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1.
往复切刀式小麦固定垄免耕播种机 总被引：7，自引：4，他引：3
针对西北灌溉农业区固定垄保护性耕作条件下玉米秸秆覆盖地垄作免耕播种小麦存在的机具堵塞、垄形破坏等问题,设计了一种集切茬、播种和修垄于一体的往复切刀式小麦固定垄免耕播种机。该机通过利用动力切刀往复垂直切茬和刀刃型开沟器水平切茬相结合的方式实现秸秆防堵,同时采用圆柱熟地型修垄犁解决垄形修复问题。田间试验表明,该机能有效地解决玉米秸秆堵塞问题,防堵能力强,修垄效果好;播种、施肥平均深度分别为46 mm和91 mm,均匀性好,可较好地满足西北灌溉农业区小麦垄作免耕播种的要求。 相似文献
2.
免耕播种机播种带玉米根茬处理装置研究 总被引：10，自引：5，他引：10
针对在有玉米根茬的未耕地上进行免耕直播时，播种机开沟器入土困难和容易堵草等问题，提出了新的切挖处理方案，研制出免耕播种机播种带玉米根茬处理装置，并对结构的关键参数进行了设计，提出了合理的工作参数。整机性能经田间生产试验结果表明，在有玉米根茬的未耕地上直接播种时，破茬入土能力强，扰土量少，可创造无根茬的良好种床条件，有利于种子生长发芽。 相似文献
3.
秸秆还田施肥点播机粉碎抛撒装置结构设计与优化 总被引：3，自引：3，他引：0
针对小麦秸秆粉碎还田免耕播种过程中出现的堵塞、架种与晾籽问题,该文对秸秆粉碎还田施肥点播机秸秆粉碎抛撒装置结构进行设计,采用理论分析、ADAMS仿真方法对切茬甩刀、切茬定刀、切茬粉碎机构与开沟器配合尺寸等秸秆粉碎抛撒装置关键参数进行设计,通过田间优化试验最终确定开沟器前侧至切茬甩刀水平位置端面距离为2.3 cm,秸秆挡板倾斜角为22°,此时晾籽率最低,为1.65%。作业性能验证试验表明:当整机的粉碎抛撒装置采用设计参数进行作业时,播深合格率为81.3%,秸秆粉碎长度合格率为96.6%,秸秆抛撒范围合格率为90.2%,秸秆抛撒不均匀度为11.9%,均优于标准要求,满足作业要求,试验过程全程无堵塞,点播机切茬粉碎抛撒装置可使秸秆全量还田同时保持机具良好通过性,实现免耕地无残茬播种并完成高质量秸秆粉碎抛撒盖种。本研究可为从秸秆粉碎抛撒角度解决堵塞问题、为免耕播种环境的相关机具研发提供参考。 相似文献
4.
针对长江中下游稻麦轮作区的稻茬地根茬量大韧性强、土壤黏度高不宜粉碎等问题，该研究基于仿真试验研制双轴破茬免耕装置。通过EDEM软件建立破茬开沟装置-秸秆-土壤离散元模型，采用正交试验得到破茬开沟装置的刀型、排列方式以及刀具数量，基于EDEM-ADAMS联合仿真，采用单因素试验、正交试验、二次回归正交旋转试验和响应曲面法对甩刀、粉碎装置以及双轴破茬免耕装置进行动力学分析，得到甩刀具参数、旋耕刀轴和粉碎刀轴转速以及双轴轴心水平与垂直高度，得到机具最佳参数：破茬装置选用30把旋耕刀采用双螺旋排列，刀轴转速为286 r/min；粉碎装置选用L型（32把）和直刀（8把）采用双螺旋排列，刀轴转速为605 r/min；双轴水平距离548 mm、垂直高度168 mm。根据最佳参数试制样机并进行田间性能测试。田间试验结果表明，秸秆和稻茬以0.93 kg/m2全量覆盖时，双轴破茬免耕装置对水稻秸秆、根茬的平均切断率以及切茬率分别为95.09%和95.16%，机具通过性良好，田间平均出苗率为95.29%，符合当地农艺要求，适用于秸秆覆盖量大的作业情况。所设计的双轴破茬免耕装置满足长江中下游稻麦轮作区小麦免耕播种作业要求，可为双轴旋转型耕作装置以及根茬不易粉碎、土壤黏度高条件下的免耕播种提供参考。 相似文献
5.
非对称式大小圆盘开沟装置设计与试验 总被引：4，自引：4，他引：0
为解决东北一年一熟区玉米秸秆覆盖地免耕播种玉米存在的秸秆覆盖量大导致机具堵塞严重和双圆盘开沟器入土困难等问题,该文设计了一种非对称式大小圆盘开沟装置,该装置采用大、小圆盘一前一后非对称设置,大圆盘预先切割秸秆、残茬,小圆盘完成秸秆拨离并开出种沟,为玉米免耕播种提供清洁种床。无秸秆覆盖下的EDEM离散元仿真试验和田间试验,预先验证了开沟装置的作业性能。秸秆覆盖下的田间试验表明:该装置在秸秆覆盖条件下仍可实现较为稳定可靠的开沟效果,平均开沟深度为71.41 mm,平均开沟宽度为38.27 mm,满足玉米免耕播种作业要求;不同秸秆覆盖条件下,该装置作业流畅、种沟整洁,无明显堵塞和连续晾仔、断条现象,切茬、入土性能良好。该研究可为玉米少免耕播种开沟装置的改进及研发提供理论支持和技术基础。 相似文献
6.
玉米免耕播种机主动式秸秆移位防堵装置的设计与试验 总被引：3，自引：7，他引：3
针对黄淮海麦玉轮作区小麦秸秆全量还田下苗床整备前存在多机具多次下田、生产成本高以及传统玉米免耕播种机在小麦秸秆全覆盖地作业时存在开沟壅堵、架种、晾种等问题,该文设计了一种基于"秸秆移位"防堵思路的主动式秸秆移位防堵装置。运用EDEM软件构建无支撑秸秆全覆盖土壤离散元模型,在秸秆-土壤-主动式防堵装置系统中进行秸秆移位虚拟仿真,设定了主动式秸秆移位防堵装置的刀轴驱动转速为500 r/min、回转半径为120 mm、刀盘幅宽为216 mm及刀齿入土深度为10 mm,利用仿真数据对秸秆扰动位移、清秸率进行分析,检验主动式秸秆移位防堵装置结构参数和运动参数设计的合理性。田间试验结果表明,安装主动式秸秆移位防堵装置的玉米免耕播种机的作业通过性稳定,改善种床环境,开沟壅堵次数为0次,秸秆清秸率为90.21%,相比仿真减少8.29个百分点。该研究可为小麦高留茬、秸秆全覆盖地的玉米免耕播种机的设计与推广提供参考。 相似文献
7.
免耕播种机驱动圆盘防堵单元体的设计与试验 总被引：10，自引：8，他引：2
一年两熟区前茬残留物多为玉米残茬,连同杂草易使免耕播种机播种冬小麦时造成开沟器堵塞。针对该问题,提出了驱动圆盘刀嵌入组合式开沟器联合防堵原理,设计了一种驱动圆盘式防堵单元体,并分析和确定了其主要结构参数。田间试验表明,驱动圆盘防堵单元体能够有效解决秸秆堵塞问题,保证小麦免耕播种机的通过性。与条带粉碎式小麦免耕播种机相比,驱动圆盘式小麦免耕播种机根茬切断率提高了11.2%,土壤扰动量减少了58.8%。在小麦返青期的苗情监测表明,与条带粉碎式小麦免耕播种和传统耕作播种相比,利用驱动圆盘式防堵单元体播种的免耕地,0～20 cm土壤层含水率最高,小麦分蘖数和次生根数最多,较好地满足一年两熟区农艺要求。 相似文献
8.
螺旋刀型垄台清理装置的设计与试验 总被引：4，自引：4，他引：0
针对现有玉米垄作免耕播种机存在的堵塞,功耗大,播种后种带存有大量秸秆影响播种质量等问题,研究设计了一种与玉米垄作免耕播种机配套使用的螺旋刀型垄台清理装置。在玉米秸秆覆盖垄作地试验结果表明,该装置的土壤扰动量约为18.3%～26%,秸秆覆盖率降低了35%～53%,能够满足免耕播种要求,有利于提高播种质量。相比条带旋耕式垄台清理装置,免耕播种机单位面积耗油量降低了13.8%,能够减少拖拉机的动力消耗。因此螺旋刀型垄台清理装置不仅解决了条带旋耕式垄台清理装置动力消耗大的问题,而且能够创造清洁的种床,对垄作保护性耕作技术的推广具有重要意义。 相似文献
9.
凹形圆盘式玉米垄作免耕播种机的设计与试验 总被引：11，自引：10，他引：1
针对东北垄作区免耕播种玉米存在的垄台清理效果差,机具堵塞严重,作业效率低等问题,设计了凹形圆盘式玉米垄作免耕播种机,研究了凹形圆盘式垄台清理装置,通过分析其运动特点,确定了其关键结构参数。在玉米秸秆覆盖的垄作地的试验结果显示,凹形圆盘式玉米垄作免耕播种机垄台清理效果好,能够有效防止秸秆堵塞,形成清洁种床。种肥间距为47 mm,均匀性好。土壤扰动量为22%,播种后种带秸秆覆盖率降低了75.9%,有利于提高苗期地温,改善播种质量,可较好满足东北垄作区玉米免耕播种的要求。 相似文献
10.
免耕播种机玉米根茬处理装置作业功耗试验研究（简报） 总被引：7，自引：7，他引：0
为找出影响免耕播种机玉米根茬处理装置的功率消耗的主次因素,对新研制的免耕播种机玉米根茬处理装置进行了室内土槽试验研究,对影响作业功耗的因素采用二次旋转回归正交试验,建立了玉米根茬处理装置的功耗模型.分析表明,在影响功率消耗的主要因素中,入土深度影响最大,其次是刀轴转速;机组前进速度、刀轴转速以及入土深度之间的交互作用对功率消耗的影响较小,单组根茬处理装置单组工作时功率消耗为1.55～2.35 kW.研究结果为开发新型免耕播种机以及选择配套动力提供理论依据. 相似文献
11.
【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
12.
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
13.
《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
14.
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
15.
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
16.
《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
17.
Electron donor and pH relationships for biologically enhanced dissolution of chlorinated solvent DNAPL in groundwater 总被引：3，自引：0，他引：3
Biologically enhanced dissolution offers a method to speed removal of chlorinated solvent dense non-aqueous-phase liquid (DNAPL) sources such as tetrachloroethene (PCE) and trichoroethene (TCE) from aquifers. Bioremediation is accomplished by adding an electron donor to the source zone where fermentation to intermediates leading to acetic acid and hydrogen results. The hydrogen and possibly acetic acid are used by dehalogenating bacteria to convert PCE and TCE to ethene and hydrochloric acid. Reductive dehalogenation is thus an acid forming process, and sufficient alkalinity must be present to maintain a near neutral pH. The bicarbonate alkalinity required to maintain pH above 6.5 is a function of the electron donor: 800 mg/L of bicarbonate alkalinity is sufficient to achieve about 1.2 mM TCE dechlorination with glucose, 1.7 mM with lactate, and a much higher 3.3 mM with formate. Laboratory studies indicate that in mixed culture, formate can be used as an electron donor for complete conversion to ethene, contrary to pure cultures studies indicating it cannot. Various strategies can be used to add electron donor to an aquifer for DNAPL dehalogenation while minimizing pH problems and excessive electron donor usage, including use of injection-extraction wells, dual recirculation wells, and nested injection-extraction wells. 相似文献
18.
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
19.
Three slow-growing legume trees used for desert reforestation and urban gardening in the Sonoran Desert of Northwestern Mexico
and the Southwestern USA were evaluated whether their growth can be promoted by inoculation with plant growth-promoting bacteria
(Azospirillum brasilense and Bacillus pumilus), unidentified arbuscular mycorrhizal (AM) fungi (mainly Glomus sp.), and supplementation with common compost under regular screenhouse cultivation common to these trees in nurseries. Mesquite
amargo (Prosopis articulata) and yellow palo verde (Parkinsonia microphylla) had different positive responses to several of the parameters tested while blue palo verde (Parkinsonia florida) did not respond. Survival of all tree species was over 80% and survival of mesquite was almost 100% after 10 months of cultivation.
Inoculation with growth-promoting microorganisms induced significant effects on the leaf gas exchange of these trees, measured
as transpiration and diffusive resistance, when these trees were cultivated without water restrictions. 相似文献
20.
Y. Bashan J. J. Bustillos L. A. Leyva J.-P. Hernandez M. Bacilio 《Biology and Fertility of Soils》2006,42(4):279-285
Inoculation of wheat seedlings with the plant growth-promoting bacterium Azospirillum brasilense Cd was immobilized in alginate microbeads and, without applying any stress, significantly increased the quantity of several
photosynthetic pigments, such as chlorophyll a, chlorophyll b, and the auxiliary photoprotective pigments violaxanthin, zeaxanthin, antheroxanthin, lutein, neoxanthin, and β-carotene.
This resulted in greener plants with no apparent visible stress. After monitoring the quantity of photosynthetic pigments
for 4 weeks, we observed that inoculated plants had higher quantities of pigments in shoot and stem. The greatest difference
in the quantity of all pigments between inoculated and noninoculated plants occurred in the first week of growth. Regardless
of treatment, the quantity of pigments in stems was three to four times less than the quantity of these pigments in shoots.
Application of Azospirillum, either as liquid inoculant or as alginate microbeads, did not alter the positive effect of the bacteria on pigment production
or the positive response of the plants towards A. brasilense Cd inoculation. 相似文献