Correcting the classification of plinthic Ultisols on aged alluvial terraces in Taiwan. Issue 3 (3rd May 2020)

• Record Type: Journal Article
• Authors: Liu, Xiao-Nan; Hseu, Zeng-Yei; Chen, Zueng-Sang
• Is Part Of: Soil science and plant nutrition. Volume 66:Issue 3(2020)
• Page Start: 458
• Page End: 468
• Publication Date: 2020-05-03
• Subjects: Plinthite -- Ultisols -- rice-growing soil -- Soil Taxonomy; Soil science -- Periodicals; Plants -- Nutrition -- Periodicals; 631.4
• DOI: 10.1080/00380768.2020.1755206
• Languages: English
• ISSNs: 0038-0768

Abstract

ABSTRACT: Alternative saturation and reduction are frequent in the Ultisols on aged alluvial terraces in Taiwan, which forms various redoximorphic features (RMFs) that depend on a seasonally high water table and geographic positions. The abundance and distribution of RMFs in the soil profile are criteria for the classification categories of Plinthite in Soil Taxonomy. Thus, we proposed an empirical relationship existed between regional hydrology and RMFs for soil interpretation and management on these terraces. The hydrological and pedological parameters included plinthite volume proportion (PVP, %), average annual saturated time of the year in soil (AAST, %), and average annual reduced time of the year (AART, %), which corresponded to the category levels in Soil Taxonomy of 14 reference pedons from the literatures and 14 additional pedons selected for this work in the study area. The analyses indicated that the PVP, AAST, and AART values all considerably decreased as elevation increased in the domain of <40 m above sea level (a.s.l.) in the reference pedons. The PVP generally decreased with increasing elevation in the domain of ≤50 m a.s.l. with the highest PVP was in 25–30 m a.s.l. where the AAST and AART were of medium duration. The Plinthite that meets the criteria for the great group was mainly distributed in the domain of ≤30 m a.s.l., while the Plinthite that meets the criteria for the subgroup was in the domain of 30–50 m a.s.l., according to this quantification of hydrogeomorphological information. The RMFs-based correction of the classifications for soil mapping matched the actual distribution of soil taxonomy categories. However, the fluctuations of the seasonally high water table and the soil texture were the additional factors controlling the variation of RMFs and distribution of category levels on the terraces.