Evaluating the Effects of Tillage Practices on Soil Bulk Density by Least Limiting Water Range

Effects of tillage practice on soil bulk density were compared using the least limiting water range (LLWR). The results showed that compared with mouldboard plow (MP), no tillage (NT) increased the soil bulk density in the 5 cm~20 cm soil layers. The upper and lower limits of LLWR were determined by field capacity and soil resistance, respectively. The values of LLWR under NT and MP ranged from 0.155 cm³·cm^-3 to 0.174 cm³·cm^-3, which were lower under NT than MP treatments. There was a significant negative correlation between LLWR and soil bulk density. LLWR can evaluate the effect of no tillage on soil bulk density.