C. K. Losche, R. J. McCracken, C. B. Davey1,2,3
1Professor of Soil Science
2Professor of Soil Science and Forestry, Dept. of Soil Science, North Carolina State Univ., Raleigh, N. C., respectively.
3Research Soil Scientist, North Central Forest Exp. Sta., Carbondale, Ill. (formerly Graduate Assistant, North Carolina State Univ.)
Tóm tắt
AbstractAt two locations in the southern Appalachian Mountains, soils at two slope positions on north‐ and south‐facing landscapes were described, sampled, and analyzed to determine the relative effect of slope aspect and position upon the differentiation of the parent rock into soil profiles. At the southwestern Virginia study area, the parent rocks are highly siliceous sandstone and siltstone, whereas, the parent rock in southwestern North Carolina is a granitic biotite gneiss.Soils developed from the siliceous parent material were very similar in morphological, physical, chemical, and mineralogical properties irrespective of aspect and slope position. In contrast, there was a high degree of soil profile differentiation at the two slope positions and on the two aspects in North Carolina. In addition to differences in morphological and physical properties, there are distinct differences in the clay mineral suites on opposing aspects. Kaolin and the pedogenic 2:1–2:2 intergrade minerals are predominant in the soils of the north‐facing landscapes, whereas, gibbsite is the major clay mineral in the soils of the south‐facing landscape.
