Sample processing impacts on single wet sieve aggregate stability analysis

Soil aggregate stability is widely considered an indicator of soil health. However, there is a lack of test procedure standardization for this soil property. Presently, air-drying and manual grinding are commonly used in preparing samples for testing, which are time-consuming and labor intensive. This study evaluated oven-drying (65 °C) aggregates and processing by either disk or flail mechanical grinders as a way to improve efficiency of conducting aggregate stability analysis as compared with air drying and manual grinding. Surface soil samples were collected from forest, grassland, no-till, and cultivated areas across 22 fields in Oklahoma with textures ranging from sandy loam to clay loam. The stable fractions of oven-dried samples were highly correlated to the results of the analysis that used air-drying. The stable fractions of mechanically ground samples were also highly correlated with manually ground samples. Oven-drying in combination with either of the grinding methods is a suitable way of improving the efficiency of soil aggregate stability analysis.