The assessment of physicochemical factors influencing phosphorus mineralization and immobilization in an Illinois floodplain soil
type: CreativeWork
description: Persistent losses of phosphorus (P) from soil to aquatic environments, provoked by human activity, degrade downstream water quality. Thus, it is critical to gain a deeper understanding of the biogeochemical processes that govern P bioavailability/mobility in the soil, including P mineralization and immobilization. Through microbially mediated immobilization, inorganic P is transformed into an organic form while during mineralization, organic P is converted into a labile, inorganic form, which is more susceptible to loss. In this study, the occurrence of mineralization/immobilization in Illinois floodplain soils was thoroughly examined. First, a comprehensive examination of mineralization and immobilization parameters in a floodplain and its adjacent upland was carried out. Due to higher total organic P and microbial P relative to the upland soil, it was concluded that the floodplain soil buffers P in part through microbial immobilization (Chapter 2). However, the degree of P immobilization varied throughout the floodplain, which motivated further investigation of physicochemical parameters that may be influencing the process, namely organic C and inorganic N. The following objectives were subsequently developed: 1) to evaluate the influence of native leaf residue on P reaction dynamics as a function of the C composition of the residue and the soil organic C:P ratio and 2) to investigate if the P mineralization rates vary as a function of inorganic nitrogen (N) species. Separately, floodplain soils were amended with 1) three species of native leaf residue with varying C compositions and 2) nitrate (NO3-N) and ammonium (NH4-N). Phosphorus mineralization/immobilization dynamics (i.e., wet chemistry analysis and NMR spectroscopy) were examined during long-term laboratory incubations. In the C study, residues with low aromaticity promoted P mineralization, and residues with high aromaticity and hydrophobicity led to P immobilization (Chapter 3). In the N study, NH4-N was…
abstract: Persistent losses of phosphorus (P) from soil to aquatic environments, provoked by human activity, degrade downstream water quality. Thus, it is critical to gain a deeper understanding of the biogeochemical processes that govern P bioavailability/mobility in the soil, including P mineralization and immobilization. Through microbially mediated immobilization, inorganic P is transformed into an organic form while during mineralization, organic P is converted into a labile, inorganic form, which is more susceptible to loss. In this study, the occurrence of mineralization/immobilization in Illinois floodplain soils was thoroughly examined. First, a comprehensive examination of mineralization and immobilization parameters in a floodplain and its adjacent upland was carried out. Due to higher total organic P and microbial P relative to the upland soil, it was concluded that the floodplain soil buffers P in part through microbial immobilization (Chapter 2). However, the degree of P immobilization varied throughout the floodplain, which motivated further investigation of physicochemical parameters that may be influencing the process, namely organic C and inorganic N. The following objectives were subsequently developed: 1) to evaluate the influence of native leaf residue on P reaction dynamics as a function of the C composition of the residue and the soil organic C:P ratio and 2) to investigate if the P mineralization rates vary as a function of inorganic nitrogen (N) species. Separately, floodplain soils were amended with 1) three species of native leaf residue with varying C compositions and 2) nitrate (NO3-N) and ammonium (NH4-N). Phosphorus mineralization/immobilization dynamics (i.e., wet chemistry analysis and NMR spectroscopy) were examined during long-term laboratory incubations. In the C study, residues with low aromaticity promoted P mineralization, and residues with high aromaticity and hydrophobicity led to P immobilization (Chapter 3). In the N study, NH4-N was…
author: Arenberg, Mary
language: en
keywords: Soil Chemistry, Nutrient Cycling, Biogeochemistry, Phosphorus, Mineralization
date published: 2021-09-17T04:03:59Z
date modified: 2026-07-22T22:24:52Z
provider: University of Illinois - Urbana-Champaign
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: University of Illinois at Urbana-Champaign

PropertyValue
property ID: Handle
value: http://hdl.handle.net/2142/110779