草地切根施肥补播开沟装置的设计与试验

为克服草地土壤坚实度高、残茬根系量大带来的开沟问题,在草地切根改良的基础上实现施肥补播,采用破土刀齿破茬-种沟双圆盘开沟器开沟覆土-肥沟双圆盘开沟器压土成沟并覆盖种沟的工艺构建种床与肥床,设计分层交错式覆土开沟装置,建立种沟与肥沟双圆盘开沟器需满足的参数关系。基于土壤扰动造成土壤坚实度下降理论,通过对比试验,确定种沟开沟器距切根沟缝的距离对土壤坚实度的影响,得到将种沟开沟器布置在距离切根沟20mm处,可使开沟器入土处的土壤坚实度下降62%。将分层交错式覆土开沟装置应用于9QFB-2.4型破土切根施肥补播复式作业机,田间试验结果表明:该装置能够实现稳定开沟,形成深47.3mm、宽29.1mm的肥床与深44.7mm、宽19.5mm的种床,施肥和播种深度合格率分别达到80%和83%,且对土壤的扰动程度小于14%,有利于草场植被的保护。

Design and experiment of furrowing device for root cutter with fertilization and reseeding in grassland

The layered taggered covering furrowing device was designed to solve the difficulty in furrowing for grassland where the soil firmness is very high and the amount of the stubble and root are too great,and to realize fertilization and reseeding based on root cutting.The device included the process of stubble cutting with cutting blade,forming seed bed and covering it with seeding double disc furrow opener,forming fertilizer bed and covering it with fertilization double disc furrow opener pressing down the soil to the specify depth in the root cutting opening and pushing the soil to cover the seed.Results of comparison experiment showed that the relationship between the soil firmness and the distance between the seed bed and the rootcutting opening could be used to determine the arrangement of the two double disc furrow openers.It was confirmed that compared with the control group the average firmness of the soil decreased 62% when the above distance was 20 mm.The function that the parameters of the two furrow openers should be satisfied through theoretical deduction was established.The furrowing device was used on the 9QFB2.4 root cutter with fertilization and reseeding compound machine in the field experiment.The result showed that the device can furrow stably and form suitable fertilizer bed and seed bed.The depth and width of the fertilizer bed was 47.3 mm and 29.1 mm.The depth and width of the seed bed was 44.7 mm and 19.5 mm.The stability of fertilizing and seeding depth could achieve 83% and 80%,respectively.While the soil broken rate was just 14%,which benefits for the protection of the grassland vegetation.