ARS | Publication request: Bulk Density and Soil Moisture Sensors

Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: July 12, 2007
Publication Date: September 2, 2008
Citation: Logsdon, S.D., Mbuya, O.S., Tsegaye, T. 2008. Bulk Density and Soil Moisture Sensors. In: Soil Science: Step-by-Step Field Methods. Madison, WI: Soil Science Society of America. p. 211-220.

Interpretive Summary: Consultants and other professional soil scientists want a step-by-step description of techniques and procedures to use equipment. They are not interested in a lot of theoretical description of how equipment works. The purpose of this chapter is to provide step-by-step guides on measuring soil density and soil water content. Knowledge of soil density is important for determining when compaction is too severe for root growth. Knowledge of soil water content is important for understanding plant water use and optimal conditions for field operations. The audience for this chapter are consultants, land use planners, and other professional soil scientists.

Technical Abstract: Soil bulk density is a good indicator of problems of root penetration, soil aeration, and water infiltration. Knowledge of soil water content is important to understand crop water use, leaching of chemicals, and soil trafficability. The purpose of this presentation is to detail step-by-step how to measure soil bulk density, and how to successfully use the new soil moisture sensors. Soil bulk density measurement is needed to convert soil properties from a mass to a volume basis, and is a useful indicator of soil compaction. As a qualitative measure of soil wetness, soil water content affects the level of soil compaction which is indicated by its bulk density. Numerous soil moisture sensors have been introduced, but often require site-specific calibration. Various methods are discussed, illustrated, and compared.