Author
Lentz, Rodrick | |
Bjorneberg, David - Dave |
Submitted to: American Society of Agricultural Engineers Meetings Papers
Publication Type: Abstract Only Publication Acceptance Date: 12/10/2000 Publication Date: N/A Citation: N/A Interpretive Summary: Water soluble anionic polyacrylamide (PAM) is a highly effective erosion deterrent in furrow irrigation, but little is known about the effect of plant residue on PAM efficacy. We hypothesized that PAM's ability to control erosion would not be affected by the presence of plant residue in irrigation furrows. Treatments included furrows with 3.2 g/m and 10 g/m straw applications irrigated with PAM or untreated water, and conventionally irrigated furrows (no PAM and no straw). A 0.4-ha field (Durinodic Xeric Haplocalcids) with 1.5% slope was furrow irrigated five times. PAM was applied as a granular patch at the furrow inflow end (33 g or 1 kg active ingredient ha/1). When possible, irrigation inflows of 22 L/min were cutback to 15 after runoff began. For a given water treatment, straw amounts had no significant effect on irrigation furrow sediment loss or net infiltration. In the first two irrigations after straw application, straw alone reduced sediment loss 80% and straw + PAM reduced sediment loss 100%, compared to conventionally irrigated furrows. In the last three irrigations, both water treatments in straw- protected furrows reduced sediment losses equally: PAM + straw reduced losses by 100% and straw alone by 95%, relative to conventionally irrigated furrows. When compared to published data, the PAM + straw treatment produced greater and more consistent erosion control than did PAM-only treatments. PAM application with furrow mulching provided an additional increase in erosion control over straw alone, but only during the first irrigations after straw application. Technical Abstract: Water soluble anionic polyacrylamide (PAM) is a highly effective erosion deterrent in furrow irrigation, but little is known about the effect of plant residue on PAM efficacy. We hypothesized that PAM's ability to control erosion would not be affected by the presence of plant residue in irrigation furrows. Treatments included furrows with 3.2 g/m and 10 g/m straw applications irrigated with PAM or untreated water, and conventionally irrigated furrows (no PAM and no straw). A 0.4-ha field (Durinodic Xeric Haplocalcids) with 1.5% slope was furrow irrigated five times. PAM was applied as a granular patch at the furrow inflow end (33 g or 1 kg active ingredient ha/1). When possible, irrigation inflows of 22 L/min were cutback to 15 after runoff began. For a given water treatment, straw amounts had no significant effect on irrigation furrow sediment loss or net infiltration. In the first two irrigations after straw application, straw alone reduced sediment loss 80% and straw + PAM reduced sediment loss 100%, compared to conventionally irrigated furrows. In the last three irrigations, both water treatments in straw- protected furrows reduced sediment losses equally: PAM + straw reduced losses by 100% and straw alone by 95%, relative to conventionally irrigated furrows. When compared to published data, the PAM + straw treatment produced greater and more consistent erosion control than did PAM-only treatments. PAM application with furrow mulching provided an additional increase in erosion control over straw alone, but only during the first irrigations after straw application. |