Submitted to: Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: June 1, 1997
Publication Date: N/A
Technical Abstract: A new practice adds 10 ppm water-soluble anionic polyacrylamide (PAM) to initial irrigation inflows to control soil erosion and increase net infiltration in furrow irrigated fields. PAM's influence on soil water and solute movement is not well understood. We deployed percolation samplers and reflected-pulse multivibrator (RPM) soil water sensors in furrow-irrigated PAM-treated plots to test the hypothesis that PAM- management affects irrigation uniformity and organic and inorganic solute movement through the root zone. Twelve sites with three samplers each were established in control and PAM treatments at top and bottom locations in the field (Portneuf silt loam, Durixerollic Calciorthids, with 1.6% slope). Percolation samplers consisted of a 23-cm-deep, 20-cm-dia. stainless-steel beaker with a 17-cm-long, 4-cm-dia., 0.5 bar air-entry ceramic cup imbedded in a 5-cm-deep silica flour layer slurried into the beaker bottom. Water was collected under suction (~1.2x ambient) from teflon tubes. Nitrate, bromide, and alachlor concentrations and soil water flux, soil wetting patterns, and temperature were determined. Percolation sampler design and testing, field installation, study experimental design, and preliminary results will be presented.