立式旋耕对小麦生长季土壤紧实度及产量的影响

为了探究土壤立式旋耕方式对小麦生长季关键生育时期土壤紧实状况的影响，以常规旋耕（TR，12 cm±5 cm）为对照，连续两季（2017—2018年和2018—2019年）研究了立式旋耕（VR，30 cm±5 cm）在不施肥（nF）、施肥（F）条件下小麦关键生育时期土壤紧实度、产量及养分效率的变化。结果表明，与常规旋耕相比，立式旋耕能连续两季持续增加小麦产量，提高氮肥利用率，降低耕层土壤紧实程度；而且立式旋耕能进一步激发土地生产潜力，与常规旋耕不施肥（nFTR）处理相比，2018年立式旋耕施肥（FVR）、常规旋耕施肥（FTR）处理产量分别增加50.16%、36.28%，2019年分别增加42.91%、34.79%。与FTR处理相比，FVR氮肥农学效率提高38.29%（2018年）、23.35%（2019年）；氮肥偏生产力提高10.15%（2018年）、6.02%（2019年）。与常规旋耕相比，立式旋耕能显著降低第一季小麦拔节期、灌浆期10 cm土壤耕层的紧实度；而第二季处理间差异不显著。立式旋耕能降低小麦拔节期20 cm耕层土壤紧实度，在施肥情况下显著降低。两种耕作方式下灌浆期5 cm耕层的土壤紧实度差异不显著。研究表明，立式旋耕较常规旋耕能够有效降低当季小麦拔节期、灌浆期耕层（10 cm）土壤的紧实度，构建良好的土壤结构，提高小麦产量和养分利用率。

Effects of vertical rotary tillage on wheat yield and soil compaction during wheat growing seasons

To explore the effects of vertical rotary tillage(VR)on soil compaction during the wheat growth periods, the effects of VR(30 cm±5 cm)and traditional rotary tillage(TR,12 cm±5 cm)under no fertilization(nF)and fertilization(F)levels, respectively, on wheat grain yields, nitrogen use efficiency, and soil compactions during two consecutive seasons(2017-2018 and 2018-2019)were studied. The results showed that VR increased wheat yield, improved nitrogen use efficiency, decreased soil compaction, and improved soil productivity compared to TR. Compared with nFTR treatment, FVR and FTR treatment related grain yield increased by 50.16% and 36.28%, respectively, in 2018 and by 42.91% and 34.79%, respectively, in 2019. Nitrogen agronomic efficiency of FVR increased by 38.29% in 2018 and 23.35% in 2019 compared with FTR. Partial factor productivity of nitrogen for FVR treatment increased by 10.15% in 2018 and 6.02% in 2019. Compared to TR, VR significantly reduced soil compaction in the 10 cm soil layer depth at the elongation stage and filling stage in the first season. However, there were no significant differences between the two tillages in the following season. VR tillage could also reduce soil compactions in the 20 cm soil layer depth at the elongation stage, and significantly reduced soil compaction under fertilizer conditions. Additionally, there were no significant differences between the two tillage for soil compactions in the 5 cm soil depth layers. VR could effectively decrease soil compaction in the 10 cm soil layer depth at the wheat elongation and filling stages, constructed better soil structures, and increased wheat grain yields and nitrogen agronomic efficiency.