Genesis of Red and Black Soils on Basalt on the Darling Downs, Queensland, Australia

Abstract

Shallow friable red soils (euchrozems) and shallow cracking clays (black earths) occur in close proximity on basalt hills of the Darling Downs of Queensland. The euchrozems are mainly restricted to fiat hill crests and are associated with lithosols; the shallow black earths occur on upper pediment slopes, on small convex crests and on depressions on flat crests. The euchrozems are moderately leached and contain kaolin minerals and hematite with minor montmorillonite, while the black earths are dominantly montmorillonite with minor kaolin and hematite. It is proposed that the euchrozems have developed by long continued weathering under stable well-drained conditions while the black earths have formed in sites prone to erosion and in situations with less water available for weathering. The weathering products produced in each situation have ensured continuation of the processes. The presence of two red soils in anomalous positions have been ascribed to (a) soil formation on exposed 'bole' (compacted red clay) layers and (b) local peculiarities of parent material controlling the course of weathering.

Reuse potential of laundry greywater for irrigation based on growth, water and nutrient use of tomato

“…The soil at the experimental site is a moderately deep, well structured Red Ferrosol (Isbell, 1996) that is a fertile soil distributed throughout Australia and developed from olivine basalt of lower Miocene age containing kaolinite and hematite with small amounts of montmorillonite clays (Beckmann et al, 1974). Sufficient soil (approx.…”

The geochemistry of soils on a catena on basalt at Khon Buri, northeast Thailand

“…The smectite contains a higher concentration of SiO 2 than does kaolin, and the octahedral cation site of smectite is occupied by Mg and Fe, in addition to Al, thus further reducing the Al 2 O 3 concentration (Borchardt, 1977;Birkeland, 1999). Very small quartz grains are abundant in all four soils and although quartz is not a primary mineral in basalt, Beckmann et al (1974) proposed that it could be a product of weathering or geological alteration. Alternatively it could have been deposited onto the soils as aeolian sediment (Prone, 2003) and incorporated throughout the profiles by pedoturbation.…”

“…All soils in this catena have high clay contents (N 500 g kg − 1 ) with increasing concentrations of clay with depth which indicates that translocation of clay from the A-horizon to B-horizon has taken place. The elevated concentrations of clay in the B-horizon are also a result of the high degree of transformation of primary minerals to clay minerals (Beckmann et al, 1974). All soils follow the general trend of having the highest organic matter content in the surface.…”

“…For an Oxisol catena developed on a veneer of sediment underlain by basalt in Brazil, the soils on an upper slope position had relatively high hematite and gibbsite contents and those on a lower position had relatively high goethite and kaolin contents, because soils on the upper slope position were both more leached and relatively drier than those on the lower slope position (Curi and Franzeier, 1984). Generally, kaolin occurs in upslope soils whereas smectite is present only in depressions and deep subsoils in mature soils on basaltic terrains (Kantor and Schwertmann, 1974;Beckmann et al, 1974;Fitzpatrick and Le Roux, 1977). Bhattacharyya et al (1992) studied the transformation of minerals in a basaltic soil catena in India.…”

“…Catenary soil sequences derived from basalt have been studied widely (Yaalon et al, 1971;Kantor and Schwertmann, 1974;Beckmann et al, 1974;Fitzpatrick and Le Roux, 1977;Herbillon et al, 1981;Curi and Franzeier, 1984;Webb and Dowling, 1990;Bhattacharyya et al, 1992;Weitkamp et al, 1996;Righi et al, 1999). The spatial distributions of minerals and elements in soils formed from basalt are partly controlled by topographic position, especially in tropical regions (Yaalon et al, 1971;Kantor and Schwertmann, 1974;Fitzpatrick and Le Roux, 1977;Curi and Franzeier, 1984;Bhattacharyya et al, 1992;dos Anjos et al, 1995).…”