Submitted to: American Society of Agronomy Meetings
Publication Type: Abstract Only
Publication Acceptance Date: September 1, 2003
Publication Date: November 2, 2003
Citation: Guber, A.K., Levkovsky, E., Pachepsky, Y.A. 2003.[Abstract]. Mass-size scaling in soil aggregates as affected by aggregate moisture contents and soil compaction. American Society of Agronomy Meetings. November 2-6, 2003, Denver, CO. p. 101.
Aggregate size distributions are commonly used to characterize soil structure. Information about soil structure can also be derived from examining dependencies of aggregate masses or densities on aggregate size. Density-size relationships in air-dry aggregates were reported to follow predictions of a model assuming aggregates to be mass fractals. It was recently demonstrated that such model is applicable to wet aggregates if parameters of this model are assumed to be linear functions of gravimetric water contents. The objective of this work was to evaluate sensitivity of fractal parameters to soil compaction caused by wheel traffic. Irrigated ad non-irrigated plots were laid out at silty clay Argiudoll under fallow, and treatments of one tractor pass and three tractor passes were applied. Volume of individual aggregates for four depths in the plow layer was measured with the kerosene method at air-dry water content, at saturation and at two intermediate water contents. The mass fractal model fitted data in a satisfactory manner. Both the slope and the intercept of the dependence of the fractal dimension and the reference aggregate mass on water contents were more sensitive to compaction than soil bulk density and aggregate size distributions. Parameters of fractal scaling showed a promise to diagnose compaction in studied soil.