Effect of tillage on bare soil energy balance and thermal regime: An experimental study

Abstract

The effects of tillage on the energy balance and temperature of bare soil were studied using three plots that had different soil structures due to different times of seedbed preparation and soil compaction. The experiment was performed on a loamy soil (Gleyic luvisol) in northern France during the establishment of sugar beet in spring 1992. Temperature, water content, heat capacity and thermal conductivity of the ploughed layer, surface albedo and roughness, net radiation, soil heat flux, sensible heat flux and evaporation were all measured over a spring-tilled soil, an autumn-tilled soil and a compacted soil. Differences in soil heat fluxes were related to soil evaporation and thermal conductivity. Differences in soil temperatures were related to heat capacity. In spite of a considerable evaporation, the compacted soil had the highest soil heat flux because of its high thermal conductivity. Nevertheless, the spring-tilled soil was the warmest because of its low heat capacity, and sugar beet germinated more rapidly with spring soil tillage.