Skip to main content

Freezing effects on aggregate stability of soils amended with lime and gypsum

Lehrsch, G.A. and Sojka, R.E. and Jolley, P.M. (1993) Freezing effects on aggregate stability of soils amended with lime and gypsum. In: Poesen, J.W.A. and Nearing, M.A., (eds.) Soil Surface Sealing and Crusting. Catena Supplement, No. 24. pp. 115-127. Catena Verlag, Germany. ISBN 3-923381-33-6

[img] PDF

Download (631kB)


Aggregate stability, which influences soil
response to raindrop impact and other
erosive forces, is affected by freezing. We
hypothesized that lime or gypsum added
at agriculturally feasible rates may act
as bonding agents to mitigate the effects
of freezing on the stability of aggregates
from different soils. Thus, the objectives
of the laboratory study were to
determine the effects of freeze-thaw cycles,
water content at freezing, and lime
and gypsum additions on the aggregate
stability of six soils differing in texture,
mineralogy, and organic matter. To all
samples but the control, either CaCO3
or CaSO4 - 2H2O was added at a rate
of either 0.2 or 1.0% by weight of oven-dry
soil. Field-moist aggregates were
vapor-wetted to either a low water content
(5-10% w/w) or a high water content
(25-30%), then frozen and thawed
either 0, 1, or 3 times in brass cylinders.
After thawing, they were vapor-wetted
to 0.30 g g-1 and their stability
was characterized by wet sieving. For all
soils, aggregate stability decreased significantly
with increasing water content
at freezing. When averaged over bonding
agents and addition rates, soils commonly

increased in stability, at times
significantly, after one freeze-thaw cycle.
Soils with clay contents of 20% or
more and organic matter contents over
3% were the most stable after freezing.
When averaged over soils and freeze
thaw cycles, aggregate stability was not
affected by bonding agents at low water
contents. At high water contents,
however, stability increased significantly
(P<0.05) when CaSO4 at a rate of 0.2%
was added. Though the differences from
agent to agent at high water contents
were not significant at the 0.05 level,
CaSO4 appeared to increase aggregate
stability more than CaCO3 . Surprisingly,
stability tended to be greater at
the lower rather than higher application
rates. In conclusion, aggregate stability
1. decreased with increasing water
content at freezing, and
2. increased after CaSO4-amended soil
samples at high water contents were

Item Type: Book Section
NWISRL Publication Number: 0813
Subjects: Soil
Mass Import - autoclassified (may be erroneous)
Depositing User: Users 6 not found.
Date Deposited: 20 Nov 2010 21:55
Last Modified: 01 Dec 2016 21:07
Item ID: 781