Gleyed soils

Brammer H, Brinkman R. 1977. Surface-water gley soils in Bangladesh environment, landforms and soil morphology. Geoderma 17 19-109. 

Brinkman R. 1977b. Surface-water Gley soils in Bangladesh. Genesis. Geoderma 17 111-144. 

A.S. Cutler E.J.B. (1985) Distribution of elements in some Fe-Mn nodules and an iron-pan in some gley soils of New Zealand. Geoderma 35 127-143... 

Plate 16.1 e) Root channel in a gley soil stained by Fe oxide, f) Bleaching of the surface layer of a red soil aggregate by microbial reduction of the hematite. See root mat at the aggregate s surface supplying the biomass. 

Gley. Soil developed under reducing conditions as a result of poor drainage, characterized by a gray and mottled coloration. 

The excessive ground humidity is favorable to tbe formation of gley soils in Boreal forest ecosystems. Clay-podzolic soils with a massive forest litter layer provide the conditions for low water saturation. In high water-saturated conditions, a peat horizon... 

In A horizons, some Fe and Mn can also be precipitated around plant roots. In many wetland plants, reddish-brown layers are seen around the roots, as a result of Fe oxidation and subsequent precipitation. This can also result in mottle formation along the channels of plant roots with surrounding gleyed soil. Root zone oxidation is most visible in completely reduced and gleyed soils, where they appear on red to yellow mottles. 

Used with B or C horizon g Gleyed or waterlogged soil... 

Iron in the ferrous state is more soluble than iron in the ferric state. Indeed, in the ferric state, it is insoluble under most soil conditions. Under reducing conditions, ferrous iron may be leached out of soil, leaving it gray in color. This is the origin of the term gleying. 

The color of soil gives an indication of its oxidation-reduction conditions and the amount of OM present. Well-aerated soils will be under oxidizing conditions iron will be in the Fe3+ state, less soluble and thus less available for chemical reaction. Under water-saturated conditions, soil will be under reducing conditions as indicated by increased yellow colorings, gleying, and mottling. Iron will be in the Fe2+ state, which is more soluble and thus more available for chemical reaction. Under these conditions, reduced species such as methane (CH4), hydrogen, (H2), and sulfides will be found. 

Bloomfield C. 1951. Experiments on the mechanism of gley formation. Journal of Soil Science 2 196-211. 

Ottow ICG. 1973. Bacterial mechanism of iron reduction and gley formation. In Schlicht-ing E, Schwertmann U, eds. Pseudogley and Gley. Weinheim International Soil Science Society, 29-35. 

Groundwater and stagnant water soils (gleys and pseudogleys) and podzols of temperate and cool regions. Paddy soils. 

Schwertmann, U. (eds.) Pseudogley and gley. Trans. Comm. V VI Int. Soil Sci. Soc., VCH.Weinheim, 37-44 Fischer, W.R. (1976) Differenzierung oxalatlosli-cher Eisenoxide. Z. Pflanzenernahr. Bodenk. 

Schwertmann, U. Taylor, R.M. (1973) The in vitro transformation of soil lepidocrocite to goethite. Pseudogley Gley, Trans. Comm. V VI Int. Soc. Soil Sd. Stuttgart-Hohenheim 1971 45-54... 

Fig. 1. Hypothetical soil profile chat has all principal horizons. Not all horizons shown are present in any given profile, but every profile has some of them. Terms used in diagram Eluviation is the downward movement of soluble or suspended material in a soil from the A horizon to the B horizon by groundwater percolation. The term refers especially, but not exclusively, lo the movement of colloids, whereas the term leaching refers lo the complete removal of soluble materials. Illuviation is the accumulation of soluble or suspended material in a lower soil horizon that was transported from an upper horizon by the process of eluviation. Gleying is soil mottling, caused by partial oxidation and reduction of its constituent ferric iron compounds, due to conditions of intermittent water saturation. Process is also called gleizalion (Adapted from USD A diagram)...

Soil orders Alf, alfisol And, andisol Cam, cambisol Gley, gleysol Hist, histosol Inc, inceptisol Moll, mollisol Ox, oxisol Spod, spodosol Ult, ultisol. 

Gley horizons form when the water table is present within the soil profile. Soils with gley horizons (denoted g ) are typically aquepts (gleysols), a suborder of the inceptisols (Fig. 4.22). Gley horizons may be either Bg and/or Ag horizons, depending on the height of the water table influence in the soil profile (Fig. 4.25). 

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