Degradation of Argillic Horizons in Udalf Soils of New York State
1974
Bullock, P. | Milford, M. H. | Cline, M. G.
Interfingering of albic material into the upper part of argillic horizons in Udalfs of New York is interpreted as evidence of degradation by loss of clay proceeding from the top of the horizon downward and from the surfaces of peds inward. These conclusions are based on: (i) albic material lacking oriented clay surrounding ped centers that contain oriented clay; (ii) the volume of albic material decreasing with depth; and (iii) the albic interfingering being least in soils in which high carbonate content is believed to have delayed clay translocation or weathering. The absence of clay skins in the degrading zone—in contrast with thick clay skins rich in fine clay at the Bt-C horizon boundary—suggests that part of the clay removed at the top is translocated to the bottom of the B horizon. Smaller amounts of inherited mica clays and larger amounts of vermiculite, intergradient clays, and amorphous material in the clay fractions of degraded zones than in the remainder of B horizons indicates some weathering, but losses by this mechanism are believed small.
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