| 释义 |
oxic, a.|ˈɒksɪk|
[f. oxide n., oxygen + -ic.]
1. Soil Science. Applied to a subsurface mineral soil horizon more than 30 cm. thick that is characterized by the virtual absence of any weatherable materials and the presence of hydrated oxides of iron and aluminium, highly insoluble minerals such as quartz, and clays of the type in which single sheets of silica tetrahedra alternate with single sheets of alumina octahedra. Cf. Oxisol.
1960Soil Classification: 7th Approximation (U.S. Dept. Agric.) v. 53/1 The concept of the oxic horizon presented here is very tentative, as it has had little testing... The oxic horizon is one from which weathering has..removed or altered a large part of the silica that is combined with iron and aluminium, but not necessarily the quartz or 1:1 lattice clays. 1970P. M. Ahn W. African Soils (1974) vii. 221 The boundaries of the oxic horizon are usually gradual and diffuse, and the horizon shows no rock structure or very little. 1972Foth & Turk Fund. Soil Sci. (ed. 5) x. 262 All soils with oxic horizons belong to the Oxisol order. 1976D. Steila Geogr. Soils xi. 151 It is believed that the most extensive areal development of the oxic horizon may have taken place under paleo-climates of much higher rainfal.
2. [Back-formation from anoxic a.] Involving, characterized by, or related to the presence of oxygen.
1970Acta Radiologica: Therapy, Physics, Biol. IX. 257 The investigations..were conducted with the aim of comparing the reactions of different cell lines to oxic and anoxic roentgen radiation. 1972Radiation Bot. XII. 151 The damage produced by anoxic irradiation can be enhanced by O2, after irradiation, to give oxic damage. 1975Nature 26 June 740/2 We have measured in oxic and anoxic cells the yield of strand breakage on bacteriophage λ DNA superinfecting lysogenic bacteria. 1975Ibid. 4 Dec. 415/1 It is formed from phytol thermocatalytically in oxic conditions.
Hence oˈxicity, oxic condition.
1978Nature 16 Mar. 216/2 The available data suggest that the oxicity/anoxicity of the sediment and the water column affects the amount and nature of the organic matter incorporated into the sediment during deposition. |