短期翻耕和有机物还田对东北暗棕壤物理性质和玉米产量的影响

    Effects of short-term plowing and organic amendments on soil physical properties and maize yield in dark brown soil in Northeast China

    • 摘要: 构建适宜作物生长的耕层是解决农田土壤耕层"变浅、变薄、变硬"和透气透水性差的重要技术途径之一,对于土壤黏粒含量较高的土壤来说,更是如此。该研究以黑龙江省较为典型的农田暗棕壤为研究对象,在黑河市爱辉农业示范园区设置不同耕层构建模式试验,分析不同翻耕深度(15、35 cm)和不同有机物还田(秸秆和牛粪)对暗棕壤物理性质、玉米产量及产量构成的影响。田间试验包括:1)对照处理:常规浅翻15 cm,无有机物还田(T15);2)深翻35 cm,无有机物还田(T35);3)浅翻15 cm,秸秆浅混还田(T15+S);4)深翻35 cm,秸秆深混还田(T35+S);5) 免耕秸秆全覆盖(NT+SM1);6)免耕秸秆条覆盖(NT+SM2);7)深翻35 cm,有机肥深混还田(T35+OM);8)深翻35 cm,有机肥加秸秆深混还田(T35+S+OM),秸秆和有机肥的还田量分别为10 000和30 000 kg/hm2。2019年和2020年试验结果表明,不同耕作和有机物还田对土壤物理性质影响较大,与T15处理相比,T35+S、T35+OM和T35+S+OM处理可显著减少土壤容重,增加土壤孔隙度、饱和含水量、田间持水量和>0.25 mm水稳性团聚体比例,优化土壤三相比;T15+S处理对0~15 cm耕层的土壤容重、总孔隙度、饱和含水量、土壤三相比和>0.25 mm水稳性团聚体影响显著,而T35+S、T35+OM和T35+S+OM处理可显著改善15~35 cm亚耕层的土壤物理性质。不同耕层构建模式对玉米产量和收获指数也产生影响,且在不同降水年型间存在差异:与T15处理相比,在降水正常年(2019年),T35+S、T35+OM和T35+S+OM处理玉米产量差异均不显著(P>0.05);在丰水年(2020年),T15+S和T35+S+OM处理玉米产量和收获指数增加最显著,分别增加了27.6%~37.0%和22.75%~28.57%(P<0.05),免耕可导致玉米减产。翻耕配合有机物还田通过增加玉米穗长和行粒数,减少秃顶长,是玉米增产的主要影响因素。综合分析认为,深翻配合秸秆或有机肥还田能显著改善土壤物理结构,优化土壤三相比,增加玉米产量和收获指数,在东北北部暗棕壤地区构建适宜作物生长的耕层具有一定的指导意义和应用价值。

       

      Abstract: Abstract: Constructing a suitable plough layer is one of the important technical methods to solve the problem of "shallowing, thinning and hardening" of the plough layer in dry farmland, especially for soils with high soil clay content. In this study, a field experiment including different tillage layer construction models was set up in Aihui experiment garden, Heihe. Effects of different soil tillage depth (15 cm and 35 cm) and organic matter (maize straw and cattle manure) amendments on soil physical properties, maize yield and its yield components were investigated. Eight field treatments were established with four replicates and random block design, including shallow tillage (0-15 cm) without or with maize straw return (T15 and T15+S), deep plowing (0-35 cm) without or with straw return (T35 and T35+S), deep plowing (0-35 cm) with cattle manure (T35+OM) and cattle manure plus maize straw (T35+S+OM), no tillage with maize straw mulching (NT+SM1) or ridged-mulching (NT+SM2) on the surface. The returning rate of maize straw and cattle manure were 10 000 kg/hm2 and 30 000 kg/hm2, respectively. Results obtained from 2019 and 2020 showed that soil physical properties were largely influenced after one-year different soil plowing and organic amendments practices. Compared with T15, T35+S, T35+OM and T35+S+OM significantly decreased soil bulk density, increased total porosity, saturated water capacity, water holding capacity, content of >0.25 mm water-stable aggregates, as well as optimized the soil three phase ratio (P<0.05). T15+S obviously improved soil physical properties in 0~15 cm soil layer, while T35+S, T35+OM and T35+S+OM significantly improved soil physical properties in 15-35 cm sublayer. The maize yield, harvest index and yield components were also influenced by soil plowing and organic amendments practices, and seemed to differed with annual precipitation. Compared with T15, in the year of normal precipitation (2019), the maize yield in T35+S, T35+OM and T35+S+OM treatments was not significantly different (P>0.05). While in 2020 with surplus precipitation, the maize yield in T15+S and T35+S+OM and significantly increased by 27.6%-37.0%, harvest index increased by 22.75%-28.57% (P<0.05). Averaged crop yield in no-tilled soils decreased (P<0.05). Soil tillage and organic amendments significantly increased ear length and number of kernels per row, decreased bare top length, consequently caused increases in maize yield. In conclusion, deep plowing plus organic amendment into soil is a feasible agricultural management for improving soil physical properties, optimizing soil three phase ratio, and increasing maize yield. This technique is applicable in the construction of reasonable plough layer of dryland in dark brown soil in northern China.

       

    /

    返回文章
    返回