Effects of Mulch and Rainfall Intensity on Crust Strength of Three Illinois Soils
Owido, Seth Frederick Ochieng'
This item is only available for download by members of the University of Illinois community. Students, faculty, and staff at the U of I may log in with your NetID and password to view the item. If you are trying to access an Illinois-restricted dissertation or thesis, you can request a copy through your library's Inter-Library Loan office or purchase a copy directly from ProQuest.
Permalink
https://hdl.handle.net/2142/72611
Description
Title
Effects of Mulch and Rainfall Intensity on Crust Strength of Three Illinois Soils
Author(s)
Owido, Seth Frederick Ochieng'
Issue Date
1992
Doctoral Committee Chair(s)
Simmons, F. William
Department of Study
Agronomy
Discipline
Agronomy
Degree Granting Institution
University of Illinois at Urbana-Champaign
Degree Name
Ph.D.
Degree Level
Dissertation
Keyword(s)
Agriculture, Agronomy
Abstract
An experiment was conducted to study the effects of mulch and rainfall intensity on the crusting characteristics of the surface (0 to 15 cm) horizons of three Illinois soils: Drummer silty clay loam (fine silty, mixed, mesic Typic Haplaquoll); Cisne silt loam (fine, montmorillonitic, mesic Mollic Albaqualf); and reconstructed Blair silt loam (fine-loamy, mixed, mesic Aquic Hapludalf). Increased rainfall intensity significantly reduced rate of seedling emergence especially when the soil was bare. Mean period of ultimate emergence was significantly reduced while rate of emergence was increased by increasing mulch rates. The soils differed with respect to rate of emergence, and ultimate emergence. Under controlled moisture content, mulch rate significantly reduced crust strength of Cisne and Drummer but had no influence on strength of the Blair soil. Rainfall intensity slightly increased the strength of the Drummer soil but did not affect that of Cisne and Blair. Bulk density and gravimetric moisture content had major influence on crust strength of Cisne and Blair while in the Drummer, only bulk density had a significant influence. Multiple regression models developed to describe the effects of input variables on the modulus of rupture indicated that gravimetric moisture content accounted for 75% of the variation in crust strength of the Blair soil. Low regression coefficients obtained for Cisne and Drummer indicated that factors other than mulch rate, bulk density, orientation, and gravimetric water content may be responsible for the variation in their crust strength.
The effects of freeze-thaw and wet-dry cycles on crust strength of surface (0 to 15 cm) horizons of the three Illinois soils was also determined. Freezing at 0$\sp\circ$C and subsequent thawing resulted in a significant increase in crust strength. Blair silt loam showed significant reduction in strength at freezing temperatures of $-$5, and $-$10$\sp\circ$C, while Cisne and Drummer increased in crust strength. Freezing and thawing episodes affected crust strength by influencing the bulk density, especially for the Blair silt loam. Regression models indicated that freeze-thaw cycles, bulk density, and temperature of freezing accounted for most of the variation in crust strength. (Abstract shortened by UMI.)
Use this login method if you
don't
have an
@illinois.edu
email address.
(Oops, I do have one)
IDEALS migrated to a new platform on June 23, 2022. If you created
your account prior to this date, you will have to reset your password
using the forgot-password link below.
