3ZCF-7700型多功能中耕除草机设计与试验

为了解决机械除草过程中作物苗间与秧苗附近杂草较难铲除以及伤苗严重和除净率低等问题,研制出与大功率拖拉机配套的3ZCF-7700型多功能中耕除草机。该机在玉米、大豆等作物的中耕作业过程中能完成侧深施肥、苗间松土除草、起垄、培土和深松等工序的作业。该文论述了3ZCF-7700型多功能中耕除草机的结构、工作原理及关键部件的设计,田间试验结果表明：用于玉米苗间杂草除净率为76%,行间杂草除净率95.7%,伤苗率小于4.4%,其它各项技术性能指标均符合设计要求。该机可满足旱田作物中耕管理作业的农艺要求。     

3GY-1920型宽幅水田中耕除草机的设计与试验

为了提高机械除草的作业效率、降低地头频繁调头引起的伤苗率,该文研制了3GY-1920型宽幅水田中耕除草机。该机由12 k W水田拖拉机提供动力,工作幅宽为5.7 m,一次作业可覆盖6行插秧机3个行程的作业宽度,并配备了4个双作用液压缸,控制整个机架的展开闭合与除草轮位置的横向调节。该文结合水田土壤特性和现有除草部件的特点,通过对除草轮的运动学与显式动力学仿真分析,设计并优化了螺旋刀齿式样除草轮,该除草轮通过与土壤及杂草的剪切、翻耕作用实现中耕除草作业。田间除草试验结果表明:在机具不同前进速度(0.3、0.6、0.9 m/s)和除草轮入土深度(3、6、9 cm)条件下,该机平均除草率为82%,伤苗率为4.8%;根据机具作业速度和幅宽可知该机作业效率为0.6~1.8 hm2/h;整机工作性能和作业效率满足水稻田机械中耕除草作业的技术要求。机械除草与化学除草产量对比试验结果表明:在试验区域内,机械除草产量高于化学除草,该研究可为中耕除草对水稻田产量的影响提供参考。     

驱动式碎土除草多功能马铃薯中耕机设计与试验

针对传统锄铲式中耕机在土壤黏重板结情况下碎土率和除草率低、培土效果不佳等问题,该文设计了集深松碎土、铲除杂草、侧深施肥、培土起垄等多功能于一体的驱动式马铃薯中耕机,并对机具关键部件进行设计与分析,确定了深松铲、碎土刀、培土器的结构以及工作参数,在设计分析的基础上进行田间试验,并与锄铲式中耕机进行对照试验。田间试验表明:本文所研制的驱动式中耕机碎土率为95.1%、除草率为96.3%、伤苗率为1.2%、土壤蓬松度达到21.5%、油耗为13.2 kg/hm^2,满足相关标准作业指标要求。对照试验表明:相较于传统锄铲式中耕机,驱动式马铃薯中耕机碎土率提高3.3个百分点、除草率提高3.1个百分点、伤苗率降低1.6个百分点、土壤蓬松度提高2.7个百分点、油耗降低28%,明显优于其作业效果,满足国家标准碎土率≥85%、伤苗率≤5%、除草率≥90%的要求。     

深松旋耕组合作业机的研制与试验研究

根据国内中等功率拖拉机配套农机具的研究现状，以机组匹配理论为依据，研制了与中型拖拉机配套的深松旋耕组合作业机，并进行了单独深松、单独旋耕和组合工况的试验。试验表明所研制的机具在作业时能充分发挥拖拉机的动力性，减少拖拉机的功率消耗。机具配置的深松铲和旋耕刀片排列合理，深松扰动影响宽度和旋耕宽度相匹配，作业时波动范围较小，偏牵矩对拖拉机方向的稳定性基本没有影响。机具的研制也为与大功率拖拉机配套新型农机具的开发提供了借鉴。     

2ZZ-3型深松培垄施肥联合作业机的设计与试验

深松培垄施肥是玉米等作物种植过程中重要的田间管理环节,具有打破犁底层,加深耕作层,改善耕层结构,提高土壤蓄水保墒、抗旱耐涝的能力。针对东北地区常年作业所导致的土壤耕层较浅、土壤板结严重以及深松阻力大的问题,结合了深松、培土和施肥等关键技术,设计一种与32.5 kW以上拖拉机相配套的可一次性完成深松培垄和追肥等多项作业的深松培垄联合作业机。以拖拉机前进速度、垄沟深松深度、培土器开角为因素,伤苗率和比阻作为评价指标,进行了三因素三水平正交试验。结果表明：各因素对伤苗率和比阻影响的主次顺序依次为深松深度、培土器开角、前进速度;因素水平上的最优组合为深松深度为25 cm,起垄犁开角为60°,前进速度为5 km/h,伤苗率均值为3.31%,比阻均值为1.97 N/cm2。经过田间试验作业性能好,各项作业指标达到了农艺要求。深松培垄同时作业减少了动力消耗,减少了工作阻力,为旱地合理耕层的构建配套机具提供了参考。     

垄台修复中耕施肥机的设计

针对东北垄作区保护性耕作由于缺乏相应的玉米中耕机具,出现秸秆覆盖地无法中耕的问题,设计了垄台修复中耕施肥机.该机利用旋耕碎秆装置在垄沟旋转作业,进行碎秆、除草,并将旋起的土分散在垄沟两侧,同时地轮驱动施肥,垄台修复轮进行镇压修垄、盖肥.田间试验结果表明,该机器防堵性能好,垄台修复和施肥效果均达到设计要求,符合东北垄作区秸秆覆盖地的使用要求.     

步进式水田中耕除草机的研制与试验

为解决水田的除草问题,增加现有机具的作业功能,该文在步进式插秧机底盘结构的基础上,研制了一种步进式水田中耕除草机。该机由步进式插秧机底盘提供动力,主要由机架、传动系统、仿形及耕深调节机构以及复合式除草部件指辊和刀辊等组成,可实现对杂草的拉拔和埋压。田间试验结果表明:该机配备复合式除草部件、工作速度为0.5m/s、除草深度为50mm时,行间除草率为83.7%,伤苗率为4.1%,可在草量多、杂草高的水田中进行有效除草。     

水稻精量穴直播机电驱式侧深穴施肥系统设计与试验

针对水稻直播施肥过程中存在肥料用量大、化肥利用率低等问题,根据水稻精量穴直播与侧深穴施肥的农艺要求,开发了一套水稻精量穴直播机电驱式侧深穴施肥系统。采用液压自平衡方式设计全方位仿形系统,对机具在作业环境中实时自动调节,保证播种、施肥作业质量;采用圆弧函数曲线优化设计施肥沟开沟器,在距垄台上芽种行水平距离30 mm处开出宽50 mm、沟型平整的施肥沟;采用电力驱动方式设计电动式外槽轮排肥器,根据需要对每个排肥器独立调节,与配套的电动部件相连,将肥料成穴施入施肥沟底。田间试验表明,在机具前进速度为2.48 km/h,排种器、排肥器工作转速均为29 r/min,施肥深度为50 mm的最优工作条件下,穴播种量、穴施肥量合格率分别为86.73%、87.49%,施肥与播种穴距匹配,各行播种、施肥穴距合格率均为100%,播种、施肥穴距变异系数分别为17.2%、16.5%,芽种破损率为0.31%;并对排种器、排肥器在14~36 r/min工作转速范围内进行可行性验证试验,施肥系统可与水稻精量穴直播机配套,同步完成开沟、侧深穴施肥、覆泥、起垄和精量穴直播多项作业工序,各项性能指标均满足水稻直播、施肥的农艺要求。该研究可为水稻精量穴直播机及其施肥关键部件的设计和评价提供参考。     

水稻精量穴直播机电驱式侧深穴施肥系统设计与试验（英文）

针对水稻直播施肥过程中存在肥料用量大、化肥利用率低等问题,根据水稻精量穴直播与侧深穴施肥的农艺要求,开发了一套水稻精量穴直播机电驱式侧深穴施肥系统。采用液压自平衡方式设计全方位仿形系统,对机具在作业环境中实时自动调节,保证播种、施肥作业质量;采用圆弧函数曲线优化设计施肥沟开沟器,在距垄台上芽种行水平距离30 mm处开出宽50 mm、沟型平整的施肥沟;采用电力驱动方式设计电动式外槽轮排肥器,根据需要对每个排肥器独立调节,与配套的电动部件相连,将肥料成穴施入施肥沟底。田间试验表明,在机具前进速度为2.48 km/h,排种器、排肥器工作转速均为29 r/min,施肥深度为50 mm的最优工作条件下,穴播种量、穴施肥量合格率分别为86.73%、87.49%,施肥与播种穴距匹配,各行播种、施肥穴距合格率均为100%,播种、施肥穴距变异系数分别为17.2%、16.5%,芽种破损率为0.31%;并对排种器、排肥器在14~36 r/min工作转速范围内进行可行性验证试验,施肥系统可与水稻精量穴直播机配套,同步完成开沟、侧深穴施肥、覆泥、起垄和精量穴直播多项作业工序,各项性能指标均满足水稻直播、施肥的农艺要求。该研究可为水稻精量穴直播机及其施肥关键部件的设计和评价提供参考。     

1GSZ-350型灭茬旋耕联合整地机的设计与试验

为了适应大马力拖拉机对配套农机具的需求,在分析研究中小型单一和组合作业模式整地机的基础上,设计研制出一种集灭茬、旋耕和深松于一体的宽幅联合整地机,并进行了单一和联合作业的试验。试验表明,该机具在作业时能够充分发挥大马力拖拉机的作业效率,减少拖拉机的功率消耗,节能约14.3%;机具配置的灭茬刀、深松铲和旋耕刀排列合理,保墒效果明显,碎土率和灭茬率高达95%。该机属于高效节能型机具,为研究大型农机具提供了参考。     

基于灭茬圆盘驱动旋耕刀多功能耕整机设计与试验

针对玉米作物根茬难清除、制约后续标准作业的问题,结合北方寒地保护性耕作工艺,设计了一种与大马力拖拉机配套的茬地耕整机。该机采用联合作业方式,能够一次完成起茬、破茬碎土、垄体深松、灭茬旋耕、起垄、垄体整形等多项作业。设计了自驱动式弧形齿盘破茬器和螺旋碎土装置,破茬器转速为33～37r/min,旋耕刀转速为350～390r/min,深松深度为30cm左右。田间试验表明,该机工作性能良好,灭茬旋耕效果显著。与传统耕作机具和进口联合整地机相比,破土率提高2.4%～6.9%,破茬率提高6.3%～12.9%,节省油耗26.3%～40.4%。     

鼹鼠多趾结构特征仿生旋耕刀设计与试验

为减小旋耕刀切土扭矩来降低旋耕机功耗,同时提高旋耕机耕作质量,该文分析了鼹鼠前肢手掌多趾组合结构和趾尖轮廓曲线特征,利用二次高斯方程拟合五个趾尖轮廓曲线(R2 0.95和SSE 0.05),并基于拟合曲线,设计了具有鼹鼠多趾结构特征的仿生旋耕刀。通过田间试验,分析传统型和仿生型旋耕刀在不同机组前进速度、转速和耕深条件下的整机功耗、土壤破碎率和沟底压实情况,得到仿生结构特征对整机田间耕作性能的影响。结果表明,当前进速度从1 km/h增加到5 km/h时,仿生型旋耕刀的整机功耗平均减小16.88%;当转速从254 r/min增加到267 r/min时,仿生型旋耕刀的整机功耗平均减小17.00%;当耕深从80 mm增加到160 mm时,仿生型旋耕刀的整机功耗平均减小21.80%。传统型旋耕刀耕后的沟底有压实现象,且沟脊高而宽,耕作效果不佳;而仿生型旋耕刀可以显著地降低耕后沟底被压实的风险,沟底平整,可进一步减小耕作功耗。2种类型旋耕刀在不同耕作条件下的整机土壤破碎率耕深稳定性、耕宽稳定性、耕后地表植被覆盖率、耕后地表平整度和土壤蓬松度在数值上相差不大,且均满足国标要求。研究结果对实现旋耕刀减阻降耗和改善耕作质量具有一定的启发。     

Short-term effects of different tillage in a sustainable farming system on nematode community structure

This study investigated the effects of different tillage practices on the nematode community structure. The different tillage systems were: untilled control, conventional deep plough, two-layer plough and cultivator. Sampling was carried out in a field experiment at Wörrstadt-Rommersheim (Rhineland-Palatinate, Germany) in order to study the effects of these tillage systems in a sustainable farming system. Soil samples were taken every 3?months from June 1994 to March 1995 and divided into two depths of 0–10 and 10–20?cm in order to study the vertical distribution of nematode density and community structure. Nematode density was significantly reduced after the first tillage. The second tillage had no effect on the nematode density, whereas the nematode community structure was strongly influenced on both structural (taxonomic) and functional (trophic group, life strategy) level. After tillage, the density of plant parasitic nematodes decreased and the density and dominance of bacterivorous nematodes increased. In the tilled plots, and especially in the cultivator and the two-layer plough plot, the nematode community was dominated by bacterial feeders, whereas, in the untilled control, plant feeders were more dominant. Our results showed that the nematode Maturity Index and Plant Parasite Index are suitable for indicating immediate tillage effects on the nematode community.     

水旱两用秸秆还田组合刀辊作业性能试验

为了检测水旱两用秸秆还田组合刀辊的田间作业质量和功率,采用无线遥测技术,利用动力输出轴一体化扭矩传感器,对安装组合刀辊的耕整机进行了田间作业质量和作业功耗优化参数性能测试试验,并与传统旋耕刀辊、螺旋刀辊进行田间作业质量及功耗对比试验。田间试验结果表明:组合刀辊性能检测试验中,水田和旱地植被埋覆率分别为94.3%和96.5%,耕深分别为20.8和20.3 cm,耕深稳定性分别为92.3%和90.6%,耕后地表平整度分别为0.9和1.2 cm,功率消耗分别为27.6和31.2 k W,均达到了设计目标;与其他刀辊对比试验中,组合刀辊作业质量优于螺旋刀辊和传统旋耕刀,作业功耗稍高。该研究可为实现水田和旱地高茬秸秆埋覆还田和土壤耕整提供参考。     

水旱两用秸秆还田耕整机关键部件设计与试验

为增加土壤的有机质含量,改善土壤的团粒结构,同时有效缓解秸秆焚烧难题,针对长江中下游地区麦-稻、油-稻等水旱作物交替种植的特点,设计了一种水旱两用型秸秆还田耕整刀辊。阐述了新刀辊的结构和工作原理,分析并确定了关键部件的结构参数,重点对传统旋耕刀的布置及其破茬理论进行了详细的分析。田间试验结果表明:水旱两用型秸秆还田耕整刀辊旋耕一遍即可实现水田和旱地秸秆埋覆、旋耕碎土、平整地表等多项功能,水田和旱地耕深分别为181.6~200.4和151.2~173.8 mm,耕深稳定性分别为92.4%~94.8%和92.4%~93.4%,耕后地表平整度均小于12 mm,植被埋覆率分别为96.3%~96.4%和90.6%~97%,碎土率为87.3%~89.6%和64.5%~90.2%,作业效果满足水稻播栽对耕整地的农艺要求。     

曲翼中耕培土装置作业参数优化与试验

中耕培土作业质量对防旱保墒、促进玉米植株生长有重要影响,合理的结构及作业参数可有效改善玉米的生长环境。针对传统中耕培土器碎土率较低、培土高度不佳的问题,该研究对曲翼中耕培土装置(以下简称曲翼培土装置)曲翼结构及其关键作业参数进行优化。首先对阻力监测系统进行改进并通过土槽试验对其可靠性进行验证;再基于装置关键部件与结构理论分析,以工作速度、曲翼夹角和入土深度为因素,培土高度和碎土率为指标进行Box-Behnken试验设计,利用Design-Expert 8.0.6软件对数据进行方差与响应面分析,建立试验因素与指标之间的回归模型,采用多指标优化法确定因素最优参数组合并进行试验验证。田间试验表明,曲翼培土装置的最优参数组合:工作速度为7.64 km/h、曲翼夹角为61°、入土深度为152 mm。在最优参数条件下进行验证试验,结果表明培土高度及碎土率分别为62.13 mm、86.78%,与预测值对比分析表明,回归模型可靠性良好。研究结果可为中耕培土装置优化、培土作业质量提高提供理论参考与技术支撑。     

Tillage techniques to reactivate aeolian erosion on inland drift-sand

The inland drift-sand areas in northern Europe are characterised by a rapid decline in both aeolian activity and areal size. Many former drift-sand surfaces have become immobilised by natural or man-induced processes, such as conversion into forest or other terrain for agricultural, economic or societal purposes. The sharp reduction of these areas automatically implies the disappearance in Western Europe of a unique landscape with a high natural and cultural-historic value. Therefore, it is necessary to investigate how drift-sand areas can be preserved, how the balance between the active areas and those colonised with drift-sand vegetation can be kept under control, and how introducing techniques that reactivate, or benefit, the aeolian processes can counteract irreversible immobilisation by subsequent colonisation. Four such techniques (rotary cultivator, beach sand cleaner, disk harrow and excavator) were evaluated during an 8-month experiment on drift-sand stabilised by grey hair grass and algae crusts at Kootwijkerzand, The Netherlands. The effect of the techniques was measured using five key-parameters: the raising and lowering of the surface due to aeolian activity, the horizontal sediment transport flux, the vertical sediment accumulation flux, changes in the grain size of the top layer due to aeolian processes, and changes in the organic matter content of the topsoil. The effect of each technique on soil compaction, surface roughness and the amount of plant residue left on the field is also discussed. The highest aeolian activity (horizontal and vertical flux, surface lowering) was observed on test fields treated with the beach sand cleaner and the rotary cultivator. The changes in grain size and organic matter content of the top layer were also highest in these fields. Of the four techniques tested, the beach sand cleaner and the rotary cultivator are thus the most recommendable methods to reactivate drift-sand stabilised by grey hair grass and algae crusts. The disk harrow and the excavator may also lead to a reactivation, but they are less effective and therefore less recommendable.     

An approach for draft prediction of combination tillage implements in sandy clay loam soil

A methodology to predict the draft requirements of combination tillage implements in any soil and operating conditions was developed. This methodology required the draft requirements of individual tillage implements in undisturbed soil condition and draft utilization ratio of the rear passive set of combination tillage implement, which is defined as the ratio of the drafts of the rear passive set operating in combination and individually. Laboratory experiments were conducted to measure the draft requirements of a reference tillage tool (single disk), three scale-model individual (moldboard plow, cultivator and disk gang) and two combination (moldboard plow with disk gang and cultivator with disk gang) tillage implements at different depths (5, 7.5 and 10 cm), speeds (1.2, 2.2, 3.2 and 4.2 km/h), wet bulk densities (in the range of 1.27–1.85 g/cm³) and cone index penetration resistance values (in the range of 445–1450 kPa) in soil bin filled with sandy clay loam soil. The average draft utilization ratio of the reference tillage tool obtained were analyzed by both orthogonal and multiple regression techniques to develop the regression equation considering soil properties, operating and tool parameters. The developed draft equation based on the above mentioned methodology was verified with the data obtained for the draft of scale-model and prototype combination tillage implements in the laboratory and field conditions, respectively. It was found that the developed equation predicted the draft of both combination tillage implements within an average absolute variation of 18.0 and 13.5%, respectively.     

Weed management systems based on animal-drawn cultivators for maize production in the Southern Highlands of Tanzania

Experiments on weed management techniques for maize production were carried out at the Uyole Agricultural Centre and on farmer's fields in Mbozi district, Tanzania, using the inter-row cultivator (Cossul), over-the-row cultivator (MOP) and hand-weeding. There were no significant differences in field capacities between the two cultivators, although the MOP cultivator tended to have slightly higher capacities. Field capacities tended to be higher when the maize was 45 cm high. The use of cultivators alone reduced labour inputs for weeding by 80%, and the use of cultivators combined with hand-weeding reduced labour by 40%, compared with hand-weeding alone. Hand-weeding alone, or in combination with cultivator weeding gave the best control of weeds, and similar high maize yields (5 t ha⁻¹ compared with 2 t ha⁻¹ with no weeding). The use of cultivators alone gave significantly poorer weed control and a yield of 3.3 t ha⁻¹. The use of cultivators plus within-row hand-weeding gave marginal rates of return greater than 1.0, indicating a reasonable return on the investment in labour. The results emphasize the importance of weeding for higher maize yields in the Southern Highlands of Tanzania. Higher yields can be obtained by manual weeding alone but at the cost of high labour inputs, representing high levels of family drudgery or high labour hiring costs. Those farmers who have access to ox-drawn systems are advised to arrange additional within-row manual weeding to ensure higher yields. Ox-drawn cultivators alone for weeding are only suitable for situations where labour is scarce.