Browse on keywords: soil quality soil compaction
Search results on 12/09/13
404. Anon.. 1989. Algae: companion crop for reduced compaction.. Journal of Sustainable Agriculture (CA) 2:16..
Soil Technologies Corp. of Fairfield, IA is marketing strains of green algae to reduce compaction and improve soil aggregation. The algae produce polysaccharides which help bind soil particles together. The product Microp is applied in the spring or fall, and must be undisturbed by tillage for 3-4 weeks. Polysaccharides will leach down into the soil. Their field results show a 15% reduction in compaction at 8" depth after the first year. The cost is $6/ac.
1900. Eriksson, J., I. Hakansson and B. Danfors. 1974. The effects of soil compaction on soil structure and crop yield.. Swedish Institute of Agricultural Engineers Bull. #354.
A definitive work on soil compaction. As agricultural machinery becomes larger and heavier, the incidence of soil compaction increases. This bulletin treats both topsoil and subsoil compaction, and practical consequences. T: The relationship between clay content and water holding capacities. Root frequency for small grains in terms of root length per cm3 of soil. Comparison of total pore volume in a protected soil profile below a grassed surface, with a soil profile exposed to heavy traffic over 30 yrs. Reaction of roots to high soil resistance. Many others.
3080. Tangren, G.V.. 1979. Subsoil bulk densities in some Whitman county small grain fields.. M.S. Thesis, Dept. of Agronomy and Soils, WSU, Pullman, WA.
5245. Pikul, J.L. and R.R. Allmaras. 1986. Physical and chemical properties of a haploxeroll after fifty years of residue management.. Soil Sci. Soc. Am. J., 50(1):214-219.
Greater inference about the value of long-term crop residue management requires that soil chemical properties be measured together with soil physical properties. After 54 yrs of several different crop residue management treatments in a winter wheat-fallow system in the PNW, soil bulk density, saturated hydraulic conductivity, soil water desorption curves, soil organic carbon, and soil pH were all used to quantify the soil physical and chemical state. Quality of certain soil physical and chemical properties were altered. Changes in soil compaction since 1931 appear to be limited to the top 30m. However, soil compaction was greatest in the control and fall burn treatments where organic carbon addition was lowest. Crop residue management and fertilization with NH4 base fertilizer has had a marked effect on soil pH in the Ap horizon.
8549. Karlen, D.L., D.C. Erbach, T.C. Kaspar, T.S. Colvin, E.C. Berry, and D.R. Timmons. 1990. Soil tilth: a review of past perceptions and future needs.. Soil Sci. Soc. Amer. J. 54:153-161.
This review article explores the complex concept termed soil tilth. The term has been long used to denote the quality of a soil for cropping, particularly its physical condition. Structure and organic matter are dramatically affected by crop rotation and tillage. Prairie soils with granular structure and forest soils with crumb structure are considered to have good tilth, a combination of structure, aggregation, organic matter, and porosity. Studies in the 1950's concluded that maintenance of organic matter and a supply of residues for active decomposition were desirable and economical practices. Canadian researchers report that liming improved soil tilth. Studies of no-till have attributed yield increases to improved soil physical conditions which cannot be mimicked by fertilizer N. Many of the soil tilth questions remain unanswered. How is it quantitatively defined? Plant growth can be an indicator of soil tilthfor many studies since it integrates various soil factors.