Kaolinization of Biotite as a Result of Coniferous and Deciduous Seedling Growth

Abstract

The rhizosphcric activity of coniferous and deciduous tree seedlings grown for a period of 13 months in sand cultures containing biotite (50 to 2/i) as the only source of K and Mg, effected the transformation of biotite to kaolinite. The identity of the kaolinite was established by means of X-ray diffraction and electron microscope analyses. The effectiveness of the seedlings in producing kaolinite from biotite was in the order: white cedar > hemlock > white pine > white spruce > red oak > hard maple [(Thuja occidentals) > (Tsuga canadensis) > (I'inus ' strobus L.) > (Picea glauca > (Quercus rubra L. (Q. borealis Mich, x.f.) > (Acer saccharum)}. The conditions prevailing in the cultures accelerated the hydrolytic process and removal of K, Mg, and Fe from biotite and their substitution by H 3 O causing kaolinization. Electron microscope data revealed the characteristic hexagonal crystals of kaolinite forming on the mica surfaces. Monterey pine (P. radiata) grown in sand cultures converted biotite to vermiculite. The formation of vermiculite rather than kaolinite was attributed to the presence of metal cations in the root remains added to the cultures at the outset of the experiment.

Ability of alfalfa (Medicago sativa L.) to take up potassium from different micaceous minerals and consequent vermiculitization

“…reported that the vermiculitization of phlogopite resulted from an exchange of interlayer K occurring as a consequence of the large depletion of K in close vicinity of the roots. Transformation of biotite and phlogopite to HIV or kaolinite has been also reported (Spyridakis et al 1967).…”

Laccaria bicolor S238N improves Scots pine mineral nutrition by increasing root nutrient uptake from soil minerals but does not increase mineral weathering

“…This means that biotite has mainly been dissolved by an incongruent phenomenon which corresponds to the partial transformation of biotite into vermiculite. Weathering of phyllosilicates into vermiculite is basically a cation-exchange process which can be accelerated by uptakes of K by plants (Spyridakis et al 1967;Boyle and Voigt 1973;Hinsinger et al 1992) and ECM fungi (Leyval and Berthelin 1991;Paris et al 1995;Glowa et al 2003).…”

Accumulation of Uranium in Granitic Soils Overlying the Mourne Mountains, County Down, Northern Ireland

“…Podzolization, which is paramount in the pedogenesis of the soils under study, can cause chemical weathering (23)(24)(25)(26). Clay transformation is enhanced by such factors as vegetation cover and microorganisms (27,28). Podzolization has been the subject of much research (29)(30)(31)(32)(33)(34) and podzolic soils are considered to be formed under acidic conditions only.…”