Submitted to: ASA-CSSA-SSSA Proceedings
Publication Type: Abstract only
Publication Acceptance Date: 11/6/2005
Publication Date: 11/6/2005
Citation: Schwartz, R.C., Baumhardt, R.L., Evett, S.R. 2005. Tillage effects on near surface soil water dynamics [abstract]. Agronomy Abstracts, ASA-CSSA-SSSA Annual Meeting, Salt Lake City, Utah. 2005 CDROM. Interpretive Summary:
Technical Abstract: Tillage modifies the soil physical properties near the surface which in turn can influence evaporation rates and how water is redistributed within the profile during and after precipitation. The objective of this study was to evaluate the effects of sweep tillage on near surface soil water dynamics. Plots were established in a fallow field under stubble-mulch tillage management on a Pullman clay loam (Fine, mixed, superactive, thermic Torrertic Paleustolls). Half of the plots were periodically tilled to a depth of .08 m using a sweep plow. The remaining plots were not tilled throughout the duration of the study. All plots were devoid of residue. Soil water contents were monitored using time-domain reflectometry at 0.05, 0.1, 0.15, 0.2, and 0.3 m and using a neutron moisture meter to a depth of 2.3 m. Soil temperature was also monitored at depths of 0.05, 0.1, 0.15, 0.2, and 0.3 m. Changes in soil bulk density of the surface 0.1 m were also determined for extracted soil cores. During a 135 day period in March through August, tillage decreased net water storage by 11 mm (P < 0.05) as compared with no-tillage. Water contents at soil depths below 0.2 m were not influenced by tillage treatment. Increased evaporation under tillage was likely a result of enhanced vapor flow near the surface and greater absorption of radiation by a tilled surface with reduced albedo.