Portal de Periódicos da CAPES

2.6 Aggregate Stability and Size Distribution

2013; Linguagem: Inglês

10.2136/sssabookser5.4.c14

2163-2804

John R. Nimmo, K. S. Perkins,

Polymer-Based Agricultural Enhancements

Aggregate stability and size information may be used to evaluate or predict the effects of various agricultural techniques, such as tillage and organic-matter additions, and erosion by wind and water. This chapter emphasizes informally standardized, operationally defined methods. For the main descriptions, the most widely used method is selected for each of four properties: dry-aggregate size distribution, dry-aggregate stability, wet-aggregate size distribution, and wet-aggregate stability. The chapter discusses alternative methods, namely variations of the more standard methods as well as additional ones based on different principles, such as comparison of fast and slow wetting and interpretation of retention curves. The method of F. B. Pierson and D. J. Mulla, a modification of the high-energy moisture characteristic method proposed by E. C. Childs, is based on differences in the water-retention curves for fast-wetted and slow-wetted aggregates from replicate soil samples.