Fate and efficacy of polyacrylamide applied in furrow irrigation: Full-advance and continuous treatments

Destino y Eficacia del Poliacrilamido Aplicado en irrigación en Surcos: Tratamientos Avanzados y Continuos-Completos

Lentz, Rodrick D. and Sojka, Robert E. and Mackey, Bruce E. (2002) Fate and efficacy of polyacrylamide applied in furrow irrigation: Full-advance and continuous treatments. Journal of Environmental Quality. 31:661-670.

	PDF ES_1062.pdf Download (12kB)
	PDF 1062.pdf Download (355kB)

Abstract

Polyacrylamide (PAM) is applied to 400 000 irrigated hectares
annually in the USA to control irrigation-induced erosion, yet the
fate of dissolved PAM applied in irrigation water is not well documented. We determined the fate of PAM added to furrow streams
under two treatments: Initial-10, 10 mg L-1 PAM product applied
only during the initial hours of the irrigation, and Cont-1, 1.0 mg L—1
PAM product applied continuously during the entire irrigation. The
study measured PAM concentrations in 167-m-long PAM-treated
furrow streams and along a 530-m tail ditch that received this runoff.
Soil was Portneuf silt loam (coarse-silty, mixed, superactive, mesic
Durinodic Xeric Haplocalcid) with 1.5% slope. Samples were taken
at three times during the irrigations, both during and after PAM
application. Polyacrylamide was adsorbed to soil and removed from
solution as the streams traversed the soil-lined channels. The removal
rate increased with stream sediment concentration. Stream sediment
concentrations were higher when PAM concentrations were <2 mg
L-1 a.i., for early irrigations, and when untreated tributary flows combined with the stream. In these cases, PAM concentration decreased
to undetectable levels over the flow lengths used in this study. When
inflows contained >6 mg L-1 PAM a.i., stream sediment concentrations were minimal and PAM concentrations did not change down
the furrow, though they decreased to undetectable levels within 0.5
h after application ceased. One percent of applied PAM was lost in
tail-ditch runoff. This loss could have been eliminated by treating
only the furrow advance or not treating the last two irrigations.

Item Type:	Article
NWISRL Publication Number:	1062
Subjects:	Polyacrylamide (PAM) > Water-soluble PAM (WSPAM) Mass Import - autoclassified (may be erroneous)
Depositing User:	Users 6 not found.
Date Deposited:	18 Jun 2009 15:53
Last Modified:	14 Nov 2016 16:00
Item ID:	134
URI:	https://eprints.nwisrl.ars.usda.gov/id/eprint/134