Soil genesis along a chronosequence on marine terraces in eastern Taiwan
Journal
Catena
Journal Volume
71
Journal Issue
3
Pages
394-405
Date Issued
2007
Author(s)
Abstract
Soil chronosequences developed on elevated marine terraces are ideal for studying changes in soil-forming processes with time. The coastal range of eastern Taiwan is a product of active arc-continent collision. Vertisols, Mollisols and Entisols are generally found on the different levels of marine terraces herein, but no detailed investigations of soil chronosequence have been conducted by integrating field morphology, physio-chemical characterization, micromorphology and mass-balance interpretations. Five soil pedons were selected on the three marine terraces including Tt-1 and Tt-2 pedons (Typic Hapluderts) on the first higher level with the oldest soil age (9-10 ka), Tt-3 (Vertic Hapludolls) and Tt-4 pedons (Typic Hapludolls) on the second intermediate level (5-6 ka), and Tt-5 pedon (Typic Udipsamments) on the third lower level with the youngest soil age (≤ 3.5 ka). The morphological characteristics showed that strongly developed angular blocky structures, pressure faces and slickensides are more common in higher terrace soils than in lower terrace soils. In this study, depth to C horizon, solum thickness, and thickness of the clay-enriched zone increase with relative terrace age. Although only one to two profiles per terrace were characterized, the following soil analytical characterizations increase with time: the degree of sand grains weathering, pH (H2O), organic carbon, CEC, contents of Fed, Feo and Mnd. Based on X-ray diffraction analysis of the clay-size fraction, soils on all terraces have a mixed mineralogy. Mica, smectite, and kaolinite have slightly increased with increasing terrace age. Furthermore, the dominant processes identified with mass-balance analysis include loss of bases (Ca and Mg), iron, and clay with time. The soil properties, including analytical and mineralogical characterizations, which do not have notable changes with time are primarily due to relatively young soil age (< 10 ka). © 2007 Elsevier B.V. All rights reserved.
Subjects
Marine terrace; Mass balance; Mollisols; Soil chronosequence; Vertisols
SDGs
Other Subjects
chronosequence; clay mineral; mass balance; micromorphology; Mollisol; pedogenesis; pedon; pH; physicochemical property; slickenside; terrace; timescale; Vertisol; weathering; X-ray diffraction; Asia; Eurasia; Far East; Taiwan
Type
journal article