YS-3PT321型培土机的改进设计与试验研究

为了解决3PT320型培土机存在的问题,提升机械作业性能,更好地满足培土作业要求,对3PT320型培土机进行了改进,研制了YS-3PT321型培土机。通过性能检测和验证试验,证明该机各项性能指标达到设计要求且符合烟草农艺需求;与3PT320型相比,机身减小,重量减轻24 kg,可进行正转或反转培土作业,且通过能力显著增强,操作灵活轻便;生产效率达0.108 7 hm2/h,是手工培土的11.3～14.1倍,比3PT320型极显著提高了生产效率,且降低劳动强度和作业成本,同时增加了前置或后置水田旋耕作业功能。     

Tillage translocation and tillage erosivity by planting, hilling and harvesting operations common to potato production in Atlantic Canada

In Canada, the negative impacts of tillage erosion is a growing concern, especially in regions where highly erosive cropping and tillage systems are practiced on highly erodible, topographically complex landscapes. To date, tillage erosion studies have focused primarily on the movement of soil by primary and secondary tillage operations. However, in potato (Solanum tuberosum L.) production there is often considerable soil disturbance that occurs during “tertiary” field operations conducted during the growing season. Therefore, the objective of this project was to generate tillage translocation and erosivity values for implements common to planting, hilling and harvesting operations within intensive potato production systems in Atlantic Canada. Our results show that tertiary tillage operations result in significant soil displacement and can be equally as erosive as primary and secondary tillage operations. Both the planting, cultivating and hilling (PCH) sequence and the harvester moved soil extremely large distances (up to 23.6 and 6.0 m, respectively). In fact, the mean translocated distance of the tilled layer (T_L) and the mass of translocated soil (T_M) of the PCH sequence (0.42 m and 115.9 kg m⁻¹, respectively) and the harvester (0.55 m and 71.7 kg m⁻¹, respectively) are larger than those reported previously for primary and secondary tillage operations in New Brunswick. In addition, the net downslope movement of soil for the PCH sequence and the harvester was approximately 36 and 26 kg m⁻¹, respectively, suggesting that both tertiary tillage operations have the potential to be erosive. A direct relationship was observed between both T_L and T_M and slope gradient for the PCH sequence, but similar relationships were not found for the harvester, even though the harvester moved approximately 30 % more soil downslope than upslope. Linear regression functions were generally improved after including slope curvature in the model, but these results were not always significant. Soil movement by the PCH sequence and harvester were also largely influenced by tillage speed and tillage depth, and future research is needed under controlled conditions to determine whether it is changing topography or the variability in tillage speed and depth across the landscape in response to changing topography that is driving tillage erosion within mechanized agricultural systems. It is clear that tertiary tillage operations must be considered when developing best management practices to improve soil conservation strategies for potato production systems in Canada and worldwide.     

揭膜培土对烟株生长和烟叶品质的影响

[目的]研究山地特殊气候和生态条件下的烤烟揭膜培土方式。[方法]以重庆市丰都县境内种植的烤烟品种云烟87为试验材料,研究揭膜培土对烟株生长和烟叶品质的影响。[结果]与不揭膜培土处理对比,栽后40d揭膜培土效果较好。烤烟大田期农艺性状明显改善,其株高、茎围和有效叶片数显著提高;经济性状显著提升,上等烟比例、中等烟比例、均价和产量显著提高;且烟叶外观质量明显提高,其工业可用性进一步增强。[结论]揭膜培土有利于促进烟株生长和提高烟叶品质。