Global InformationCheluviation information
Cheluviation is the process in which the metal ions in the upper layer of the soil are combined with organic ligands to form coordination complexes or chelates, moving downwards through eluviation and then depositing.[1]
Metal ions that can participate in chelation include Fe, Al, Mn, Ca, Mg and trace elements in soil, while the organic ligands combined with these metal ions come mainly from the soil organic matter. Soil organic matter includes relatively stable complex organic compounds (such as lignin, protein, humus, etc.), as well as some simple organic acids and intermediate products of microbial decomposition of organic matter.[2] These organic coordination compounds all contain active groups to varying degrees. Chain organic coordination compounds are complexed with metal ions to generate complexes, and these generated complexes containing multiple coordination atoms in a cyclic structure with metal ions are called chelates.[3][4] The stability of the chelate is related to the number of atoms in the chelate ring, the stability constant of the chelation reaction, and the concentration of organic chelating agents and metal ions.[5][6] The chelates produced by fulvic acid and metal ions in soil humus have strong leaching and deposition effects, and therefore are an important manifestation of soil cheluviation, which is generally resulting in the formation of gray-white leaching layers and dark brown/red deposited layer.[7]
- ^ Van Ranst, E.; De Coninck, F. (2002). "Evaluation of ferrolysis in soil formation". European Journal of Soil Science. 53 (4): 513–520. doi:10.1046/j.1365-2389.2002.00475.x. S2CID 247661307.
- ^ Brady, Nyle C (1984). The Nature and Properties of Soils (Ninth ed.). New York, USA: MacMillan. p. 254. ISBN 0-02-313340-6.
{{cite book}}: CS1 maint: location missing publisher (link) - ^ Frausto Da Silva, J. J. R. (1983). "The chelate effect redefined". Journal of Chemical Education. 60 (5): 390. Bibcode:1983JChEd..60..390F. doi:10.1021/ed060p390.
- ^ Stevenson, F. J. (1991). "Organic Matter-Micronutrient Reactions in Soil". Micronutrients in Agriculture. SSSA Book Series. Vol. 4. pp. 145–186. doi:10.2136/sssabookser4.2ed.c6. ISBN 9780891188780. S2CID 93494971.
- ^ Calvin, M.; Wilson, K. W. (1945). "Stability of chelate compounds". Journal of the American Chemical Society. 67 (11): 2003–2007. doi:10.1021/ja01227a043.
- ^ Calvin, Melvin; Melchior, Norten C. (1948). "Stability of Chelate Compounds. IV. Effect of the Metal Ion1". Journal of the American Chemical Society. 70 (10): 3270–3273. doi:10.1021/ja01190a020. PMID 18891839.
- ^ Jarukas, Laurynas; Ivanauskas, Liudas; Kasparaviciene, Giedre; Baranauskaite, Juste; Marksa, Mindaugas; Bernatoniene, Jurga (2021). "Determination of organic compounds, fulvic acid, humic acid, and humin in peat and sapropel alkaline extracts". Molecules. 26 (10): 2995. doi:10.3390/molecules26102995. PMC 8157823. PMID 34069989.