Morphogenesis of soils on two sandy marine terraces in northwest florida
1996
Goldin, A. | Collins, M. E. (Mary Elizabeth)
The objective of this research was to examine the effects of time and landscape position on the weathering and development of sandy soils in three topographic positions on Late-Pleistocene and Holocene age marine terraces in northwest Florida. The study examined three soils on the Silver Bluff marine terrace (Holocene surface) close to the Gulf of Mexico (<0.5 km) and three soils on the Pamlico marine terrace (Late-Pleistocene surface) approximately 1 km from the Gulf. A poorly drained, a moderately well drained, and an excessively drained pedon were studied on each surface. This sampling scheme resulted in a paired comparison of soils between surfaces for the three drainage classes examining the effects of time and topography (particularly, depth to water table) on organic carbon and total phosphorus (TP) contents, particle size, pH, extractable Fe and Al, and mineralogy. Results of the study indicate that the physical and chemical properties above were similar, but the morphologies were distinctly different. Similarities in particle size support a general uniformity of parent material, suggesting a homogeneous marine depositional environment. Organic carbon, pH, total P, and extractable Fe and Al did not show any trends with landscape position nor with age except those explained by morphological differences. As expected, the three soils sampled on the younger Silver Bluff terrace and closest to the Gulf of Mexico were Entisols with an ochric epipedon and no diagnostic subsurface horizons (A - C profiles). At the greater distance from the present shoreline, the older soils exhibited more morphological development: presence of a spodic (Bh) horizon or were Entisols with a colored Bw horizon.
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