Bulk Density Determination by Automated Three-Dimensional Laser Scanning

This study examined the application of a relatively new automated three-dimensional scanning technology to bulk density determination of intact soil clods and rock fragments. The method uses an inexpensive commercially available three-dimensional desktop scanner. Measurements obtained by the scanning method were compared with those of the paraffin-coated clod method determined on the same clods. Results showed excellent agreement between volume and bulk density measurements obtained by the two methods across a wide range of textural classes. Use of the technology has several important advantages over the traditional clod method. The nondestructive nature of the scanning method makes it possible to use the same intact ped or clod for other purposes, such as thin sections for micromorphological analysis. In addition, high-resolution digital imaging opens up possibilities for new physical measurements of soil morphological features.