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玉米钵苗移栽可以延长作物生育期,大幅度提高粮食单产和品质。为了解决国际移栽装备结构复杂、成本高、效率低,仅适用于经济作物的问题,该文提出了一种结构简单、成本低、效率高的全自动玉米钵苗移栽机核心工作部件——顶出式有序分秧机构。采用连续输送的纵向送秧方式,设计了并排均布按顺序逐次顶出的分秧形式,分别完成同一排秧苗连续有序的快速顶出。提出了机构相关部件的结构设计参数及设计依据,同时利用渐开线反转法设计了关键部件杠杆的轮廓曲线。完成了该机构的虚拟样机运动学与动力学仿真分析与验证。利用顶出式有序分秧机构进行了玉米钵苗的顶出翻转试验,得出当土钵质量为10 g、秧苗高度为160 mm时钵苗转体高度符合机构设计与栽植要求。利用自制的顶出式有序分秧机构试验台,结合高速摄像技术完成了机构顶出均匀性台架性能试验,验证了该机构性能的合理性;对所研制的试验物理样机进行了田间试验,获得了90.4%的移栽成功率,满足旱地栽植标准,也为开发相关作物的顶出式钵苗移栽机奠定了研究基础。 相似文献
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水稻钵苗空气整根气吸式有序移栽机的研究 总被引：7，自引：3，他引：7
采用空气整根育秧技术对水稻钵苗进行育秧试验，提出了水稻钵苗空气整根育秧、气吸取苗和投苗的有序移栽方案。试验结果表明，采用空气整根培育钵苗，根系遍布整个钵腔，生物学特性优于常规钵育秧，且移栽时钵体不易破碎和倒伏。采用空气整根钵盘，以较小的吸力，钵苗就可从钵腔底部取出，实现不伤苗和根的钵苗有序移栽。对气吸式水稻钵苗有序移栽机的总体方案设计、横纵向移箱装置、投苗装置进行了分析和研究，研制了样机。试验结果表明，由步进电机驱动齿轮齿条机构控制横纵向送秧箱，驱动曲柄摆杆机构控制吸气活门，由电磁铁控制导苗管投苗活门的单 相似文献
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华南双季稻区水稻不同机械化栽植方式对比试验与评价 总被引：2，自引：6，他引：2
为探索不同机械化栽植方式对华南双季稻区的适应性及其影响机理,2011-2014年连续4 a在广东省肇庆市和江门市,以钵体苗人工手插为对照,安排了钵体毯状苗机插、毯状苗机插和毯状苗窄行机插3种机械化栽植方式的对比试验。应用主效可加互作可乘(additive main effects and multiplicative interaction,AMMI)模型对影响水稻产量的栽植方式、环境和二者的互作进行了分析,进而对不同栽植方式的适应性进行了评价。结果表明:不同栽植方式水稻产量的单因素方差分析显示,3种机械化栽植方式对常规稻都具有良好的适应性,可替代人工手插大面积推广使用;而杂交稻各次试验中3种机插秧栽植方式的产量都低于人工手插,杂交稻机插秧问题还需进一步研究。AMMI分析中,栽植方式平方和、环境平方和及二者的互作平方和分别占处理平方和的6.39%、85.29%和8.31%,都达到了极显著差异水平(P0.01);AMMI模型的交互效应主成分(interaction principal component analysis,IPCA)前2个达到显著水平,两项累计解释了互作平方和的92.99%;残差均方根(root mean square,RMS)的值为49.34 kg/hm2,占总均值的0.71%,表明AMMI2模型对试验的数据结构进行了很好的拟合。适应性评价显示,人工手插的平均产量最高,与环境存在较大正互作,是目前杂交稻种植中最好的栽植方式,但稳定性欠佳;毯状苗机插的平均产量最低,与环境的互作最小,是一种稳定性较好的栽植方式;钵体毯状苗机插的稳定性不及毯状苗机插,但平均产量高于毯状苗机插,与毯状苗机插相比平均增产约-2%~6%;毯状苗窄行机插的稳定性不及钵体毯状苗机插,但平均产量与钵体毯状苗机插相差不大,在杂交晚稻种植中常常高于钵体毯状苗机插。研究结论对推进华南双季稻区种植机械化的发展具有重要参考价值。 相似文献
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油菜移栽机分苗装置分苗过程与钵苗钵体完整性分析 总被引：1，自引：3，他引：1
针对部分分苗装置适应性差、钵体易破损及结构复杂的问题,提出一种输送带式钵苗分苗装置,构建了分苗过程中送苗与分苗阶段的运动学模型,开展了不同挤压方式下的钵体完整性试验,分析得出了输送平稳、钵体完整的条件。结果表明:钵苗在特定基质成份及含水率前提下钵体上边缘最小屈服力为6.8 N,钵体上边缘及侧面受重复挤压力时均有较好的恢复性。钵苗送苗阶段输送平稳性与摩擦系数关系较大,完整性与钵苗自身的屈服力和挤压力有关;钵体在分苗阶段满足完整性前提下,夹持力越大,夹持高度越低,钵苗稳定性越好。分苗合页的动摩擦系数μ1≤0.3375,输送带的动摩擦系数μ2满足0.5μ1μ2≤0.3375,钵苗抗挤压破损力大于1.99 N时,油菜钵苗在送苗阶段可平稳输送且保持完整。该研究为油菜钵苗移栽机结构改进提供了参考。 相似文献
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半自动压缩基质型西瓜钵苗移栽机设计与试验 总被引：8，自引：7，他引：1
针对目前使用压缩基质培育的钵苗无法使用现有移栽机械完成栽植工作的问题,模仿人工先打穴后放苗的移栽方式,设计了一种半自动压缩基质型钵苗移栽机,包含有间歇式打穴装置、持苗栽植装置和钵苗输送装置。通过单因素试验测得2组不同含水率的西瓜钵苗的钵体侧面与滑道的摩擦系数分别为0.755、0.634,并分析了2组钵体抗压载荷与压缩量之间的关系。根据西瓜种植农艺要求及西瓜钵苗外形尺寸,确定了打穴器及钵苗夹持机构的结构尺寸。按照已知运动规律对摆动机构进行优化设计,阐述了持苗栽植装置的工作过程,使用解析法对其进行了运动分析。试验结果表明,拖拉机保持2.1~2.6 km/h的速度前进时,该机作业的平均株距为98.6 cm,株距合格率为90.62%;倒伏率为21.9%,能够基本满足西瓜钵苗移栽的要求。该研究为半自动压缩基质型西瓜钵苗移栽机的设计提供了参考。 相似文献
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夹茎式番茄钵苗取苗机构设计与试验 总被引：1，自引：1，他引：0
为避免取苗机构在夹取钵苗过程中对钵体与根系造成损伤,该研究针对夹茎取苗方式,提出一种基于二阶椭圆齿轮行星轮系以及凸轮摆杆机构的夹茎式番茄钵苗取苗机构。依据二阶椭圆齿轮传动特性与机构工作原理,建立机构运动学理论模型,并对凸轮轮廓曲线进行设计,结合番茄钵苗取苗作业要求及机构特点,基于MATLAB软件开发机构分析软件对机构参数进行优化,并进一步分析优化后取苗轨迹与凸轮各工作段的对应位置关系,建立了夹茎式取苗机构虚拟样机模型,利用ADAMS软件对取苗机构运动过程进行仿真分析,验证机构参数优化结果及零部件结构设计的准确性与合理性。试制取苗机构物理样机开展高速摄影试验,通过对比分析实际工作轨迹与理论分析及仿真轨迹的一致性,验证了取苗机构设计的正确性。搭建自动取苗试验台进行取苗试验。试验结果表明,取苗机构工作性能可靠、稳定,取苗频率为80株/min时,取苗成功率为92%,投苗成功率为94.2%,伤苗率为2.9%。研究结果可为番茄钵苗全自动移栽机自动取苗机构的研发提供参考。 相似文献
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【目的】以富士（Fuji）、 秦冠（Qinguan）嫁接在平邑甜茶（Malus hupehensis Rehd.）上的当年生盆栽苗为试验材料,采用砂培方法,研究了缺氮胁迫和干旱对富士和秦冠生长情况、 光合参数、 植株各部位氮磷钾含量及氮素利用效率的影响,分析比较了低氮干旱条件下富士和秦冠生长及氮素利用的差异,以期为果树生产高效肥水利用提供理论指导。【方法】试验共设四个处理: 正常氮正常水（ZZ）、 低氮正常水（DZ）、 正常氮干旱（ZG）、 低氮干旱（DG）。氮素和水分均设置两个水平,分别为正常氮（6 mmol/L NO-3-N）、 低氮（0.3 mmol/LNO-3-N）、 正常供水（保持盆中砂子相对含水量为饱和含水量的80%~85%）、 干旱处理（保持盆中砂子相对含水量为饱和含水量的60%~65%）。【结果】富士和秦冠的生物量（茎和叶）、 株高茎粗等生长指标以及光合速率、 气孔导度、 蒸腾速率均为正常氮正常水（ZZ）＞低氮正常水（DZ）＞正常氮干旱（ZG）＞低氮干旱（DG）,并且相对应处理下秦冠的以上指标均高于富士;正常供水下,缺氮处理使富士、 秦冠的根冠比比正常氮处理均有所增加,富士提高了2.05%,秦冠提高了22.40%。富士和秦冠的氮、 磷、 钾含量均表现出正常氮正常水（ZZ）＞低氮正常水（DZ）＞正常氮干旱（ZG）＞低氮干旱（DG）; 氮、 钾元素含量在植株各部位的分布顺序依次是叶＞根＞茎,磷元素则是根＞叶＞茎;光合氮素利用效率（PNUE）和氮素利用效率表现为秦冠处理之间差异极显著,富士处理之间差异不显著;秦冠的PNUE和NUE明显高于富士,在低氮正常水（DZ）处理下,秦冠氮肥利用率比富士高42.07%,在低氮干旱（DG）处理下高64.14%;低氮胁迫下富士和秦冠的NUE显著提高,并且秦冠提高的幅度高于富士。【结论】施用氮肥能够显著提高富士与秦冠的干物质量,同等水肥条件下,秦冠生长优于富士;水分亏缺会减少叶片对氮的吸收,干旱条件下适度增施氮肥,可提高果树的抗旱能力;低氮干旱胁迫下秦冠的生长指标、 光合指标及氮素利用效率指标均优于富士,表现出较强的抗低氮干旱胁迫的能力。 相似文献
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Kyle Devey Michael Mucalo Gordon Rajendram Joseph Lane 《Communications in Soil Science and Plant Analysis》2015,46(4):72-80
Laser-induced breakdown spectroscopy (LIBS) is a new technique for the analysis of plant material. This study investigates the application of LIBS to pasture-based plant samples. The LIBS measurements were obtained from pelletized pasture samples (100 samples) that had been also analyzed by inductively coupled plasma–optical emission spectroscopy (ICP-OES) following microwave digestion for calibration and comparison purposes. Comparisons for elements sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), boron (B), phosphorus (P), and sulfur (S) showed that LIBS could be used for almost all the standard profile total elements with concentrations down to low mg/kg levels (observed error of Na: 0.024 percent, K: 0.18 percent, Mg: 0.016 percent, Ca: 0.073 percent, P: 0.017 percent, Mn: 31 mg/kg, Fe: 150 mg/kg, Zn: 6.6 mg/kg, and B: 1.1 mg/kg). Elemental analysis at less than mg/kg levels was not possible using LIBS. The elements S and Cu were particularly difficult to analyze with reliability using LIBS at the concentration levels found in the plant samples. Replacing microwave digestion and subsequent ICP analysis with a direct analysis of dried plant samples using LIBS has the potential to improve the productivity and reduce the cost of testing. 相似文献
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《中国生态农业学报》2014,(8)
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology, 相似文献
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Aleš Lebeda Ivana Doležalová Eva Křístková Barbora Mieslerová 《Genetic Resources and Crop Evolution》2001,48(2):153-164
Staff members of the Department of Botany of Palacký University in Olomouc and Gene Bank Department – Workplace Olomouc, Research Institute of Crop Production in Prague, Czech Republic, conducted an expedition in seven European countries (Austria, Czech Republic, France, Germany, Italy, the Netherlands, Switzerland) in August/September 1999 to collect wild Lactuca spp. germplasm and study its geographic distribution, ecology and biodiversity. During the mission, more than 600 locations were visited resulting in the collection of 602 seed samples (accessions) of wild Lactuca species and 13 seed samples of related genera (Chondrilla and Mycelis). Lactuca serriola f. serriola, L. serriola f. integrifolia, L. saligna and L. viminea subsp. chondrilliflora were prevalent in southern Europe (Italy, France), however, only L. serriola was common in central and western Europe (Austria, Czech Republic, Germany, Netherlands, Switzerland). The greatest diversity of Lactuca species was found in France, where also the most seed samples (165) were collected. The most characteristic habitats with a high density of Lactuca spp. populations were observed along roads and highways, grassy ditches, ruderal communities, and dust-heaps. Natural infections by powdery mildew (Erysiphe cichoracearum) and downy mildew (Bremia lactucae) on some wild Lactuca spp. were observed. Recent observations concerning the geographic distribution, population structure, habitats, and natural occurrence of diseases of Lactuca spp. are discussed. This assemblage of genetic resources of Lactuca spp. can serve as the basis of future studies of species diversification, spatial population structure, plant microevolution, domestication processes, and genetic variability of host-parasite interactions. 相似文献
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M.A. Callaham Jr. J.M. BlairT.C. Todd D.J. KitchenM.R. Whiles 《Soil biology & biochemistry》2003,35(8):1079-1093
The responses of tallgrass prairie plant communities and ecosystem processes to fire and grazing are well characterized. However, responses of invertebrate consumer groups, and particularly soil-dwelling organisms, to these disturbances are not well known. At Konza Prairie Biological Station, we sampled soil macroinvertebrates in 1994 and 1999 as part of a long-term experiment designed to examine the effects and interactions of annual fire, mowing, and fertilization (N and P) on prairie soil communities and processes. For nearly all taxa, in both years, responses were characterized by significant treatment interactions, but some general patterns were evident. Introduced European earthworms (Aporrectodea spp. and Octolasion spp.) were most abundant in plots where fire was excluded, and the proportion of the total earthworm community consisting of introduced earthworms was greater in unburned, unmowed, and fertilized plots. Nymphs of two Cicada genera were collected (Cicadetta spp. and Tibicen spp.). Cicadetta nymphs were more abundant in burned plots, but mowing reduced their abundance. Tibicen nymphs were collected almost exclusively from unburned plots. Treatment effects on herbivorous beetle larvae (Scarabaeidae, Elateridae, and Curculionidae) were variable, but nutrient additions (N or P) usually resulted in greater densities, whereas mowing usually resulted in lower densities. Our results suggest that departures from historical disturbance regimes (i.e. frequent fire and grazing) may render soils more susceptible to increased numbers of European earthworms, and that interactions between fire, aboveground biomass removal, and vegetation responses affect the structure and composition of invertebrate communities in tallgrass prairie soils. 相似文献
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Thomas Larsen Jesper Luxhøi Jakob Magid Lars Stoumann Jensen Paul Henning Krogh 《Biology and Fertility of Soils》2007,44(1):59-68
We have studied the effect of anaerobically digested (ADMSW) and composted municipal solid waste (CMSW) on mineralization
and foodweb dynamics to verify the hypothesis that ADMSW would immobilize N right after addition to soil in contrast to addition
with CMSW. Another hypothesis was that the mesofauna (enchytraeids and microarthropods) would stimulate N release from the
decomposer community. We measured excretion of -N and urea-N from the mesofauna and hypothesized that enchytraeids would release urea. ADMSW and CMSW were amended to pots
with sandy loam and barley. The pots were divided into treatments with or without mesofauna. Mesofauna, plant N and biomass,
soil N and ergosterol (fungal biomass) were measured over a 113-day period of four equidistant samplings. Soil respiration,
N mineralization and N release by the mesofauna were modelled from concurrent studies. ADMSW- and CMSW-treated soils initially
(<20 days) immobilized N. The amendments did not increase plant growth substantially, and this was probably due to N-limitation
in the early stages of plant growth. Enchytraeid abundance was about three times higher in ADMSW- than CMSW-treated soils,
indicating that ADMSW contained more labile compounds, bacteria, and microfauna. The mesofauna did not affect N-content, but
the cumulated -N excreted by the mesofauna was estimated to be substantial and about one-fifth of total plant N in ADMSW. An explanation
for this discrepancy might be that in the absence of the mesofauna, other members of the detrivore and microbivore community
performed the mesofauna’s function. Neither enchytraeids nor microarthropods excreted urea. 相似文献
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《中国生态农业学报》2014,(7)
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology, 相似文献
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《中国生态农业学报》2014,(6)
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology, 相似文献
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Grete Skrede Berit Karoline Martinsen Anne-Berit Wold Stein-Erik Birkeland Kjersti Aaby 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(3):193-208
Abstract A 3-year study was carried out to investigate quality parameters in 14 tree fruit and berry species grown in southern Norway. The species were blueberry, apple, aronia, sour cherry, sweet cherry, red raspberry, strawberry, blackcurrant, gooseberry, red currant and elderberry, harvested along with wild bilberry, cloudberry and lingonberry. Significant differences between species were identified for all quality parameters. The coefficient of variation between species was lowest for pH (12.5%), dry matter (18.9%) and soluble solids (25.3%), followed by titratable acids (59.3%), total phenolics (83.8%), antioxidant capacity FRAP (85.7%) and antiradical power by the DPPH-assay (97.8%), total monomeric anthocyanins (132%) and ascorbic acid (137%). Average coefficient of variation within species were lower and ranged from 4 (pH) to 62% (ascorbic acid). Only the FRAP values were significantly affected by harvesting year with lower levels in 2004 than in 2005 and 2006. There were significant interactions between species and harvesting year for dry matter, soluble solids, pH, ascorbic acid and FRAP. The results indicate generic ranges in composition within species independent upon growing location and climate, and the composition of the tree fruits and berries is not likely to deviate from these ranges. It is concluded that desirable composition of tree fruits and berries and their products should primarily be achieved by selection among species rather than searching fors broadened variation within individual species. 相似文献
20.
《Communications in Soil Science and Plant Analysis》2012,43(7):865-877
Potassium (K) fixation and release in soil are important factors in the long-term sustainability of a cropping system. Changes in K concentration and characteristics of K fixation and release in rhizosphere and nonrhizosphere soils in the rapeseed (Brassica napus L.)–rice (Oryza sativa L.) rotation were investigated using a rhizobox system. The concentrations of different forms of K in both rhizosphere and nonrhizosphere soils decreased with plants compared to without plants, regardless of K fertilizer application. Potassium uptake by crops mainly came from the rhizosphere soil. In the treatment without K fertilizer (–K), the main form of K supplied by the soil to the crops was 1.0 mol L?1 nitric acid (HNO3) nonextractable K, followed by nonexchangeable K, and then exchangeable K. In the treatment with K fertilizer (+K), the main K forms supplied by the soil to the crops were exchangeable K and nonexchangeable K. The amount and rate of K fixation after one cycle of the rapeseed–rice rotation was greater in rhizosphere soil than in nonrhizosphere soil. The amount and rate of K fixation of soil in the +K treatment were significantly less than in the –K treatment. The cumulative amounts of K released with 1.0 mol L?1 ammonium acetate (NH4OAc) and 1.0 mol L?1 HNO3 extraction increased with the increasing numbers of extractions, but the K-releasing power of soil by successive extraction decreased gradually and finally became almost constant. The release of K was less in rhizosphere soil than in nonrhizosphere soil. The release of K in the +K treatment was similar to that in the –K treatment in rhizosphere soil, but the K release in nonrhizosphere soil was greater with the +K than the –K treatment. Overall, the information obtained in this study will be helpful in formulating more precise K fertilizer recommendations for certain soils. 相似文献