Monday, November 5, 2007
97-4
Iron Reduction and Phosphorus Solubilization in a Seasonally Wet Pasture Soil.
Jared Wilmoth and Louis M. McDonald. Plant & Soil Sciences, West Virginia University, PO Box 6108, Morgantown, WV 26506
Increased concentrations of soluble phosphorus (P) in flooded soils and sediments have been extensively observed, primarily as a consequence of ferric iron (Fe(III)) reduction. Lake sediments, soils flooded for rice production, and wetlands represent the biogeochemical models from which much of this evidence has accumulated. The goal of the research was to (1) characterize and quantify the Fe and P chemical transformations that are involved in and take place during Fe-P redox reactions in temperate pasture soils; (2) to compare the effects of AQDS (humic acid analog) on electron shuttling properties of these soils with the effects of extracted humic substances on electron shuttling properties of these soils; and (3) to collect continuous field-redox measurements at the sampling location. The overall goal of this research is to further understand Fe and P cycling in pasture soils, cycling that largely determines the chemical stability and biological development of these soils.