ABSTRACT
Abstract The effects of irrigation water-added polyacrylamide (PAM) on erosion control and infiltration were studied on a highly erodible Mediterranean soil organised on contour and on traditionally slopped furrows. Water added PAM significantly reduced sediment concentration and increased infiltration on the slopping ones. Obtained reductions on the contour site were less dramatic as cut back of initially high inflow rates and furrows implanted on a terrace of very mild slope helped to alleviate the differences between PAM treatment and the control. As for the infiltration, wateradded PAM in the slopped furrows avoided the slacking and seal formation observed in the wetted perimeter of the non treated ones, and helped to maintain infiltration rates higher for longer periods of the irrigation set. Cumulative infiltration was also improved, showing high percentage increases for all events. In spite of the visible improvement on aggregate stability of the soil, on contour furrows the infiltration results were not significantly different from control. Regular use of PAM in the irrigation water also helped to reduce fine particle movement in the furrows, preventing tailwater pollution with fine sediments. Keywords: Erosion, infiltration, polyacrylamide, sediment loss, soil particle movement, water quality.
