深松耕作对新疆绿洲棉田土壤特性及产量形成的影响

Effects of Subsoiling on Soil Characteristics and Yield Formation of Cotton Field in Oasis Area of Xinjiang

为探讨深松耕作对新疆绿洲棉田土壤特性及产量形成的影响,在秸秆还田和常规翻耕条件下,以不深松棉田为对照(SST0),设置深松30 cm(SST1)、40 cm(SST2)、50 cm(SST3)处理,研究不同深松深度下棉花关键生育期土壤指标变化及其产量形成特征。结果表明:深松能降低棉花生育期土壤体积质量、土壤紧实度,增加土壤含水率,同时使耕层土壤含盐量减小。与SST0相比,SST1、SST2、SST3处理0~60 cm土层平均土壤体积质量降低0.84%、3.94%、4.78%,土壤紧实度降低1.84%、9.49%、16.57%。蕾期、花铃期0~30 cm土层土壤含水率以SST2最高,较SST0增加31.00%、64.50%,而土壤含盐量变化则与之相反,以SST2最低,较SST0下降11.10%、19.10%。深松显著促进了棉花中后期干物质积累,深松深度为40 cm时,干物质最大积累速率V_(m)和生长特征值GT达到峰值,SST1、SST2、SST3产量较SST0提高0.26%、18.20%、2.45%。综上所述,深松40 cm时效果较好,对新疆棉田土壤特性改善和产量提高有积极作用。

In order to investigate the effect of subsoiling on soil characteristics and yield formation of cotton field in oasis area of Xinjiang,no subsoiling cotton field was taken as control(SST0),under subsoiling treatments of 30 cm(SST1),40 cm(SST2) and 50 cm(SST3),soil indexes and yield formation characteristics at key growth stages of cotton under different subsoiling depths were studied under the conditions of straw returning to field and conventional tillage.The results showed that subsoiling could reduce soil bulk density and soil hardness,increase soil water content,and decrease soil salt salinity in plough layer.Compared with SST0,under treatments of SST1,SST2,SST3,the average soil bulk density at 0-60 cm soil layer decreased by 0.84%,3.94%,4.78%,respectively,and the soil hardness decreased by 1.84%,9.49%,16.57%,respectively.At the 0-30 cm soil layer of bud stage and flowering and boll stage,SST2 had the highest soil moisture content,increasing by 31.00% and 64.50% compared with SST0,while the change of soil salt salinity was opposite.SST2 was the lowest,decreasing by 11.10% and 19.10% compared with SST0.When the subsoiling depth was 40 cm,the maximum dry matter accumulation rate V_(m) and growth characteristic value GT reached the peak,and the yield of SST1,SST2,SST3 increased by 0.26%,18.20%,2.45%,respectively,compared with SST0.In conclusion,40 cm of subsoiling is better,has positive effect on improvement of soil properties and yield of cotton in Xinjiang.