Premium
Aggregation of soil particles by iron oxides in various size fractions of soil B horizons
Author(s) -
BARBERIS E.,
MARSAN F. AJMONE,
BOERO V.,
ARDUINO E.
Publication year - 1991
Publication title -
journal of soil science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.244
H-Index - 111
eISSN - 1365-2389
pISSN - 0022-4588
DOI - 10.1111/j.1365-2389.1991.tb00100.x
Subject(s) - chemistry , particle size , soil science , environmental chemistry , mineralogy , environmental science
SUMMARY Quantitative relationships between aggregation of soil particles and the content of haematite and goethite were studied by removing iron oxides, with dithionitetrate‐bicarbonate (DCB) and oxalate reagents, from various sizes of soil separates which were stable to sodium hexametaphosphate, and then determining the particle‐size distribution. Significant quantitative relationships were found between DCB‐extractable oxides and particles obtained from the separates up to 20 pm, whereas oxalate‐extractable oxides were correlated only with < 0.2‐μm particles. Oxalate‐extractable oxides were observed to aggregate a greater quantity of fine clay and a larger surface area of particles per gram of oxide than DCB‐extractable oxides, A more efficient mechanism of aggregation was postulated for the oxalate‐extractable oxides than for the DCB‐extractable oxides. There were fewer aggregated particles in soils containing haematite and goethite than in soils containing only goethite. This was attributed to differences in pedoenvironment, rather than to a difference in the behaviour of the oxides. Although various clay minerals were identified in the soils studied, no preferential aggregation of any mineral was observed.