ARS | Publication request: Effect of water logging conditions on solubility of soil nutrients

Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract
Publication Acceptance Date: June 25, 2008
Publication Date: N/A

Technical Abstract: The wide use of herbicides, fungicides, fertilizers, and soil amendments affect the rhizosphere biochemistry and ecology. Soils in the Midwest of the US tend to be saturated in the early spring when snow and ice melt, and frequent rain occurs. Saturated conditions also occur after heavy rainfall events in the summer and fall. Periodic flooding causes the soil to go trough oxidation and reduction cycles. Oxygen enters the soil system through oxygenated rainwater infiltration or by diffusion; after the soil is water logged the O2 supply is curtailed. Plants and microbes use all the O2, and soil system moves toward being anaerobic. Under these conditions soil nutrient losses are believed to change due to a modification of the soil solution Eh and pH. An experiment was designed in order to evaluate the change in solubility of soil nutrients, in a soil subjected to water logging. Four different treatments were evaluated: 1) Control, 2) Control + Glyphosate, 3) Control + Gypsum, and 4) Control + Glyphosate + Gypsum. The soil used was a Toronto-Millbrook complex (fine, silty, mesic Udollic Ochraqualf). Hourly readings of Eh were measured, while measurements of pH, CO2 partial pressure and concentrations of N, P, DOC, and redox-sensitive species were obtained for 1, 3, 7, and 14 days. The results of this research are important in understanding nutrient losses and improving water quality.