Aggregate stability response to freeze-thaw cycles

Lehrsch, G.A. (1997) Aggregate stability response to freeze-thaw cycles. pp. 165-171. In: Iskandar, I.K. and Wright, E.A. and Radke, J.K. and Sharratt, B.S. and Groenevelt, P.H. and Hinzman, L.D. (eds.) Proceedings Intl. Symposium on Physics, Chemistry, and Ecology of Seasonally Frozen Soils. USA-AK-Fairbanks, 1997/06/10-12.

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Abstract

Research has suggested that 1 to 3 freeze-thaw
cycles (FTCs) may increase the stability of soil
aggregates, when field-moist aggregates are wet sieved.
The objectives of this laboratory experiment were to
quantify aggregate stability of relatively wet aggregates
from the Ap horizons of four soils when subjected to
either 0, 1, 2, or 4 FTCs and, secondly, to identify a
threshold number of FTCs for each soil below which
aggregate stability increases. Moist soil was packed
into 28-mm-diam., 50-mm-tall brass cylinders by
tapping to a dry bulk density of 1.15 Mg m-3, sealed in
polyethylene bags, then slowly frozen convectively at
—5°C for 48 h, then thawed at +6°C for 48 h for each
Fit. The first 1 to 2 FTCs in general increased
aggregate stability, but additional Fits had little effect.
For 3 of 4 soils, 2 to 3 FTCs appeared to increase
aggregate stability to a plateau or threshold. Fits
increased aggregate stability, when averaged across the
four soils, more in the 0- to 15-mm depth increment
than in the 15- to 30-mm increment.

Item Type:	Conference or Workshop Item (Paper)
NWISRL Publication Number:	0941
Additional Information:	**A.K.A NWISRL PUBLICATION 941a**
Subjects:	Soil Mass Import - autoclassified (may be erroneous)
Depositing User:	Users 6 not found.
Date Deposited:	20 Nov 2010 21:56
Last Modified:	21 Nov 2016 20:40
Item ID:	914
URI:	https://eprints.nwisrl.ars.usda.gov/id/eprint/914