翻耕与改良剂施用对土壤植烟适应性的影响

Effects of Tillage and Amendment Application on the Suitability of Soils for Tobacco Cultivation in Tobacco-Planting Areas

在重庆市典型烟区进行了2a时间的田间试验，研究了土壤翻耕深度、土壤改良剂类型及其施用方式等土地整理因子对植烟土壤质量的影响，评估了整理后土壤的植烟适宜性．结果表明，土壤翻耕可改善土壤物理性质，使得土壤容质量下降1.38％～15.17％，孔隙度增加1.68％～18.68％，但同时也降低了土壤的有机质、有效氮、磷、铁、锰、铜等含量，且随土地整理深度增加，降低幅度增大．石灰、生物质炭、堆肥等土壤改良剂在改善土壤主要理化性质因子中的作用方向和程度不同：石灰提升土壤pH值但降低养分有效性，生物质炭促进有机质积累且强化石灰效应，而堆肥既可改良土壤物理性质，还能平衡土壤养分供应．3种改良剂之间的复配施用更能协同改善土壤理化性质及其植烟适宜性．改良剂在土壤的表层施用效果优于全层混合施用．

Effects of soil turnover depth and application of amendments on the physico‐chemical properties of tobacco‐planting soils were studied through a two‐year field experiment , conducted in Pengshui , Chongqing from April ,2012 to September ,2013 ,and the suitability of soils for tobacco cultivation after consolidation was evaluated .The results indicated that turnover of soil ameliorated its physical properties ：soil bulk density was reduced by 1.38% -15.17% and soil porosity increased by 1.68% -18.68% ;how‐ever ,it decreased the contents of soil organic matter and reduced the availabilities of nitrogen ,phosphor‐us ,iron ,manganese and copper .These negative effects increased with the increase in soil plough depth . Lime ,biochar and compost showed different roles in ameliorating soil physico‐chemical properties ：liming increased soil pH but reduced the availabilities of most nutrients ,biochar promoted the accumulation of soil organic matter and enhanced the role of lime in acid soil improvement ,while compost had positive roles both in improvement of soil physical properties and balanced supply of nutrients .Combined applica‐tion of the soil amendments tested showed a synergistic effect for improving soil physico‐chemical proper‐ties ,resulting in better suitability for tobacco cultivation .Topsoil application of amendments showed bet‐ter effects than application to the w hole soil profile .