, J. A. and J. H. Day. 1966. Dithionite- and oxalate-extractable Fe and Al as aids in differentiating varicus classes of soils. Canadian Journal of Soil Science 46:13–22.
Malcolm, R. 1990. The uniqueness of humic substances in each of soil, stream and marine environments. Analytica Chimica Acta 232:19–30.
Moore, P. A. and K. R. Reddy. 1994. Role of Eh and pH on phosphorus geochemistry in sediments of Lake Okeechobee, Florida. Journal of Environmental Quality 23:955–964.
Murphy, J. and J. P. Riley. 1962. A modified single solution method for the determination of phosphate in natural waters. Analytica Chimica Acta 27:31–36.
Nelson, D. W. and L. E. Sommers. 1982. Total carbon, organic carbon, and organic matter, p. 539–579.In A. L. Page, R.H. Miller, and D.R. Keeney (eds.) Methods of Soil Analysis. Part 2-Chemical and Microbiological Properties. Agronomy 9. American Society of Agronomy, Inc. Soil Science Society of America, Inc., Madison, WI, USA.
Odgaard, B. V. 1993. The sedimentary record of spheroidal carbonaceous fly-ash in shallow Danish lakes. Journal of Paleolimnology 8:171–187.
Olsen, S. R. and L. E. Sommers. 1982. Phosphorus. p. 403–430.In A. L. Page, R.H. Miller, and D.R. Keeney (eds.) Methods of Soil Analysis Part 2-Chemical and Microbiological Properties Agronomy 9. American Society of Agronomy, Inc. Soil Science Society of America, Inc., Madison, WI, USA.
Oluyedun, O. A., S. O. Ajayi, and G. W. van Loon. 1991. Methods for fractionation of organic phosphorus in sediments. The Science of the Total Environment 106:243–252.
Phillips, E. J. P. and D. R. Lovley. 1987. Determination of Fe(III) and Fe(II) in oxalate extracts of sediment. Soil Science Society of America Journal 51:938–941.
Potter, R. L., C. F. Jordan, R. M. Guedes, G. J. Batmanian, and X. G. Han. 1991. Assessment of a phosphorus fractionation method for soils: problems for further investigation. Agriculture. Ecosystems and Environment 34:453–463.
Psenner, R., R. Pucsko, and M. Sager. 1984. Die fractionerung organisher und anorganisher Phosphorverbindungen von Sedimenten. Archiv fur Hydrobiologie—Supplementband 70:111–155.
Psenner, R. and R. Pucsko. 1988. Phosphorus fractionation: advantages and limits of the method for study of sediment P orgins and interactions. Archiv fur Hydrobiologie Beiheft—Ergebnisse der Limnologie 30:43–59.
Psenner, R., B. Boström, M. Dinka, K. Pettersson, R. Pucsko, and M. Sager. 1988. Fractionation of phosphorus in suspended matter and sediment. Archiv fur Hydrobiologie Beiheft—Ergebnisse der Limnologie 30:98–110.
Rapin, F., A. Tessier, P. G. C. Campbell, and R. Carignan. 1986. Potential artifacts in the determination of metal partitioning in sediments by a sequential extraction procedure. Environmental Science and Technology 20:836–840.
Richardson, C. 1985. Mechanisms controlling phosphorus retention capacity in freshwater wetlands. Science 228:1424–1427.
SAS Institute. 1988. SAS User’s Guide: STAT. SAS Institute Inc. Cary, NC, USA.
Stevens, R. J. and B. M. Stewart. 1982. Concentration, fractionation and characterisation of soluble organic phosphorus in river water entering Lough Neagh. Water Research 16:1507–1519.
Stookey, L. L. 1970. Ferrozine—a new spectrophotometric reagent for iron. Analytical Chemistry 42:779–781.
Stumm, W. and J. J. Morgan. 1981: Aquatic Chemistry. John Wiley and Sons, Inc., New York, NY, USA.
Sørensen, J. 1982. Reduction of ferrie iron in anaerebic, marine sediment and interaction with reduction of nitrate and sulfate. Applied and Environmental Microbiology 43:319–324.
Walbridge, M. R. and J. Struthers. 1993. Phosphorus retention in non-tidal palustrine forested wetlands of the mid-atlantic region. Wetlands 13:89–94.
Walbridge, M. R., C. J. Richardson, and W. T. Swank. 1991. Vertical distribution of biological and geochemical phosphorus subcycles in two Appalachian forest soils. Biogeochemistry 13:61–85.
White, R. E. and G. W. Thomas. 1981. Hydrolysis of aluminium on weakly acidic organic exchangers: implications for phosphate adsorption. Fertilizer Research 2:159–167.
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Paludan, C., Jensen, H.S. Sequential extraction of phosphorus in freshwater wetland and lake sediment: Significance of humic acids. Wetlands 15, 365–373 (1995). https://doi.org/10.1007/BF03160891
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DOI: https://doi.org/10.1007/BF03160891