Polyacrylamide sprayed on soil surfaces can stabilize soil aggregates

Lehrsch, G.A. and Kincaid, D.C. and Lentz, R.D. (1996) Polyacrylamide sprayed on soil surfaces can stabilize soil aggregates. pp. 533-538. In: Proc. of Conf. 27. Erosion control technology … bringing it home. USA-WA-Seattle, 1996/02/27-03/01. Int. Erosion Control Assoc., Steamboat Springs, CO.

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Abstract

Vegetative cover protects soil surfaces and aggregates from erosion caused by the
impact of raindrops or sprinkler drops. On bare surfaces, drop impact and wetting causes soil
aggregates to slake, releasing aggregate fragments and/or primary particles that can obstruct
pores at the soil surface and form a depositional seal. The seal reduces infiltration which, in
turn, increases runoff and soil erosion. Polyacrylamide (PAM) applications, known to stabilize
surface soil in irrigated furrows, may effectively stabilize soil aggregates as well. This field
experiment evaluated the effects of spray-applied PAM and sprinkler droplet energy on
surface soil aggregate stability, measured before and after 31 mm of irrigation. A moderate
charge-density, anionic PAM at two nominal rates, 10 and 25 kg ha-1, was applied as a
sprayed solution to replicated plots of a Portneuf silt loam (coarse silty, mixed, mesic
Durixerollic Calciorthid) near Kimberly, Idaho, on 25 July, 1995. A linear-move irrigation
system, designed to deliver water to the soil surface at two droplet energy levels, 5 and 15
J kg-1, applied a total of 31 mm of water to the plots 7 and 10 days after treatment. Soil
samples (0 to 5 mm depth) were taken before and 72 hours after this water was applied.
Gravimetric water content and aggregate stability by wet sieving were measured on these
samples. Initially, PAM-treated aggregates visually appeared to resist breakdown under
sprinkler/drop impact better than non-treated aggregates. PAM applications at economic
rates increased aggregate stability when droplet energy was 5 J kg-1 but had no effect when
droplet energy was 15 J kg-1 .

Item Type:	Conference or Workshop Item (Paper)
NWISRL Publication Number:	0894
Subjects:	Polyacrylamide (PAM) > Water-soluble PAM (WSPAM) Soil Mass Import - autoclassified (may be erroneous)
Depositing User:	Users 6 not found.
Date Deposited:	20 Nov 2010 21:55
Last Modified:	22 Nov 2016 23:33
Item ID:	872
URI:	https://eprints.nwisrl.ars.usda.gov/id/eprint/872