Freezing Effects on Aggregate Stability Affected by Texture, Mineralogy, and Organic Matter

Abstract

Aggregate stability, an important property influencing a soil's response to erosive forces, is affected by freezing. The objectives of this laboratory study were to determine how constrainment, number of freeze-thaw cycles, and water content at freezing affect the aggregate stability of six continental USA soils differing in texture, mineralogy, and organic-matter content. Moist aggregates, after being frozen and thawed either zero, one, three, or five times, were vapor wetted to 0.30 kg kg-' and analyzed by wet sieving. Soils with clay contents of 17% or more and organic-matter contents >3% were the most stable after freezing. Aggregate stability for fine-and medium-textured soils generally decreased linearly with increasing water content at freezing. This linear decrease in stability was more rapid for constrained samples than for unconstrained samples. The stability of field-moist aggregates generally increased from zero to one or three freeze-thaw cycles. For at least one low-organic-matter soil, stability increased from one to three freeze-thaw cycles, but then decreased at five cycles. After thawing, aggregates at water contents of 0.15 kg kg ' or more that were constrained when frozen were always significantly less stable than aggregates that were unconstrained when frozen.

Controlling Sprinkler Irrigation Runoff, Erosion, and Phosphorus Loss With Straw and Polyacrylamide

“…Four or five days following the third irrigation, except for the first replication of Test 1, we took 5-mmdeep surface soil samples from four locations in each box for wet aggregate stability determinations. The soil samples were lifted from the soil surface with spatulas, sealed in plastic bags, and refrigerated prior to analysis according to the procedure described by Kemper and Rosenau (1986) as modified by Lehrsch et al (1991). After collecting aggregate stability samples, we removed about 40 mm of surface soil from all boxes to ensure that no residual PAM remained (Malik et al, 1991).…”

Polymer and sprinkler droplet energy effects on sugar beet emergence, soil penetration resistance, and aggregate stability

“…Sugar beet was planted into a moist seedbed in early spring per standard grower practice. The soil studied in the laboratory and at Field Sites 1 and 3 was a structurally unstable Portneuf silt loam, a coarse silty, mixed, superactive, mesic Durinodic Xeric Haplocalcid (Lehrsch et al, 1991). The Portneuf's Ap horizon contained about 560 g silt kg-I and 220 g clay kg-I (USDA classification).…”

“…The aggregate stability of these samples was measured using the procedure of Nimmo and Perkins (2002), modified by Lehrsch et al (1991). The principal modification was that field-moist Ito 4-mm aggregates, rather than air-dry 1-to 2-mm aggregates, were aerosol-wetted using a non-heating vaporizer (Humidifier Model No 240, Hankscraft', Reedsburg, WI) prior to wet sieving.…”

The remediation method of sandy land in the feldspathic sandstone area

“…It was reported that the soil texture and its aggregates stability was affected by freezing and thawing process (Lehrsch et al 1991;Mbagwu and Bazzoffi 1989). Alternation of the soil freezing and thawing could effectively break the soil macro-aggregates into micro-aggregates and could increase the stability of soil aggregates on soil surface (Oztas and Fayetorbay 2003).…”