Physical Fractionation of Soil and Organic Matter in Primary Particle Size and Density Separates

  • Bent T. Christensen
Part of the Advances in Soil Science book series (SOIL, volume 20)


The soil organic matter (SOM) pool encompasses plant, animal, and microbial residues in all stages of decay and a diversity of heterogeneous organic substances intimately associated with inorganic soil components. The soil microbiota and fine roots may also be considered part of the SOM pool. The turnover of the different SOM components varies continuously due to the complex interaction of biological, chemical, and physical processes in soil. The complexity of SOM and its importance to soil fertility have challenged generations of soil scientists, and numerous studies, of which some date back more than two centuries (see historical review in Kononova, 1961), have covered a vast array of aspects of SOM.


Soil Organic Matter Content Light Fraction Heavy Fraction Ultrasonic Dispersion Fine Clay 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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  1. Adams, T. McM. 1980. Macro organic matter content of some Northern Ireland soils.Record Agric. Res28: 1–11Google Scholar
  2. Adams, TMM 1982. The effects of agronomy on C and N distribution in soil organo-mineral fractions.J. Agric. Sci. Camb98: 335–342CrossRefGoogle Scholar
  3. Adams, W.A., and V.I. Stewart. 1969. The effect of ultrasonic dispersion on silurian shale particles. Soil Sci. 108: 227–228CrossRefGoogle Scholar
  4. Ahl, C. 1984. Veränderungen der Art und Menge der organischen Substanz in der Ackerkrume von Langzeit-Feldversuchen, gemessen an einigen physikalischen und chemischen Parametern. Ph.D. thesis, Georg-August-Universität, Göttingen, Germany.Google Scholar
  5. Ahl, C., H.-J. Altemüller, and H. Söchtig. 1983. Einfluss von Bodentyp, Standort und pflanzenbaulichen Massnahmen auf den Anteil organicher Substanz in verschiedenen Mikroaggregatgrössenklassen am Gesamtboden.Mitteilgn. Dtsch. Bodenkundl. Gesellsch38: 177–182Google Scholar
  6. Ahl, C., H.-J. Altemüller, and H. Söchtig. 1985. Die Tonverteilung auf verschiedene Aggregatgrössenfraktionen des Bodens in Abhängigheit von der organischen Düngung.Mitteilgn. Dtsch. Bodenkundl. Gesellsch43: 325–329Google Scholar
  7. Ahmed, M., and J.M. Oades. 1984. Distribution of organic matter and adenosine triphosphate after fractionation of soils by physical procedures.Soil Biol. Biochem16: 465–470CrossRefGoogle Scholar
  8. Allison, F.E., M.S. Sherman, and L.A. Pinck. 1949. Maintenance of soil organic matter: I. Inorganic soil colloid as a factor in retention of carbon during formation of humus.Soil Sci68: 463–478CrossRefGoogle Scholar
  9. Amato, M., and J.N. Ladd. 1980. Studies of nitrogen immobilization and mineralization in calcareous soils-V. Formation and distribution of isotope-labelled biomass during decomposition of 14C- and 15N-labelled plant material.Soil Biol. Biochem12: 405–411CrossRefGoogle Scholar
  10. Amato, M., J.N. Ladd, A. Ellington, G. Ford, J.E. Mahoney, A.C. Taylor, and D. Walsgott. 1987. Decomposition of plant material in Australian soils. IV. Decompositionin situof 14C- and 15N-labelled legume and wheat materials in a range of Southern Australian soils.Aust. J. Soil Res25: 95–105CrossRefGoogle Scholar
  11. Anderson, D.W., and E.A. Paul. 1984. Organo-mineral complexes and their study by radiocarbon dating.Soil Sci. Soc. Amer. J48: 298–301CrossRefGoogle Scholar
  12. Anderson, D.W., S. Saggar, J.R. Bettany, and J.W.B. Stewart. 1981. Particle size fractions and their use in studies of soil organic matter: I. The nature and distribution of forms of carbon, nitrogen and sulfur.Soil Sci. Soc. Amer. J45: 767–772CrossRefGoogle Scholar
  13. Anderson, T.H., and K.H. Domsch. 1989. Der Einfluss des Bodengefüges auf mikrobielle Stoffwechselleistungen.Mitteilgn. Dtsch. Bodenkundl. Gesellsch59: 523–528Google Scholar
  14. Andreux, F., S. Bruckert, A. Correa, and B. Souchier. 1980. Sur une méthode de fractionnement physique et chimique des agrégats des sols: origines possibles de la matière organique des fractions obtenues.C. R. Acad. Sc. Paris, Série D291: 381–384Google Scholar
  15. Angers, D.A., and G.R. Mehuys. 1990. Barley and alfalfa cropping effects on carbohydrate contents of a clay soil and its size fractions.Soil Biol. Biochem22: 285–288CrossRefGoogle Scholar
  16. Armour, J.D., G.S.P. Ritchie, and A.D. Robson. 1990. Extractable zinc in particle size fractions of soils from Western Australia and Queensland.Aust J. Soil Res28: 387–397CrossRefGoogle Scholar
  17. Arshad, M.A., and L.E. Lowe. 1966. Fractionation and characterization of naturally occurring organo-clay complexes.Soil Sci. Soc. Amer. Proc30: 731–735CrossRefGoogle Scholar
  18. Atchley, A.A., L.A. Crum. 1988. Acoustic cavitation and bubble dynamics. pp. 1–64. In K.S. Suslick (ed.). Ultrasound: Its Chemical, Physical and Biological Effects. VCH Publishers, New York, USA.Google Scholar
  19. Baldock, J. A., J.M. Oades, A.M. Vassallo, and M.A. Wilson. 1989. Incorporation of uniformly labelled13C-glucose carbon into the organic fraction of a soil. Carbon balance and CP/MAS13C NMR measurements.Aust. J. Soil Res27: 725–746CrossRefGoogle Scholar
  20. Baldock, J.A., J.M. Oades, A.M. Vassallo, and M.A. Wilson. 1990. Solid CP/MAS13C N.M.R. analysis of particle size and density fractions of a soil incubated with uniformly labelled13C-glucose.Aust. J. Soil Res28: 193–212CrossRefGoogle Scholar
  21. Balesdent, J., A. Mariotti, and B. Guillet. 1987. Natural13C abundance as a tracer for studies of soil organic matter dynamics.Soil Biol. Biochem19: 25–30CrossRefGoogle Scholar
  22. Balesdent, J., G.H. Wagner, and A. Mariotti. 1988. Soil organic matter turnover in long-term field experiments as revealed by carbon-13 natural abundance.Soil Sci. Soc. Amer. J52: 118–124CrossRefGoogle Scholar
  23. Barkoff, E. 1960. Über die Anwendung von Ultraschall zur Steigerung der Reaktionsgeschwindigkeit und zum Dispergieren des Bodens bei Bodenanalytischen Arbeiten.J. Sci. Agric. Soc. Finland32: 179–185Google Scholar
  24. Bernhard-Reversat, F. 1981. Participation of light and organo-mineral fractions of soil organic matter in nitrogen mineralization in a Sahelian savanna soil.Zbl. Bakt. II. Abt136: 281–290Google Scholar
  25. Bonde, T.A., B.T. Christensen, and C.C. Cerri. 1992. Dynamics of soil organic matter as reflected by naturall3C abundance in particle size fractions of forested and cultivated oxisols organic matter.Soil Biol. Biochem23: 275–277CrossRefGoogle Scholar
  26. Bourget, S.J. 1968. Ultrasonic vibration for particle-size analyses.Can. J. Soil Sci48: 372–373CrossRefGoogle Scholar
  27. Braunack, M.V., and A.R. Dexter. 1989. Soil aggregation in the seedbed: A review. I. Properties of aggregates and beds of aggregates. Soil Tillage Res. 14: 259–279CrossRefGoogle Scholar
  28. Broersma, K., and L.M. Lavkulich. 1980. Organic matter distribution with particle-size in surface horizons of some sombric soils in Vancouver Island.Can. J. Soil Sci60: 583–586CrossRefGoogle Scholar
  29. Bruckert, S., and G. Kilbertus. 1980. Fractionnement et analyse des complexes organo mineraux de sols bruns et de chernozems.Plant Soil57: 271–295CrossRefGoogle Scholar
  30. Busacca, A.J., J.R. Aniku., and M.J. Singer. 1984. Dispersion of soils by an ultrasonic method that eliminates probe contact.Soil Sci. Soc. Amer. J48: 1125–1129CrossRefGoogle Scholar
  31. Cameron, R.S., and A.M. Posner. 1979. Mineralisable organic nitrogen in soil fractionated according to particle size.J. Soil Sci30: 565–577CrossRefGoogle Scholar
  32. Catroux, G., and M. Schnitzer. 1987. Chemical, spectroscopic, and biological characteristics of the organic matter in particle size fractions separated from an Aquoll.Soil Sci. Soc. Amer. J51: 1200–1207CrossRefGoogle Scholar
  33. Cerri, C., C. Feller, J. Balesdent, R. Victoria, and A. Plenecassagne. 1985. Application du tracage isotopique naturel en13C, a létude de la dynamique de la matiere organique dans les sols.C. R. Acad. Sc. Paris, Serie II300: 423–428Google Scholar
  34. Cheshire, M.V., and C.M. Mundie. 1981. The distribution of labelled sugars in soil particle size fractions as a means of distinguishing plant and microbial carbohydrate residues.J. Soil Sci32: 605–618CrossRefGoogle Scholar
  35. Cheshire, M.V., and C.M. Mundie. 1990. Organic matter contributed to soil by plant roots during the growth and decomposition of maize.Plant Soil121: 107–114CrossRefGoogle Scholar
  36. Cheshire, M.V., B.T. Christensen, and L.H. Sørensen. 1990. Labelled and native sugars in particle-size fractions from soils incubated with14C straw for 6 to 18 years.J. Soil Sci41: 29–39CrossRefGoogle Scholar
  37. Chichester, F.W. 1969. Nitrogen in soil organo-mineral sedimentation fractions. Soil Sci. 107: 356–363CrossRefGoogle Scholar
  38. Chichester, F.W. 1970. Transformations of fertilizer nitrogen in soil. II. Total and NI5-labelled nitrogen of soil organo-mineral sedimentation fractions.Plant Soil33: 437–456CrossRefGoogle Scholar
  39. Chiou, C.T., J-F. Lee, and S.A. Boyd. 1990. The surface area of soil organic matter.Environ. Sci. Technol24: 1164–1166CrossRefGoogle Scholar
  40. Christensen, B.T. 1985. Carbon and nitrogen in particle size fractions isolated from Danish arable soils by ultrasonic dispersion and gravity-sedimentation.Acta Agric. Scand35: 175–187CrossRefGoogle Scholar
  41. Christensen, B.T. 1986. Straw incorporation and soil organic matter in macro- aggregates and particle size separates.J. Soil Sci37: 125–135CrossRefGoogle Scholar
  42. Christensen, B.T. 1987a. Decomposability of organic matter in particle size fractions from field soils with straw incorporation.Soil Biol. Biochem19: 429–435CrossRefGoogle Scholar
  43. Christensen, B.T. 1987b. Use of particle size fractions in soil organic matter studies. Intecol Bull. 15: 113–123Google Scholar
  44. Christensen, B.T. 1988. Effects of animal manure and mineral fertilizer on the total carbon and nitrogen contents of soil size fractions.Biol. Fertil. Soils5: 304–307CrossRefGoogle Scholar
  45. Christensen, B.T., and S. Bech-Andersen. 1989. Influence of straw disposal on distribution of amino acids in soil particle size fractions.Soil Biol. Biochem21: 35–40CrossRefGoogle Scholar
  46. Christensen, B.T., and L.H. Sørensen. 1985. The distribution of native and labelled carbon between soil particle size fractions isolated from long-term incubation experiments.J. Soil Sci36: 219–229CrossRefGoogle Scholar
  47. Christensen, B.T., and L.H. Sørensen. 1986. Nitrogen in particle size fractions of soils incubated for five years with15N-ammonium and14C-hemicellulose.J. Soil Sci37: 241–247CrossRefGoogle Scholar
  48. Christensen, B.T., F. Bertelsen, and G. Gissel-Nielsen. 1989. Selenite fixation by soil particle-size separates.J. Soil Sci40: 641–647CrossRefGoogle Scholar
  49. Christensen, S., and B.T. Christensen. 1991. Organic matter available for denitrification in different soil fractions: effect of freeze/thaw cycles and straw disposal.J. Soil Sci42: 637–647CrossRefGoogle Scholar
  50. Christenson, D.R., and E.C. Doll. 1973. Release of magnesium from soil clay and silt fractions during cropping.Soil Sci. 116:59–63CrossRefGoogle Scholar
  51. Churchman, G.J., and K.R. Tate. 1986. Aggregation of clay in six New Zealand soil types as measured by disaggregation procedures.Geoderma 37: 207–220CrossRefGoogle Scholar
  52. Coleman, D.C., J.M. Oades, and G. Uehara (eds.) 1989.Dynamics of Soil Organic Matter in Tropical Ecosystems. NifTAL Project, University of Hawaii at Manoa, USAGoogle Scholar
  53. Cooley, J.H. (ed.) 1987.Soil Organic Matter Dynamics and Soil Productivity. Intecol Bull. 15. The International Association for Ecology, Athens, Georgia, USAGoogle Scholar
  54. Curtin, D., P.M. Huang, and H.P.W. Rostad. 1987. Components and particle size distribution of soil titratable acidity.Soil Sci. Soc. Amer. J51: 332–336CrossRefGoogle Scholar
  55. Dalal, R.C., and R.J. Henry. 1988. Cultivation effects on carbohydrate contents of soil and soil fractions.Soil Sci. Soc. Amer. J52: 1361–1365CrossRefGoogle Scholar
  56. Dalal, R.C., and R.J. Mayer. 1986a. Long-term trends in fertility of soils under continuous cultivation and cereal cropping in Southern Queensland. I. Overall changes in soil properties and trends in winter cereal yields.Aust. J. Soil Res24: 265–279CrossRefGoogle Scholar
  57. Dalal, R.C., and R.J. Mayer. 1986b. Long-term trends in fertility of soils under continuous cultivation and cereal cropping in Southern Queensland. II. Total organic carbon and its rate of loss from the soil profile.Aust. J. Soil Res24: 281–292CrossRefGoogle Scholar
  58. Dalal, R.C. R.J Mayer 1986c Long-term trends in fertility of soils under continuous cultivation and cereal cropping in Southern Queensland. III. Distribution and kinetics of soil organic carbon in particle-size fractions.Aust. J. Soil Res 24:293–300CrossRefGoogle Scholar
  59. Dalal, R.C. R.J. Mayer. 1986d. Long-term trends in fertility of soils under continuous cultivation and cereal cropping in Southern Queensland. IV. Loss of organic carbon from different density fractions.Aust. J. Soil Res24: 301–309CrossRefGoogle Scholar
  60. Dalal, R.C., and R.J. Mayer. 1987. Long-term trends in fertility of soils under continuous cultivation and cereal cropping in Southern Queensland. VI. Loss of total nitrogen from different particle-size and density fractions.Aust. J. Soil Res 25: 83–93CrossRefGoogle Scholar
  61. Dong, A., G.V. Simsiman, and G. Chesters. 1983. Particle-size distribution and phosphorus levels in soil, sediment, and urban dust and dirt samples from the Menomonee River Watershed, Wisconsin, U.S.A.Water Res. 17: 569–577CrossRefGoogle Scholar
  62. Dong, A., G.V. Simsiman, and G. Ghesters. 1985. Release of phosphorus and metals from soils and sediments during dispersion.Soil Sci. 139:97–99CrossRefGoogle Scholar
  63. Dormaar, J.F. 1983. Chemical properties of soil and water-stable aggregates after sixty-seven years of cropping to spring wheat.Plant Soil 75: 51–61CrossRefGoogle Scholar
  64. Drake, E.H., and H.L. Motto. 1982. An analysis of the effect of clay and organic matter content on the cation exchange capacity of New Jersey soils.Soil Sci. 133:281–288CrossRefGoogle Scholar
  65. Dudas, M.J., and S. Pawluk. 1970. Naturally occurring organo-clay complexes of orthic black chernozems.Geoderma 3: 5–17CrossRefGoogle Scholar
  66. Dzurec, R.S., T.W. Boutton, M.M. Caldwell, and B.N. Smith. 1985. Carbon isotope ratios of soil organic matter and their use in assessing community composition changes in Curlew Valley, Utah.Oecologia 66: 17–24CrossRefGoogle Scholar
  67. Edwards, A.P., and J.M. Bremner. 1964. Use of sonic vibration for separation of soil particles.Can. J. Soil Sci 44:366CrossRefGoogle Scholar
  68. Edwards, A.P., and J.M. Bremner. 1965. Dispersion of mineral colloids in soils using cation exchange resins.Nature 205: 208–209CrossRefGoogle Scholar
  69. Edwards, A.P., and J.M. Bremner. 1967. Dispersion of soil particles by sonic vibration.J.Soil Sci. 18:47–63CrossRefGoogle Scholar
  70. Elliott, E.T. 1986. Aggregate structure and carbon, nitrogen, and phosphorous in native and cultivated soils.Soil Sci. Soc. Amer. J 50: 627–633CrossRefGoogle Scholar
  71. Elliott, E.T. and C.A. Cambardella. 1991. Physical separation of soil organic matter.Agric. Ecosyst. Environ 34: 407–419CrossRefGoogle Scholar
  72. Elonen, P . 1971. Particle-size analysis of soil.Acta Agralia Fennica no 122Google Scholar
  73. Elustondo, J. D.A. Angers, M.R. Laverdiere, A. N’Dayegamiye. 1990. Étude comparative de l’ágrégation et de la matiére organique associée aux fractions granulométriques de sept sols sous culture de maïs ou en prairie.Can. J. Soil Sci 70: 395–402CrossRefGoogle Scholar
  74. Emerson, W.W. 1959. The structure of soil crumbs.J. Soil Sci 10: 235–244CrossRefGoogle Scholar
  75. Emerson, W.W. 1971. Determination of the contents of clay-sized particles in soils.J. Soil Sci 22: 50–59CrossRefGoogle Scholar
  76. Emerson, W.W. R.C. Forster J.M. Oades. 1986. Organo-mineral complexes in relation to soil aggregation and structure,pp. 521–548. In P.M. Huang M. Schnitzer (eds.).Interactions of Soil Minerals with Natural Organics and Microbes. SSSA, Madison, WI., USA.Google Scholar
  77. Essington, M.E., and S.V. Mattigod. 1990. Element partitioning in size- and density-fractionated sewage sludge and sludge-amended soil.Soil Sci. Soc. Amer. J 54: 385–394CrossRefGoogle Scholar
  78. Evans, K.M., R.A. Gill, and P.W.J. Robotham. 1990. The PAH and organic content of sediment particle size fractions.Water Air Soil Poll 51: 13–31CrossRefGoogle Scholar
  79. Feller, C. 1979. Une méthode de fractionnement granulométrique de la matière organique des sols.Cahier ORSTOM, serie Pedologie 17: 339–346Google Scholar
  80. Filip, Z. 1977. Einfluss von Tonmineralen auf die mikrobielle Ausnutzung der kohlenstoffhaltigen Substanzen und Bildung der Biomasse.Ecol. Bull. (Stockh.) 25: 173–179Google Scholar
  81. Fog, K. 1988. The effect of added nitrogen on the rate of decomposition of organic matter.Biol. Rev 63: 433–462CrossRefGoogle Scholar
  82. Ford, G.W. D.J. Greenland. 1968. The dynamics of partly humified organic matter in some arable soils.Trans. 9th Int. Congr. Soil Sci., Adelaide, 2: 403–410Google Scholar
  83. Ford, G.W., D.J. Greenland, and J.M. Oades. 1969. Seperation of the light fraction from soils by ultrasonic dispersion i halogenated hydrocarbons containing a surfactant.J. Soil Sci 20: 291–296CrossRefGoogle Scholar
  84. Förstner U. 1985. Chemical forms and reactivities of metals in sediments. pp. 1–30. In R. Leschber R.D. Davies P. L’Hermite (eds.)Chemical Methods for Assessing Bio-Available Metals in Sludges and Soils. Elsevier Applied Science Publ., London, UKGoogle Scholar
  85. Francis, C.W. 1973. Adsorption of polyvinylpyrrolidone on reference clay minerals.Soil Sci. 115:40–54CrossRefGoogle Scholar
  86. Garwood, E.A., C.R. Clement, and T.E. Williams. 1972. Leys and soil organic matter III. The accumulation of macro-organic matter in the soil under different swards.J. agric. Sci. Camb 78: 333–341CrossRefGoogle Scholar
  87. Gee, G.W. J.W. Bauder. 1986. Particle-size analysis, pp. 383– 441. In A. Klute (ed.),Methods of Soil Analysis, Part 1, 2nd Edition. ASA and SSSA Publ., Madison, WI, USAGoogle Scholar
  88. Genrich, D.A., and J.M. Bremner. 1972a. A reevaluation of the ultrasonic- vibration method of dispersing soils.Soil Sci. Soc. Amer. Proc 36: 944–947CrossRefGoogle Scholar
  89. Genrich, D.A., and J.M. Bremner. 1972b. Effect of probe condition on ultrasonic dispersion of soils by probe-type ultrasonic vibrators.Soil Sci. Soc. Amer. Proc 36: 975–976CrossRefGoogle Scholar
  90. Genrich, D.A., and J.M. Bremner. 1974. Isolation of soil particle-size fractions.Soil Sci. Soc. Amer. Proc 38: 222–225CrossRefGoogle Scholar
  91. Gerzabek, M.H., and S.M. Ullah. 1988. Über die Verteilung von137Cs in den Korngrössenfraktionen zweier kontaminierter Böden.Die Bodenkultur 39: 293–297Google Scholar
  92. Greenland, D.J. 1965a. Interaction between clays and organic compounds in soils. Part I. Mechanisms of interaction between clays and defined organic compounds.Soils Fert. 28:415–425Google Scholar
  93. Greenland, D.J. 1965b. Interaction between clays and organic compounds in soils. Part II. Adsorption of soil organic compounds and its effect on soil properties.Soils Fert. 28:521–532Google Scholar
  94. Greenland, D.J. 1971. Changes in the nitrogen status and physical condition of soils under pastures, with special reference to the maintenance of the fertility of Australian soils used for growing wheat.Soils Fert. 34:237–251Google Scholar
  95. Greenland, D.J., and G.W. Ford. 1964. Seperation of partially humified organic materials from soils by ultrasonic dispersion.Trans. 8th Int. Congr. Soil Sci., Bucharest, 3: 137–148Google Scholar
  96. Gregorich, E.G. 1989.The effects of texture on the stabilization and physical protection of organic matter in soil. Ph.D. thesis, The Faculty of Graduate Studies, University of Guelph, Ontario, CanadaGoogle Scholar
  97. Gregorich, E.G., R.G. Kachanoski, and R.P. Voroney. 1988. Ultrasonic dispersion of aggregates: Distribution of organic matter in size fractions.Can. J. Soil. Sci 68: 395–403CrossRefGoogle Scholar
  98. Gregorich, E.G., R.G. Kachanoski, and R.P. Voroney. 1989. Carbon mineralization in soil size fractions after various amounts of aggregate disruption.J. Soil Sci 40: 649–659CrossRefGoogle Scholar
  99. Gregorich, E.G., R.P. Voroney, and R.G. Kachanoski. 1991. Turnover of carbon through the microbial biomass in soils with different textures.Soil Biol. Biochem 23: 799–805CrossRefGoogle Scholar
  100. Hamblin, A.P. 1977. Structural features of aggregates in some East Anglian silt soils.J. Soil Sci 28: 23–28CrossRefGoogle Scholar
  101. Hamdy, A.A., and G. Gissel-Nielsen. 1977. Fixation of selenium by clay minerals and iron oxides.Z. Pflanzenernaehr. Bodenkd 140: 63–70CrossRefGoogle Scholar
  102. Healy, W.B., and G.G.C. Claridge. 1974. Chemical properties of soil particle size fractions separated by ultrasonic dispersion.New Zealand J. Sci 17: 493–501Google Scholar
  103. Hinds, A.A., and L.E. Lowe. 1980a. The use of an ultrasonic probe in soil dispersion and in the bulk isolation of organo-mineral complexes.Can. J. Soil Sci 60: 389–392CrossRefGoogle Scholar
  104. Hinds, A.A., and L.E. Lowe. 1980b. Distribution of carbon, nitrogen, sulphur and phosphorus in particle-size separates from gleysolic soils.Can. J. Soil Sci 60: 783–786CrossRefGoogle Scholar
  105. Hinds, A.A., and L.E. Lowe. 1980c. Dispersion and dissolution effects during ultrasonic dispersion of gleysolic soils in water and in electrolytes.Can. J. Soil Sci 60: 329–335CrossRefGoogle Scholar
  106. Huang P.M. M. Schnitzer (eds.) 1986.Interactions of Soil Minerals with Natural Organics and Microbes SSSA Publ. Inc. Madison, WI, USA.Google Scholar
  107. Huang P.M. R. Grover, R.B. McKercher 1984Components and particle size fractions involved in atrazine adsorption by soils.Soil Sci 138:20–24CrossRefGoogle Scholar
  108. IAEA. 1977.Soil organic Matter Studies, Vol. I,II. International Atomic Energy Agency, Vienna, Austria.Google Scholar
  109. Janzen, H.H. 1987. Soil organic matter characteristics after long-term cropping to various spring wheat rotations.Can. J. Soil Sci 67: 845–856CrossRefGoogle Scholar
  110. Jenkinson, D.S. 1977. Studies on the decomposition of plant material in soil. V. The effects of plant cover and soil type on the loss of carbon froml4C labeled ryegrass decomposing under field conditions.J. Soil Sci 28: 424–434CrossRefGoogle Scholar
  111. Jenkinson, D.S. J.N.Ladd. 1981 Microbial biomass in soil: Measurement and turnover. pp. 415–471. In E.A. PaulJ.N.Ladd (eds.),Soil Biochemistry, vol. 5 Marcel Dekker New York, USA.Google Scholar
  112. Jenkinson, D.S., D.S. Powlson, and R.W.M. Wedderburn. 1976. The effects of biocidal treatments on metabolism in soil—III. The relationship between soil biovolume, measured by optical microscopy, and the flush of decomposition caused by fumigation.Soil Biol. Biochem 8: 189–202CrossRefGoogle Scholar
  113. Jenkinson, D.S., P.B.S. Hart, J.H. Rayner, and L.C. Parry. 1987. Modelling the turnover of organic matter in long-term experiments at Rothamsted.Intecol. Bull 15: 1–8Google Scholar
  114. Jensen, E.S., B.T. Christensen, and L.H. Sørensen. 1989. Mineral-fixed ammonium in clay- and silt-size fractions of soils incubated with15N-ammonium sulphate for five years.Biol. Fertil. Soils8: 298–302CrossRefGoogle Scholar
  115. Jensen, V. A. Kjøller L.H. Sørensen (eds.) 1986.Microbial Communities in Soil Elsevier Applied Sci. Publ., London, UKGoogle Scholar
  116. Kaila, A. 1967. Potassium status in different particle size fractions of some Finnish soils.J. Sci. Agric. Soc. Finland39: 45–56Google Scholar
  117. Kaila, A., and R. Ryti. 1968. Calcium, magnesium and potassium in clay, silt and fine sand fractions of some Finnish soils.J. Sci. Agric. Soc. Finland 40: 1–13Google Scholar
  118. Kanazawa, S., and Z. Filip. 1986. Distribution of microorganisms, total biomass, and enzyme activities in different particles of Brown soil.Microb. Ecol 12: 205–215CrossRefGoogle Scholar
  119. Khan, A. 1979. Distribution of DTPA-extractable Fe, Zn and Cu in soil particle- size fractions.Commun. Soil Sci. Plant Anal 10: 1211–1218CrossRefGoogle Scholar
  120. Koenigs, F.F.R. 1978. Comments on the paper by P.F. North: Towards an absolute measurement of soil structural stability using ultrasound.J. Soil Sci29: 117–120CrossRefGoogle Scholar
  121. Kononova, M.M. 1961.Soil Organic Matter—Its Nature, Its Role in Soil Formation and in Soil Fertility Pergamon Press Oxford, UKGoogle Scholar
  122. Kowalenko, C.G., and G.J. Ross. 1980. Studies on the dynamics of “recently” clay-fixed NH4 + usingl5N.Can. J. Soil Sci60: 61–70CrossRefGoogle Scholar
  123. Kyuma, K, A. Hussain, and K. Kawaguchi. 1969. The nature of organic matter in soil organo-mineral complexes.Soil Sci. Plant Nutr 15: 149–155Google Scholar
  124. Ladd, J.N., and M. Amato. 1980. Studies of nitrogen immobilization and mineralization in calcareous soils-IV. Changes in the organic nitrogen of light and heavy subfractions of silt- and fine clay-size particles during nitrogen turnover.Soil. Biol. Biochem 12: 185–189CrossRefGoogle Scholar
  125. Ladd, J.N., J.W. Parsons, and M. Amato. 1977a. Studies of nitrogen immobilization and mineralization in calcareous soils-I. Distribution of immobilized nitrogen amongst soil fractions of different particle size and density.Soil Biol. Biochem 9: 309–318CrossRefGoogle Scholar
  126. Ladd, J.N., J.W. Parsons, and M. Amato. 1977b. Studies of nitrogen immobilization and mineralization in calcareous soils-II. Mineralization of immobilized nitrogen from soil fractions of different particle size and density.Soil Biol. Biochem 9: 319–325CrossRefGoogle Scholar
  127. Ladd, J.N. M.Amato J.W. Parsons. 1977c Studies of nitrogen immobilization and mineralization in calcareous soils. III. Concentration and distribution of nitrogen derived from the soil biomass. pp.301–311. InSoil Organic Matter Studies, vol. 1. IAEA, Vienna, AustriaGoogle Scholar
  128. Ladd, J.N. M. Amato, J.M. Oades. 1985. Decomposition of plant material in Australian soils. III. Residual organic and microbial biomass C and N from isotope-labelled legume material and soil organic matter, decomposing under field conditions.Aust. J. Soil Res 23: 603–611CrossRefGoogle Scholar
  129. Lagaly, G. 1984. Clay-organic interactions.Phil. Trans. R. Soc. Lond. A 311: 315–332CrossRefGoogle Scholar
  130. Leinweber P 1988.Erfassung und Charakterisierung organisch-mineralischer Komplexe (OMK) und ihrer Differenzierung in Böden von Dauerveldversuchen der DDR Ph.D. thesis, Diss. A., Wilhelm-Pieck-Universität, Rostock, GermanyGoogle Scholar
  131. Leinweber, P., and G. Reuter. 1988. Menge und Qualität organisch-mineralischer Komplexe in Böden unterschiedlicher Standorte.Tag.-Ber. Akad. Landwirtsch.- Wiss DDR. 269: 223–235Google Scholar
  132. Lemieux, G.J. 1964. Efficiency of various shakers in the particle-size analysis of soils.Can. J. Soil Sci 44: 228–231CrossRefGoogle Scholar
  133. Leuschner, H.H., R. Aldag, and B. Meyer. 1981. Dichte-Fraktionierung des Humus in Ap-Horizonten von Sandböden mit unterschiedlicher Körnung und Nutzungs-Vorgeschichte.Mitteilgn. Dtsch. Bodenkundl. Gesellsch32: 583–592Google Scholar
  134. Lichtfuss, R., and G. Brümmer. 1981. Gehalte an Organischer Substanz, Schwermetallen und Phosphor in Dichtefraktionen von Fluvialen Unterwasserböden.Geoderma 25: 245–265CrossRefGoogle Scholar
  135. Livens, F.R., and M.S. Baxter. 1988. Particle size and radionuclide levels in some West Cumbrian soils.Sci. Tot. Environ 70: 1–17CrossRefGoogle Scholar
  136. Lowe, L.E., and A.A. Hinds. 1983. The mineralization of nitrogen and sulphur from particle size separates of gleysolic soils.Can. J. Soil Sci 63: 761–766CrossRefGoogle Scholar
  137. Lynch, D.L., L.M. Wright L.J. Cotnoir, jr 1956.The adsorption of carbohydrates and related compounds on clay minerals.Soil Sci. Soc. Amer. Proc 20: 6–9CrossRefGoogle Scholar
  138. Malone C.R. M.B. Swartout. 1969. Size, mass, and caloric content of particulate organic matter in old-field and forest soils.Ecology 50:395–399CrossRefGoogle Scholar
  139. Martin, A., A. Mariotti, J. Balesdent, P. Lavelle, and R. Vuattoux. 1990. Estimate of organic matter turnover rate in a savanna soil by 13C natural abundance measurements.Soil Biol. Biochem 22: 517–523CrossRefGoogle Scholar
  140. McGill, W.B., and E.A. Paul. 1976. Fractionation of soil and15N nitrogen to separate the organic and clay interactions of immobilized N.Can. J. Soil Sci56: 203–212CrossRefGoogle Scholar
  141. McGill, W.B., J.A. Shields, and E.A. Paul. 1975. Relation between carbon and nitrogen turnover in soil organic fractions of microbial origin.Soil Biol. Biochem 7: 57–63CrossRefGoogle Scholar
  142. McKeague, J.A. 1971. Organic matter in particle-size and specific gravity fractions of some Ah horizons.Can. J. Soil Sci 51: 499–505CrossRefGoogle Scholar
  143. McTainsh, G.H., and N.C. Duhaylungsod. 1989. Aspects of soil particle-size analysis in Australia.Aust. J. Soil Res 27: 629–636CrossRefGoogle Scholar
  144. Molloy, L.F., and T.W. Speir. 1977. Studies on a climosequence of soils in tussock grasslands 12. Constituents of the soil light fraction.New Zealand J. Sci 20: 167–177Google Scholar
  145. Molloy, L.F., B.A. Bridger, and A. Cairns. 1977. Studies on a climosequence of soils in tussock grasslands. 13. Structural carbohydrates in tussock leaves, roots and litter and in the soil light and heavy fractions.New Zealand J. Sci 20: 443–451Google Scholar
  146. Monnier, G., L. Turc, and C. Jeanson-Luusinang. 1962. Une méthode defractionnement densimétrique par centrifugation des matières organiques du sol.Ann. Agron 13: 55–63Google Scholar
  147. Morra, M.J R.R. Blank L.L. Freeborn B. Shafii. 1991.Size fractionation of soil organo-mineral complexes using ultrasonic dispersion.Soil Sci 152:294–303.CrossRefGoogle Scholar
  148. Murayama, S. 1981. Persistency and monosaccharide composition of polysaccharides of soil which received no plant materials for certain period under field conditions.Soil Sci. Plant Nutr 27: 463–475Google Scholar
  149. Murayama, S. 1984. Changes in the monosaccharide composition during the decomposition of straws under field conditions.Soil Sci. Plant Nutr 30: 367–381Google Scholar
  150. Murayama, S., M.V. Cheshire, C.M. Mundie, G.P. Sparling, and H. Shepherd. 1979. Comparison of the contribution to soil organic matter fractions, particularly carbohydrates, made by plant residues and microbial products.J.Sci. Food Agric 30: 1025–1034CrossRefGoogle Scholar
  151. Murphy, E.M., J.M. Zachara, and S.T. Smith. 1990. Influence of mineral-bound humic substances on the sorption of hydrophobic organic compounds.Environ. Sci. Technol 24: 1507–1516CrossRefGoogle Scholar
  152. Nkedi-Kizza, P., P.S.C. Rao, and J.W. Johnson. 1983. Adsorption of diuron and 2,4,5-T on soil particle-size separates.J. Environ. Qual 12: 195–197CrossRefGoogle Scholar
  153. North. P.F. 1976. Towards an absolute measurement of soil structural stability using ultrasound.J. Soil Sci 27: 451–459CrossRefGoogle Scholar
  154. Oades, J.M. 1972. Studies on soil polysaccharides: III. Composition of polysaccharides in some Australian soils.Aust. J. Soil Res 10: 113–126CrossRefGoogle Scholar
  155. Oades, J.M. 1984. Soil organic matter and structural stability: mechanisms an implications for management.Plant Soil 76: 319–337CrossRefGoogle Scholar
  156. Oades, J.M. 1989. An introduction to organic matter in mineral soil. pp. 89–159. In: J.B. DixonS.B. Weed (eds.),Minerals in Soil Environments, Second Edition SSSA Publ. Inc. Madison, WI, USAGoogle Scholar
  157. Oades, J.M. and A.G. Waters. 1991. Aggregate hierarchy in soils.Aust. J. Soil Res 29: 815–828CrossRefGoogle Scholar
  158. Oades, J.M., A.M. Vassallo, A.G. Waters, and M.A. Wilson. 1987. Characterization of organic matter in particle size and density fractions from a red- brown earth by solid-state13C N.M.R.Aust. J. Soil Res 25: 71–82CrossRefGoogle Scholar
  159. Oades, J.M., A.G. Waters, A.M. Vasallo, M.A. Wilson, and G.P. Jones. 1988. Influence of management on the composition of organic matter in a red-brown earth as shown by13C nuclear magnetic resonance.Aust. J. Soil Res 26: 289–299CrossRefGoogle Scholar
  160. Parasher, C.D., and L.E. Lowe. 1970. Isolation of clay-size organo-mineral complexes from soils of the Lower Fraser Valley.Can. J. Soil Sci 50: 403–407CrossRefGoogle Scholar
  161. Parton, W.J., D.S. Schimel, C.V. Cole, and D.S. Ojima. 1987. Analysis of factors controlling soil organic matter levels in Great Plains grasslands.Soil Sci. Soc. Amer. J 51: 1173–1179CrossRefGoogle Scholar
  162. Paul, E.A. F.E. Clark. 1989.Soil Microbiology and BiochemistryAcademic Press Inc., San Diego, USAGoogle Scholar
  163. Paul, E.A., W.B. McGill. 1977. Turnover of microbial biomass, plant residues and soil humic constituents under field conditions, pp. 149–157. InSoil Organic Matter Studies, vol. 1. IAEA, Vienna, AustriaGoogle Scholar
  164. Plewinsky, B., and R. Kamps. 1984. Sodium metatungstate, a new medium for binary and ternary density gradient centrifugation.Makromol. Chem 185: 1429–1439CrossRefGoogle Scholar
  165. Pritchard, D.T. 1974. A method for soil particle-size analysis using ultrasonic disaggregation.J. Soil Sci 25: 34–40CrossRefGoogle Scholar
  166. Ramsay, A.J. 1984. Extraction of bacteria from soil: Efficiency of shaking or ultrasonication as indicated by direct counts and autoradiography.Soil Biol. Biochem16: 475–481CrossRefGoogle Scholar
  167. Reuter, G., and P. Leinweber. 1988. Konzeption und Methodik der Untersuchung organischmineralischer Komplexe (OMK) in Böden.Tag.-Ber., Akad. Landwirtsch.-Wiss. DDR 269: 213–222Google Scholar
  168. Richter, M., I. Mizuno, S. Aranguez, and S. Uriarte. 1975. Densimetric fractionation of soil organo-mineral complexes.J. Soil Sci 26: 112–123CrossRefGoogle Scholar
  169. Saly, R. 1967. Use of ultrasonic vibration for dispersing soil samples.Soviet Soil Sci 2: 1547–1559Google Scholar
  170. Scharpenseel, H.W., K. Tsutsuki, P. Becker-Heidmann, and J. Freytag. 1986. Untersuchungen zur Kohlenstoffdynamik und Bioturbation von Mollisolen. Z.Pflanzenernaehr. Bodenk 149: 582–597CrossRefGoogle Scholar
  171. Scheffer, B . 1977. Stabilization of organic matter in sand mixed cultures. pp. 359–363. InSoil Organic Matter Studies Vol. II, IAEA, Vienna, AustriaGoogle Scholar
  172. Schimel, D.S. 1986. Carbon and nitrogen turnover in adjacent grassland cropland ecosystems.Biogeochemistry 2: 345–357CrossRefGoogle Scholar
  173. Schlesinger, W.H. 1986. Changes in soil carbon storage and associated with disturbance and recovery, pp. 194–220 In J.R. Trabalka,D.E. Reichle (eds.)The Changing Carbon Cycle-A Global Analysis Springer- Verlag, New York, USAGoogle Scholar
  174. Schnitzer, M., and K.C. Ivarson. 1982. Different forms of nitrogen in particle size fractions separated from two soils.Plant Soil 69: 383–389CrossRefGoogle Scholar
  175. Schnitzer, M., and P. Schuppli. 1989a. The extraction of organic matter from selected soils and particle size fractions with 0.5 M NaOH and 0.1 M Na4P2O7 solutions.Can. J. Soil Sci 69: 253–262CrossRefGoogle Scholar
  176. Schnitzer, M., and P. Schuppli. 1989b. Method for the sequential extraction of organic matter from soils and soil fractions.Soil Sci. Soc. Amer. J 53: 1418–1424CrossRefGoogle Scholar
  177. Schnitzer, M., J.A. Ripmeester, and H. Kodama. 1988. Characterization of the organic matter associated with a soil clay.Soil Sci 145: 448–454CrossRefGoogle Scholar
  178. Schulten, H.R., and M. Schnitzer. 1990. Aliphatics in soil organic matter in fine-clay fractions.Soil Sci. Soc. Amer. J 54: 98–105CrossRefGoogle Scholar
  179. Seech, A.G., and E.G. Beauchamp. 1988. Denitrification in soil aggregates of different sizes.Soil Sci. Soc. Amer. J 52: 1616–1621CrossRefGoogle Scholar
  180. Shaymukhametov, M.S., N.A. Titova, L.S. Travnikova, and Y.M. Labenets. 1985. Use of physical fractionation methods to characterize soil organic matter.Soviet Soil Sci 16: 117–128Google Scholar
  181. Shiel, R.S. 1986. Variation in amounts of carbon and nitrogen associated with particle size fractions of soils from the Palace Leas meadow hay plots.J. Soil Sci 37: 249–257CrossRefGoogle Scholar
  182. Skjemstad, J.O., and R.C. Dalal. 1987. Spectroscopic and chemical differences in organic matter of two Vertisols subjected to long periods of cultivation.Aust. J. Soil Res 25: 323–335CrossRefGoogle Scholar
  183. Skjemstad, J.O., R.C. Dalal, and P.F. Barron. 1986. Spectroscopic investigations of cultivation effects on organic matter of Vertisols.Soil Sci. Soc. Amer. J 50: 354–359CrossRefGoogle Scholar
  184. Skjemstad, J.O., R.P. Le Feuvre, and R.E. Prebble. 1990. Turnover of soil organic matter under pasture as determined by 13C natural abundance.Aust. J. Soil Res 28: 267–276CrossRefGoogle Scholar
  185. Sollins, P., G. Spycher, and C.A. Glassman. 1984. Net nitrogen mineralization from light- and heavy-fraction forest soil organic matter.Soil Biol. Biochem 16: 31–37CrossRefGoogle Scholar
  186. Somasiri, S., S.Y. Lee, and P.M. Huang. 1971. Influence of certain pedogenic factors on potassium reserves of selected Canadian Prairie soils.Soil Sci. Soc. Amer. Proc 35: 500–505CrossRefGoogle Scholar
  187. Spycher, G., and J.L. Young. 1977. Density fractionation of water-dispersible soil organic-mineral particles.Commun. Soil Sci. Plant Anal 8: 37–48CrossRefGoogle Scholar
  188. Spycher, G., and J.L. Young. 1979. Water-dispersible soil organic-mineral particles: II. Inorganic amorphous and crystalline phases in density fractions of clay-size particles.Soil Sci. Soc. Amer. J 43: 328–332CrossRefGoogle Scholar
  189. Spycher, G., P. Sollins, and S. Rose. 1983. Carbon and nitrogen in the light fraction of a forest soil: Vertical distribution and seasonal patterns.Soil Sci 135: 79–87CrossRefGoogle Scholar
  190. Stevenson, F.J. E.T. Elliott, C.V. Cole, J. Ingram, J.M. Oades, C. Preston, P.J. Sollins. 1989. Methodologies for assessing the quantity and quality of soil organic matter, pp. 173–199. In D.C. Coleman, J.M. Oades, G. Uehara (eds.)Dynamics of Soil Organic Matter in Tropical Ecosystems NifTAL Project, University of Hawaii at Manoa, USA.Google Scholar
  191. Stevenson, I.L. 1958. The effect of sonic vibration on the bacterial plate count of soil.Plant Soil10 : 1–8CrossRefGoogle Scholar
  192. Stotzky, G 1986. Influence of soil mineral colloids on metabolic processes, growth, adhesion, and ecology of microbes and viruses, pp. 305–428. In P.M. Huang, M. Schnitzer (eds.)Interactions of Soil Minerals with Natural Organics and Microbes SSSA Publ., Madison, WI, USAGoogle Scholar
  193. Stotzky, G., R.G. Burns. 1982. The soil environment: Clay-humus-microbe interactions, pp. 105–133. In R.G. Burns, J.H. Slater (eds.)Experimental Microbial Ecology Blackwell Sci. Publ., Oxford, UKGoogle Scholar
  194. Suslick, K.S. (ed.) 1988a.Ultrasound: Its Chemical, Physical and Biological Effects. VCH Publishers, Inc., New York, USAGoogle Scholar
  195. Suslick, K.S. 1988b. Homogeneous sonochemistry. pp. 123–163. In K.S. Suslick (ed.) Ultrasound: Its Chemical, Physical and Biological Effects.VCH Publishers, New York, USA.Google Scholar
  196. Suslick, K., and S. Doktycz. 1990. Sounding out new chemistry.New Scientist 3: 50–53Google Scholar
  197. Syers, J.K., R. Shah, and T.W. Walker. 1969. Fractionation of phosphorus in two alluvial soils and particle-size separates.Soil Sci 108: 283–289CrossRefGoogle Scholar
  198. Swift, M.J., O.W. Heal, and J.M. Anderson. 1979.Decomposition in Terrestial Ecosystems. Blackwell Sci. Publ., Oxford, UKGoogle Scholar
  199. Sørensen, L.H. 1967. Duration of amino acid metabolites formed in soils during decomposition of carbohydrates.Soil Sci 104: 234–241CrossRefGoogle Scholar
  200. Sørensen, L.H. 1972. Stabilization of newly formed amino acid metabolites in soil by clay minerals.Soil Sci 114: 5–11CrossRefGoogle Scholar
  201. Sørensen, L.H. 1975. The influence of clay on the rate of decay of amino acid metabolites synthesized in soils during decomposition of cellulose.Soil Biol. Biochem 7: 171–177CrossRefGoogle Scholar
  202. Sørensen, L.H. 1981. Carbon-nitrogen relationships during the humification of cellulose in soils containing different amounts of clay.Soil Biol. Biochem 13: 313–321CrossRefGoogle Scholar
  203. Sørensen, L.H. 1983. Size and persistence of the microbial biomass formed during the humification of glucose, hemicellulose, cellulose, and straw in soils containing different amounts of clay.Plant Soil 75: 121–130CrossRefGoogle Scholar
  204. Sørensen, L.H. 1987. Organic matter and microbial biomass in a soil incubated in the field for 20 years with14C-labelled barley straw.Soil Biol. Biochem 19: 39–42CrossRefGoogle Scholar
  205. Tan, K.H., and P.S. Troth. 1981. Increasing sensitivity of organic matter and nitrogen analysis using soil separates.Soil Sci. Soc. Am. J 45: 574–577CrossRefGoogle Scholar
  206. Tanner, C.B., and M.L. Jackson. 1947. Nomographs of sedimentation times for soil particles under gravity or centrifugal acceleration.Soil Sci. Soc. Amer. Proc 12: 60–65CrossRefGoogle Scholar
  207. Tate, K.R., and G.J. Churchman. 1978. Organo-mineral fractions of a climosequence of soils in New Zealand tussock grasslands.J. Soil Sci 29: 331–339CrossRefGoogle Scholar
  208. Theng, B.K.G., G.J. Churchman, and R.H. Newman. 1986. The occurrence of interlayer clay-organic complexes in two New Zealand soils.Soil Sci 142: 262–266CrossRefGoogle Scholar
  209. Theodorou, C. 1990. Nitrogen transformations in particle size fractions from a second rotation pine forest soil.Commun. Soil Sci. Plant Anal 21: 407–413CrossRefGoogle Scholar
  210. Thorburn, P.J., and R.J. Shaw. 1987. Effects of different dispersion and fine- fraction determination methods on the results of routine particle-size analysis.Aust. J. Soil Res 25: 347–360CrossRefGoogle Scholar
  211. Tiessen, H., and J.W.B. Stewart. 1983. Particle-size fractions and their use in studies of soil organic matter: II. Cultivation effects on organic matter composition in size fractions.Soil Sci. Soc. Amer. J 47: 509–514CrossRefGoogle Scholar
  212. Tiessen, H., and J.W.B. Stewart. 1988. Light and electron microscopy of stained microaggregates: the role of organic matter and microbes in soil aggregation.Biogeochemistry 5: 312–322CrossRefGoogle Scholar
  213. Tiessen, H., J.W.B. Stewart, and J.O. Moir. 1983. Changes in organic and inorganic phosphorus composition of two grassland soils and their particle size fractions during 60–90 years of cultivation.J. Soil Sci 34: 815–823CrossRefGoogle Scholar
  214. Tiessen, H., R.E. Karamanos, J.W.B. Stewart, and F. Selles. 1984a. Natural nitrogen-15 abundance as an indicator of soil organic matter transformation in native and cultivated soils.Soil Sci. Soc. Amer. J 48: 312–315CrossRefGoogle Scholar
  215. Tiessen, H., J.W.B. Stewart and H.W. Hunt. 1984b. Concepts of soil organic matter transformations in relation to organo-mineral particle size fractions.Plant Soil 76: 287–295CrossRefGoogle Scholar
  216. Tinsley, J., J.F. Darbyshire (eds.) 1984. Biological Processes and Soil Fertility. Martinus Nijhoff/Dr. W. Junk Publ. The Hague, The NetherlandsGoogle Scholar
  217. Tisdall, J.M., and J.M. Oades. 1982. Organic matter and water-stable aggregates in soils.J. Soil Sci 33: 141–163CrossRefGoogle Scholar
  218. Tsutsuki, K., and S. Kuwatsuka. 1989. Degration and stabilization of the humus in buried humic Ando soils.Sci. Tot. Environ 81/82, 437–446Google Scholar
  219. Turchenek, L.W., and J.M. Oades. 1974. Size and density fractionation of naturally occurring organo-mineral complexes.Trans. 10th Int. Congr. Soil Sci., Moscow 2: 65–72Google Scholar
  220. Turchenek, L.W., J.M. Oades. 1978. Organo-mineral particles in soils. pp. 138–144. In W.W. Emerson et al. (eds.)Modification of Soil Structure. Wiley, ChichesterGoogle Scholar
  221. Turchenek, L.W., and J.M. Oades. 1979. Fractionation of organo-mineral complexes by sedimentation and density techniques.Geoderma 21: 311–343CrossRefGoogle Scholar
  222. Van der Linden, A.M.A., J.A. Van Veen, M.J. Frissel. 1987. Modelling soil organic matter levels after long-term applications of crop residues, and farmyard and green manures.Plant Soil 101:21–28.CrossRefGoogle Scholar
  223. Van Veen, J. A., P.J. Kuikman. 1990. Soil structural aspects of decomposition of organic matter by micro-organisms.Biogeochemistry 11: 213–234CrossRefGoogle Scholar
  224. Van Veen, J.A., E.A. Paul. 1981. Organic carbon dynamics in grassland soils. 1. Background information and computer simulation.Can. J. Soil Sci 61: 185–201CrossRefGoogle Scholar
  225. Van Veen, J.A., J.N. Ladd, M. Amato. 1985. Turnover of carbon and nitrogen through the microbial biomass in a sandy loam and a clay soil incubated with [14C (U)] glucose and [15N] (NH4)2SO4 under different moisture regimes.Soil Biol. Biochem 17: 747–756CrossRefGoogle Scholar
  226. Vaughan, D., R.E. Malcolm (eds.) 1985.Soil Organic Matter and Biological Activity Martinus Nijhoff/Dr. W. Junk Publ., Dordrecht, The NetherlandsGoogle Scholar
  227. Verberne, E.L.J., J. Hassink, P. de Willigen, J.J.R. Groot, J.A. van Veen. 1990. Modelling organic matter dynamics in different soils.Neth. J. Agric. Sci 38:221–238Google Scholar
  228. Vitorello, V.A., C.C. Cerri, F. Andreux, C. Feller, and R.L. Victoria. 1989. Organic matter and natural carbon-13 distribution in forested and cultivated oxisols.Soil Sci. Soc. Amer. J 53: 773–778CrossRefGoogle Scholar
  229. Voroney, R.P., E.A. Paul, and D.W. Anderson. 1989. Decomposition of wheat straw and stabilization of microbial products.Can. J. Soil Sci 69: 63–77CrossRefGoogle Scholar
  230. Walker, P.H., and J. Hutka. 1973. Grain fragmentation in preparing samples for particle-size analysis.Soil Sci. Soc. Amer. Proc 37: 278–280CrossRefGoogle Scholar
  231. Wang, T.S.C., S.W. Li, and Y.L. Ferng. 1978. Catalytic polymerization of phenolic compounds by clay minerals.Soil Sci 126: 15–21CrossRefGoogle Scholar
  232. Wang, T.S.C., M.C. Wang, and Y.L. Ferng. 1983. Catalytic synthesis of humic substances by natural clays, silts and soils.Soil Sci 135: 350–360CrossRefGoogle Scholar
  233. Wang, T.S.C., P.M. Huang, C.-H. Chou, J.-H. Chen. 1986. The role of soil minerals in the abiotic polymerization of phenolic compounds and formation of humic substances, pp. 251–281. In P.M. Huang M. Schnitzer (eds.), Interactions of Soil Minerals with Natural Organics and Microbes SSSA, Madison, Wisconsin, USAGoogle Scholar
  234. Watson, J.R. 1970.Studies on clay-organic nitrogen complexes in soils Ph.D. thesis, Department of Soil Science, University of Aberdeen, UKGoogle Scholar
  235. Watson, J.R. 1971. Ultrasonic vibration as a method of soil dispersion.Soils Fert 34: 127–134Google Scholar
  236. Watson, J.R., and J.W. Parsons. 1974a. Studies of soil organo-mineral fractions. Isolation by ultrasonic dispersion.J. Soil Sci 25: 1–8CrossRefGoogle Scholar
  237. Watson, J.R., and J.W. Parsons. 1974b. Studies of soil organo-mineral fractions. Extraction and characterization of organic nitrogen compounds.J. Soil Sci 25: 9–15CrossRefGoogle Scholar
  238. Weissler, A., and E.J. Hine. 1962. Variations of cavitation intensity in an ultrasonic generator.J. Acoust. Soc. Amer 34: 130–131CrossRefGoogle Scholar
  239. Whitehead, D.C., H. Buchan, R.D. Hartley. 1975. Components of soil organic matter under grass and arable cropping.Soil Biol. Biochem 7: 65– 71CrossRefGoogle Scholar
  240. Williams, B.L. 1983. The nitrogen content of particle size fractions separated from peat and its rate of mineralization during incubation.J. Soil Sci 34: 113–125CrossRefGoogle Scholar
  241. Williams, B.L., M.V. Cheshire, and G.P. Sparling. 1987. Distribution ofl4C between particle size fractions and carbohydrates separated from a peat incubated withl4C-glycine.J. Soil Sci 38: 659–666CrossRefGoogle Scholar
  242. Young, J.L., and G. Spycher. 1979. Water-dispersible soil organic-mineral particles: I. Carbon and nitrogen distribution.Soil Sci. Soc. Amer. J 43: 324–328CrossRefGoogle Scholar
  243. Zhang, H., M.L. Thompson, and J.A. Sandor. 1988. Compositional differences in organic matter among cultivated and uncultivated Argiudolls and Hapludalfs derived from loess.Soil Sci. Soc. Amer. J. 52: 216–222CrossRefGoogle Scholar
  244. Zhu, Y., G. Pardini, G. Poggio, and P. Sequi. 1983. Distribution of phosphorus in particle-size fractions of soils treated with organic wastes.Agrochimica 27: 105–111Google Scholar

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