Soil organic matter transformation in Argentinian Hapludolls

authored by: Wolfgang Zech, Georg Guggenberger, Pablo Zalba, Norman Peinemann
Abstract: Distribution and transformation of SOM in an Argentinian Hapludoll under arable land use and afforested with Pinus radiata was investigated by a combined approach using particle-size fractionation, wet-chemical analysis and ¹³C NMR spectroscopy. The soils showed thick mollic A horizons and had high organic carbon (OC) contents even in the subsoil, clay-sized separates having the highest OC concentrations. Under pine, a thick forest floor was built up. CuO oxidation data indicated low transformation of lignin in the forest floor, but advanced oxidative decomposition in the mineral soil horizon. In contrast, non-cellulosic carbohydrates, appeared to be stabilized in the mineral soil horizon against mineralization. Humic acids extracted from the mineral soil horizons showed an extremely high aromaticity. We assume that this was due to the production of pyrogenic aromatic moieties (black carbon) as a result of frequent fires in this ecosystem. No clear profile differentiation with respect to SOM quality was obtained. Composition of SOM in the mineral soil appeared not yet influenced from land use.
External Organisation(s): University of Bayreuth
Universidad Nacional del Sur
Type: Article
Journal: Journal of Plant Nutrition and Soil Science
Volume: 160
Pages: 563-571
No. of pages: 9
ISSN: 1436-8730
Publication date: 1997
Publication status: Published
Peer reviewed: Yes
ASJC Scopus subject areas: Soil Science, Plant Science
Sustainable Development Goals: SDG 15 - Life on Land
Electronic version(s): https://doi.org/10.1002/jpln.19971600507 (Access: Closed)