烟草垄体分层施肥土壤镇压试验与肥料颗粒偏移分析

Tobacco ridge layered fertilization soil compaction test and analysis of fertilizer particle migration

【目的】研究烟草起垄分层施肥镇压复合作业时,镇压压强P与土壤下陷量B的关系、土壤下陷量B与据表层150 mm处的土壤坚实度M的关系及土壤内部肥料颗粒的偏移情况,为镇压装置与分层施肥装置关键结构的设计提供理论基础。【方法】通过改变施加载荷的大小进行镇压试验,测量垄体表层土壤下陷量B和距离表层150 mm处的土壤坚实度M,获得P-B曲线和B-M曲线,根据烟草移栽农艺要求确定土壤下陷量B和压强P的范围。通过EDEM仿真,得到土壤镇压作业时内部颗粒的偏移情况。【结果】得到了在符合作物生长需求的条件下,镇压产生的土壤下陷量B的范围为5~33 mm,相应施加在土壤表面的压强P为5~23 kPa;在土壤下陷量B为25 mm时,分层施肥肥料颗粒向下偏移量分别为20.2、15.1、7.7、4.8 mm,与镇压试验结果误差为10.0%~14.6%。最后通过田间试验进行验证。【结论】根据土壤压缩及内部颗粒偏移规律设计分层施肥镇压装置,垄内分层施肥深度稳定,整形效果良好,可为镇压装置及垄内分层施肥装置的设计提供参考。

【Objective】The aim of the study is to investigate the relationship between the compaction pressure P and the soil settlement amount B during the compound operation of ridging and fertilization in tobacco cultivation,as well as the relationship between the soil settlement amount B and the soil firmness M at a depth of 150 mm below the surface,and the displacement of fertilizer particles within the soil.This research aims to provide a theoretical basis for the design of key structures of compaction and layering fertilization devices.【Method】compaction tests were conducted by varying the applied load to measure the settlement amount B of the surface soil of the ridge and the soil firmness M at a depth of 150 mm below the surface.This allowed for the derivation of the P-B curve and the B-M curve.The range of settlement amount B and pressure P was determined based on the agricultural requirements for transplanting tobacco.Additionally,EDEM simulations were employed to obtain information on the displacement of internal soil particles during compression.【Result】The obtained range of soil amount B generated by compaction under conditions suitable for crop growth was found to be 5 to 33 mm,with pressure P applied to the soil surface ranging from 5 to 23 kPa.At a soil amount of 25 mm,the downward of particles in layering fertilization was measured at 20.2 mm,15.1 mm,7.7 mm,and 4.8 mm,with an error of 10.0%to 14.6%compared to the results of the test.Finally,field experiments were carried out to verify the results.【Conclusion】A mathematical model relating compaction pressure to soil settlement,soil settlement to soil firmness,and the displacement of multiple layers of fertilizer particles within the soil during compression has been established.These findings can serve as valuable references for the design of compaction and layering fertilization devices.