Trade-off between runoff and sediments from treated erosion plots and polyacrylamide and acrylamide residues

The present study aimed to evaluate the quantitative effect of polyacrylamide (PAM) on runoff and soil loss, and the amount of PAM polymer and acrylamide (AMD) monomer emissions from experimental plots under laboratory conditions. The different levels of treatment of 0, 0.4, 0.6, 1, 2, 3, 4, and 6gm−2 PAM were applied to small plots of 0.05m2 installed in the Rainfall and Soil Erosion Simulation Laboratory of Tarbiat Modares University, Iran, with a simulated rainfall intensity of 72mmh−1, duration of 0.5h, and slope of 20% (i.e., 11.5°) applied to a silty loam, similar to that for real conditions. To determine the optimal level of PAM application for soil and water conservation under laboratory condition, PAM polymer and AMD monomer were measured in outing runoff and sediment. An analytical technique based on a spectrophotometer was developed to quantify the amount of PAM polymer present; the determination of amide groups by the NBM was also formulated for the quantification of PAM polymer. The background AMD concentrations in runoff and sediment were determined using the EPA method 8032A in triplicate. The analysis of AMD was performed on a gas chromatograph system equipped with an electron capture detector and Clarity 4.2 Data Acquisition software. The results proved a significant PAM polymer emission in runoff and sediment (P