Soil Aggregation and Wind Erosion: Processes and Measurements

Abstract

The size distribution and stability of soil aggregates have a major influence on the wind erodibility of soils. From field and laboratory studies, we know that aggregate status is the result of external forces acting on the soil such as. tillage, wetting and drying, 'freezing and thawing, and freeze drying. The effect of these forces varies with soil properties, cropping management, and the severity of the processes. As a result of these forces, soil aggregates may either increase or decrease in size as well as stability. The effects of moisture and temperature can cause significant changes in the aggregates and thus, the erodibility of a soil. In order to relate the forces acting on soils to different properties and to wind erodibility, standardized methods are needed to measure the aggregate size distribution and aggregate stability. Standardizing these methods would allow comparison of the effects of various treatments and soil types on the aggregate status. This paper reviews the processes and measurement of soil aggregation as it affects wind erosion.