Technical Note: Bulk Density, Water Content, and Hydraulic Properties of a Sandy Loam Soil Following Conventional or Strip Tillage

Abstract

Tillage produces a more favorable soil physical environment for seed germination and plant growth. A 2-year study was carried out to compare effects of conventional (CT) and strip (ST) tillage practices on soil bulk density, water content, final infiltration rate (Ir) and saturated hydraulic conductivity (Ks) for a Lihen sandy loam where sugarbeet (Beta vulgaris L.) was grown during the 2007 and 2008 growing seasons. Under each tillage system, we measured soil bulk density and water content using soil cores collected from the center of crop rows in all plots at soil surface (0 to 10 cm) and 10-to 30-cm depths. At both depths under each tillage system, we measured in-situ Ir using a pressure ring infiltrometer (PI) and in-situ Ks using a constant head well permeameter (CHWP). Although we noted a significant difference in soil bulk density between CT and ST plots at 10- to 30-cm depth in 2007, soil water content did not differ significantly between CT and ST plots in 2007. In 2008, soil bulk density and water content did not differ significantly between CT and ST plots at both depths. The log-transformed Ir was affected by tillage practice at P <= 0.1 in 2007 but was not significantly affected in 2008. The effects of tillage on log-transformed Ks were significant at P <= 0.05 in 2007 and P <= 0.1 in 2008. Soil Ks values were 68% and 56% greater for ST than for CT in 2007 and 2008, respectively. We concluded that ST reduced soil compaction in the row, consequently increased total porosity, reduced soil bulk density, and thereby increased Ir and Ks in the soil.