| The soil physical response to reduced and no-tillage systems is generally unquantified on the Canadian prairies. This study quantified the effects of three long-term tillage-residue systems on the soil environment and barley growth during the 9th and 10th year after treatment initiation on a fine-textured, well-aggregated and well-drained Typic Cryoboroll (Black Chernozemic) at Ellerslie, Alberta (subhumid, cryoboreal). The treatments were: no-tillage with surface straw; rototillage to a 10-cm depth with straw incorporated; and rototillage to a 10-cm depth after straw was removed.; The no till+straw treatment provided the highest residue cover, and had a more stable though lower surface roughness, larger average aggregate size (dry and water-stable), and higher organic-C content (0-5-cm depth) compared with the tilled treatments. Surface soil of the till+no straw treatment contained the most wind-erodible and water-slakable aggregates. The till+straw treatment generally had properties intermediate to those of the other two treatments. Soil bulk density (Db) was affected by treatments to approximately 10-cm depth and penetration resistance (PR) to 45 cm. Average Db and PR were greatest in the top 10 cm of the no-till treatment, but in the subsoil PR was generally greatest in the till+no straw treatment.; Plant available water capacity of the 0-15-cm depth was the lowest in the no-till treatment. Infiltration rate and saturated hydraulic conductivity (0-7.5-cm depth) were in the order: no till+straw {dollar}>{dollar}till+straw {dollar}>{dollar}till+no straw. The treatments affected the soil water content to a 100-cm depth, but seasonal evapotranspiration did not differ among treatments.; For the study period, seedling emergence was delayed and the yield lowest in the no till+straw treatment. Shoot growth was the best in till+straw. Total root mass and length in the 0-50 cm depth were unaffected by treatments; however, root length density and specific root length in 0-15 cm interval were the greatest in till+no straw. The till+straw treatment seemed to be the best from a crop production standpoint, although from a soil and water conservation perspective, the no till+straw treatment was best. |
