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What Is the Impact of Ploughing on Eucalyptus Plantations in Bambou Mingali (Plateaux Batéké, Republic of Congo)?
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作者 Hugues-Yvan Gomat Darius Martin Bengo +5 位作者 Suspense Averti Ifo François Mankessi Josias Ossendza Prosper Mabiala Bernhard Zeller Laurent Saint-Andre 《Agricultural Sciences》 2024年第10期1132-1146,共15页
Soil ploughing is an important stage in the preparation of planting, causing disturbance to the physical, chemical and biological properties of the soil. Soil ploughing can affect the availability of nutrients and wat... Soil ploughing is an important stage in the preparation of planting, causing disturbance to the physical, chemical and biological properties of the soil. Soil ploughing can affect the availability of nutrients and water resources, and its effect can be short, medium or long-term. Soil ploughing accelerates surface heating and air circulation and encourages mineralisation by transforming organic matter into mineral salts, making nutrients soluble and accessible to plants. The aim of this study is to determine how soil ploughing affects the distribution of nutrients in the soil profile. The study focuses on nitrogen, carbon, phosphorus, calcium and magnesium, which are major elements of soil fertility on the Batéké plateaux in Congo. The results indicate that ploughing significantly modifies the distribution at depth des elements nutritifs: there is more accumulation at the surface than at depth (ei: nitrogen 1.34 t/ha ± 0.035 at 10 cm compared with 1.034 t/ha ± 0.098 at 50 cm) with a higher concentration of carbon (13.89 t/ha ± 0.87) followed by nitrogen (1.34 t/ha ± 0.035). 展开更多
关键词 ploughING MINERALIZATION EUCALYPTUS Plateaux Batéké CONGO
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FEM analysis of workpiece curvature influence on groove deformation during plough process 被引量:2
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作者 陆龙生 刘晓辰 +1 位作者 汤勇 袁冬 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第7期1738-1743,共6页
To investigate the workpiece curvature influence on groove deformation,numerical studies with curvature varying from negative to positive were conducted on copper material.Groove deformations were analyzed,including g... To investigate the workpiece curvature influence on groove deformation,numerical studies with curvature varying from negative to positive were conducted on copper material.Groove deformations were analyzed,including groove geometry,effective stress distribution and plough force.The curled groove shape whose workpiece curvature was 0.133 mm-1 was validated by experiments.Moreover,a series of geometry models with various curvatures were introduced to analyze the change of groove deformation.The results show that positive curvatures influence groove deformation more intensively than negative or zero curvature.It is mainly due to the action of the tool forming face during plough process. 展开更多
关键词 plough workpiece curvature microgroove MICROCHANNEL finite element method
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Reducing Operation Emissions and Improving Work Efficiency Using a Pure Electric Wheel Drive Tractor 被引量:1
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作者 Chang-Kai Wen Wen Ren +5 位作者 Qing-Zhen Zhu Chun-Jiang Zhao Zhen-Hao Luo Sheng-Li Zhang Bin Xie Zhi-Jun Meng 《Engineering》 SCIE EI CAS CSCD 2024年第6期230-245,共16页
In response to the problems of excessive greenhouse-gas and particulate emissions and the low traction efficiency of conventional diesel tractors in the field,a purely electric wheel-side drive tractor was studied,inc... In response to the problems of excessive greenhouse-gas and particulate emissions and the low traction efficiency of conventional diesel tractors in the field,a purely electric wheel-side drive tractor was studied,including an electric motor drive system,a battery ballast system,and an electro–hydraulic suspension system.This paper develops a dynamics model of an electric tractor-ploughing unit under complex soil conditions,leading to the proposal of an active control method for drive wheel torque and a joint control method for the traction force of the suspension system and the front-and rear-axle loads of a tractor.Finally,the tractor is prototyped and assembled,and ploughing tests are carried out.The ploughing results show that the active torque-distribution control method proposed in this study reduces the tractor slip by 14.83%and increases the traction efficiency by 10.28%compared with the average torquedistribution mode.Compared with the conventional traction control mode,the joint control method for traction and ballast proposed in this paper results in a 3.7%increase in traction efficiency,a 15.05%decrease in slip,and a 4.9%reduction in total drive motor energy consumption.This study will help to improve the operation quality and traction efficiency of electric tractors in complex soil conditions. 展开更多
关键词 Electric tractor ploughing unit Torque distribution Active ballast Traction performance
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Reconstruction of Highly-efficient Smash-ridging Ecological Cultivation Method for Sustainable Yield-increasing of Soil Plough Layers 被引量:4
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作者 韦本辉 《Agricultural Science & Technology》 CAS 2014年第9期1526-1529,共4页
With consideration of highly-efficient use of natural resources, reducing production cost and construction of high-standard agricultural fields, rice production of good seed+fertilizer investment is reformed on basis... With consideration of highly-efficient use of natural resources, reducing production cost and construction of high-standard agricultural fields, rice production of good seed+fertilizer investment is reformed on basis of research of smash-ridging technology, and rice smash-ridging ecological and highly-efficient cultivation was pro- posed, namely, smash-ridging based deeply poughing and rotary tillage technology was used to loosen soils deeply, with the depth from 13-15 cm to 26-28 cm. Fur- thermore, after soils softening, seedling slinging or direct seeding was adopted, which is dominated by natural rainfall and supplemented by artificial irrigation. The test proved that the technology help increasing yield and profits over 20%, with chemical fertilizer reduced by more than 10%, and labor cost reduced by 10%. What's more, if the technology applied once, no-tillage or slight tillage is recom- mended in the field, which would maintain original eco-conditions of soils and reach high yield, with energy, water, labor costs reduced in an environment-friendly way. 展开更多
关键词 Powder ridge plough layer reconstruction Ecological cultivation Sus- tainable yield-increasinq by 20% Rice
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Effects of Ploughing Astragalus sinicus at Maturity Stage on Rice Yield and Soil Properties of Paddy Field
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作者 王伯诚 赖小芳 +2 位作者 陈银龙 项玉英 陈剑 《Agricultural Science & Technology》 CAS 2013年第12期1792-1796,1803,共6页
[Objective] The effects of ploughing Astragalus sinicus at maturity stage as green manure on paddy soil properties were studied to provide references for ad- vancing the green manure production and field sustainable d... [Objective] The effects of ploughing Astragalus sinicus at maturity stage as green manure on paddy soil properties were studied to provide references for ad- vancing the green manure production and field sustainable development. [Methods] A three-year field positioning experiment was carried out. In the first year, five differ- ent levels (0, 2.81, 5.61, 8.42, 11.23 t/hm~) of Astragalus sinicus ploughed at matu- rity stage were designed. And in the next two years, the amounts of ploughed As- tragalus sinicus at maturity stage were based on the natural growth amounts of As- tragalus sinicus at maturity stage of the former year in each plot field. The yields of Astragalus sinicus at maturity stage were estimated and ploughed directly before rice transplanting. Rice yield, soil nutrients, biological properties and water-stable aggre- gates of paddy fields were measured as well. [Results] The effective panicles and rice yields increased significantly after ploughing Astragalus sinicus at maturity stage. Meanwhile, the organic acid content in paddy field increased and the activities of soil phosphatases, invertase and catalase were higher. The soil dissolved organic carbon also increased with the increasing application of green manure. However, excess amount of green manure inhibited the soil microbial biomass carbon content. The macro aggregates and micro aggregates gathered to middle aggregates. [Conclusion] As green manure, the use of Astragalus sinicus at maturity stage could improve soil physiochemical and biological properties, improve soil fertility and increase rice yield significantly. But the ploughing amount of Astragalus sinicus at maturity stage before rice transplanting should be less than 8.42 t/hm2 (dry weight. 展开更多
关键词 Astragalus sinicus at maturity stage ploughING Rice yield Paddy soil nutrients Soil properties
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Fin formation model during pre-roll ploughing of copper 3D outside fin tube 被引量:15
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作者 汤勇 夏伟 +2 位作者 曾志新 刘树道 叶帮彦 《中国有色金属学会会刊:英文版》 CSCD 2001年第5期712-716,共5页
The mechanism of pre roll ploughing for 3D fins on the outside surface of copper tube was studied systematically, and especially the process and conditions of 3D fin formation were analyzed. The right mathematical mod... The mechanism of pre roll ploughing for 3D fins on the outside surface of copper tube was studied systematically, and especially the process and conditions of 3D fin formation were analyzed. The right mathematical model was also established. Based on the volume of fin ploughed out is equal to the volume of the metal extruded up by the extruding face of the tool, the relations between fin height, pre roll ploughing feed and pre roll ploughing depth have been achieved. With the increase of pre roll ploughing depth which must be equal to groove depth, the fin height gradually becomes larger. There are different critical feeds with the various depths of pre roll ploughing. The pre roll ploughing feed is the critical one, the height of fin is largest. And when the feed is above the critical one, the fin height will reduce with the increase of feed. The theoretical analysis basically accords with experimental results. 展开更多
关键词 pre roll ploughing copper 3D outside fin tube heat transfer
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Mathematical model of electric hydraulic and powered support control system at a plough mining face 被引量:2
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作者 ZHANG Wei HAN Xiao SUN Jing-jing 《Journal of China University of Mining and Technology》 EI 2008年第1期55-58,共4页
Given the actual working of a fully mechanized plough at a mining face, we have proposed a formula for running constraints between powered supports and a coal plough under assumed geological conditions of the coal fac... Given the actual working of a fully mechanized plough at a mining face, we have proposed a formula for running constraints between powered supports and a coal plough under assumed geological conditions of the coal face and, on this basis, established an automatic control model of powered supports for the coal plough face. We introduced the working principle of the powered support control system of the plough at the mining face. We established three advanced characteristics of this control system: response speed, reliability and easy maintenance of the system. As well, we briefly introduced, the principal function of primary and subordinate controllers and the realization of the communication system by a Single Bus. Ten controllers were constructed and tested in our laboratorium. The results show that the control model is practical and meets actual conditions. It provides a theoretical basis for designing a comouter control system for a oowered support system of a plough at a mining face. 展开更多
关键词 plough mining face powered supports CONSTRAINTS automatic control model
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Effect of plough pans on the growth of soybean roots in the black-soil region of northeastern China 被引量:1
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作者 DONG Wen-cai FU Qiang +1 位作者 WANG Quan-jiu CAO Cheng-peng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第10期2191-2196,共6页
Plough pans (PPs), common in the black-soil region of northeastern China, have significant effects on the root systems of crops. We conducted a field experiment to study the distribution of soybean roots under the i... Plough pans (PPs), common in the black-soil region of northeastern China, have significant effects on the root systems of crops. We conducted a field experiment to study the distribution of soybean roots under the influence of PPs. The soybean roots showed compensatory growth above the PP, with higher root length and weight in soil with a PP compared to those without a PP. Roots were heavier and longer in the 15-75 cm soil layer without a PP than with a PP. Soil porosity was lower in the PP and the soil below the PP, which likely decreased the oxygen content of the soil and induced more growth of roots above the PP. The PP is also likely to decrease infiltration of rain-water and hinder the migration of nitrate downward, which in turn increased the density and length of soybean root hairs, which, hence, promoted growth. 展开更多
关键词 compensatory growth plough pans root characteristics SOYBEAN
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Effect of Ploughing Depth on the Growth and Yield of Heracleum candicans:a Threatened Medicinal Herb and a Less-explored Potential Crop of the Himalayan Region 被引量:1
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作者 Hemant K. Badola Jitendra S. Butola 《Journal of Mountain Science》 SCIE CSCD 2005年第2期173-180,共8页
This paper examines the effect of ploughing depths (A -- 60 cm, B -- 45 cm and C -- 30 cm) on the growth and yield of Heracleum candicans Wall (Apiaceae), a threatened medicinal herb of the Himalayan region. This ... This paper examines the effect of ploughing depths (A -- 60 cm, B -- 45 cm and C -- 30 cm) on the growth and yield of Heracleum candicans Wall (Apiaceae), a threatened medicinal herb of the Himalayan region. This less-explored plant is being suggested as a potential crop for the mountain agriculture. The study was carried out in an orchard in Himachal Pradesh, India at 2500 m altitude, for two successive growth years. During the first year, all plants remained in juvenile state; in the second year, nearly 65 % plants produced flowers only under 60cm ploughing depth. Among its morphological traits, plant height, collar diameter and aboveground flesh weight were found to be strongly correlated (P 〈 0.01) with the belowground biomass during the first year (r =0.968, 0.925 and 0.973, respectively) and during the second year (r=0.945, 0.928 and 0.775, respectively). Increase in the ploughing depth was significantly correlated (P〈0.01) with all growth parameters, including the belowground dry weight, marketable portion of the produce. The belowground biomass (commercial yield; 16.28 Qt/hec) at depth A was about 2.6 and 4.7 times higher than those recorded at depths B and C, respectively. The results clearly justify the importance of deep ploughing and this paper strongly recommends it for economically sustainable cropping. 展开更多
关键词 CROP Heracleum candicans medicinal herb morphological traits ploughing depth yield mountain agriculture Patrala
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Analysis and Research of Factors Affecting Coal Mining with Plough 被引量:1
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作者 刘过兵 陈胜利 《Journal of China University of Mining and Technology》 2002年第2期190-193,共4页
Coal mining with ploughs is an ideal coal mining technology for thin and thinner coal seams. The existence conditions of coal seams are different for each other, which affects coal mining with ploughs to different deg... Coal mining with ploughs is an ideal coal mining technology for thin and thinner coal seams. The existence conditions of coal seams are different for each other, which affects coal mining with ploughs to different degrees, and the application results are also different. The authors analyze the affecting factors by means of mathematical methods. The research is useful to the wide application of ploughs. 展开更多
关键词 coal mining with plough affecting factor ANALYSIS
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Design and Experiment of 1LFQ-325 Pneumatic Reversible Plough
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作者 Xuan ZHENG Xuefeng CHEN +1 位作者 Chaomin QIN Li JIAbo JIA 《Asian Agricultural Research》 2013年第1期76-78,82,共4页
A pneumatic reversible plough is developed, which complements to the tractor of 25.7-36.8 kW.The plough adopts the cylinder as reversing mechanism between the right and left plough bodies, and the cylinder can substit... A pneumatic reversible plough is developed, which complements to the tractor of 25.7-36.8 kW.The plough adopts the cylinder as reversing mechanism between the right and left plough bodies, and the cylinder can substitute the mechanical reversing mechanism. The pneumatic turnover allows the plough to be operated easily and turned over flexibly. Field experiment results show that indicators of plough performance meet the requirements of the relevant national standards. 展开更多
关键词 PNEUMATIC REVERSIBLE plough DESIGN EXPERIMENT
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FDA批准Schering—Plough公司联合Pegintron和Rebetol用于治疗丙型肝炎的标签修订
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《世界临床药物》 CAS 2008年第5期258-258,共1页
FDA已批准先灵葆雅公司(Schering-Plough)聚乙二醇干扰素α-2b(Pegintron)和利巴韦林(Rebetol)联合治疗丙型肝炎的说明书修订。其修订内容如下:原有说明书中Rebetol的推荐剂量由一日800mg修订为一日800-1400mg(且可根据患者的... FDA已批准先灵葆雅公司(Schering-Plough)聚乙二醇干扰素α-2b(Pegintron)和利巴韦林(Rebetol)联合治疗丙型肝炎的说明书修订。其修订内容如下:原有说明书中Rebetol的推荐剂量由一日800mg修订为一日800-1400mg(且可根据患者的体重进行具体的剂量调整), 展开更多
关键词 Rebetol FDA批准 修订内容 plough公司 丙型肝炎 联合治疗 聚乙二醇干扰素Α 标签
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EMEA接受Schering-Plough的生育治疗药的申报
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《国外药讯》 2009年第2期12-12,共1页
Schering—Plough公司的一次注射,持续性卵泡刺激剂corifollitropin α(Ⅰ)的上市许可证申请已为EMEA接受审查。该公司称它近期没有将(Ⅰ)向其他任何市场申请的计划,也未推测进一步申报的潜在时机。
关键词 EMEA 申报 治疗药 plough公司 生育 刺激剂 持续性 许可证
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Schering—Plough的sugammadex获得优先审核
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作者 唐志坚(摘) 《国外药讯》 2008年第5期27-27,共1页
美国FDA给了Schering—Plough公司的新型选择性肌松结合药Sugammadex(sugammadex sodium)优先审核地位。公司希望能够在今年第二季度得到FDA的决定。申请的依据是1700多名患者参加的10项全球性Ⅲ期试验,与向EU申请的文件是相同的。E... 美国FDA给了Schering—Plough公司的新型选择性肌松结合药Sugammadex(sugammadex sodium)优先审核地位。公司希望能够在今年第二季度得到FDA的决定。申请的依据是1700多名患者参加的10项全球性Ⅲ期试验,与向EU申请的文件是相同的。EMEA在去年7月已接受该药进行审核。Schering—Plough在11月收购Organon Biosciences时得到该产品。 展开更多
关键词 审核 plough公司 美国FDA Ⅲ期试验 EMEA
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呼吸系统、特殊感官及皮肤用药——Schering—Plough公司申请哮喘合剂
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《国外药讯》 2009年第11期16-17,共2页
欧洲医药管理局(EMEA)已同意审查Schering—Plough公司通过欧盟集中程序申请的皮质激素Asmanex(mometasone furoate,糠酸莫米松)(Ⅰ)与Norvartis公司的长效B2激动剂Foradil(formoterol fumarate,富马酸福莫特罗)(Ⅱ)的固定... 欧洲医药管理局(EMEA)已同意审查Schering—Plough公司通过欧盟集中程序申请的皮质激素Asmanex(mometasone furoate,糠酸莫米松)(Ⅰ)与Norvartis公司的长效B2激动剂Foradil(formoterol fumarate,富马酸福莫特罗)(Ⅱ)的固定剂量吸入性合剂(Ⅲ)用于12岁及12岁以上的哮喘患者作维持治疗的上市许可证。 展开更多
关键词 plough公司 哮喘合剂 呼吸系统 皮肤用药 特殊感官 FUMARATE 富马酸福莫特罗 糠酸莫米松
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抗感染药——Schering—Plough从富山转让garenoxacin的权利
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作者 李卫华 《国外药讯》 2004年第6期25-25,共1页
关键词 抗感染药 Schering—plough 富山 转让权利 GARENOXACIN 喹诺酮类抗菌药
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呼吸系统、特殊感官及皮肤用药-S Plough公司获得Asmanex/Foradil的全球独占权
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《国外药讯》 2009年第7期18-19,共2页
美国Schering-Plough公司更改了它与Novartis签署的开发协议条款,重点放在气喘和慢性阻塞性肺病(COPD)药物方面。现在S-P公司(正处于被Merck公司收购的谈判过程)获得它的吸人皮质类固醇Asmanex(mometasortefuroate,糠酸莫米松)... 美国Schering-Plough公司更改了它与Novartis签署的开发协议条款,重点放在气喘和慢性阻塞性肺病(COPD)药物方面。现在S-P公司(正处于被Merck公司收购的谈判过程)获得它的吸人皮质类固醇Asmanex(mometasortefuroate,糠酸莫米松)吸入粉剂和Novartis公司的长效beta 2-肾上腺素能受体激动剂Foradil(formoterol,福莫特罗)固定剂量复方的全球独占权。 展开更多
关键词 plough公司 呼吸系统 皮肤用药 特殊感官 慢性阻塞性肺病 Merck公司 皮质类固醇 糠酸莫米松
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GYANTSE SPRING PLOUGHING CEREMONY
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作者 Wang Hong 《China's Tibet》 2007年第3期65-,共1页
With a total of 765.6 hectares of plowed land,Kharmey Township is the principal place for grain production in Gyantse.Villagers, including both men and women,old or young and dressed in festival costumes,are crowding ... With a total of 765.6 hectares of plowed land,Kharmey Township is the principal place for grain production in Gyantse.Villagers, including both men and women,old or young and dressed in festival costumes,are crowding together at the edge of the field in the early morning;they place buttered tea, barley yeasted wine,sutra steamers, and incense burners for prayers 展开更多
关键词 GYANTSE SPRING ploughING CEREMONY
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华北玉麦两熟区犁式秸秆翻埋装置参数优化
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作者 张明 王景政 +4 位作者 张秀花 弋景刚 白占欣 卢占喜 赵西哲 《农机化研究》 北大核心 2023年第8期130-136,共7页
华北玉麦两熟地区玉米收获后土壤表面秸秆量大,传统还田作业效果不理想,且长期的旋耕和免耕作业导致土地形成了犁底层和土壤板结,影响小麦播种作业及土地的可持续发展利用。为此,综合考虑秸秆还田和打破犁底层等问题,设计了用于华北玉... 华北玉麦两熟地区玉米收获后土壤表面秸秆量大,传统还田作业效果不理想,且长期的旋耕和免耕作业导致土地形成了犁底层和土壤板结,影响小麦播种作业及土地的可持续发展利用。为此,综合考虑秸秆还田和打破犁底层等问题,设计了用于华北玉麦两熟区整地机的翻埋装置,并对装置进行参数优化。利用离散元仿真技术、数字化土槽与田间试验相结合的方法,对整地机的翻埋装置进行分析优化。试验结果表明:秸秆翻埋率为97.4%,耕深稳定性系数为91.35%,性能稳定,满足小麦播种要求。 展开更多
关键词 秸秆翻埋 整地机 离散元仿真 玉麦两熟区 犁底层
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Effects of Root Growth of Deep and Shallow Rooting Rice Cultivars in Compacted Paddy Soils on Subsequent Rice Growth
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作者 Md.Dhin ISLAM Adam H.PRICE Paul D.HALLETT 《Rice science》 SCIE CSCD 2023年第5期459-472,I0022-I0024,共17页
Rice is often grown as multiple seasons in one year,alternating between flooded and upland systems.A major constraint,introduced from the flooded system,is a plough pan that may decrease rooting depth and productivity... Rice is often grown as multiple seasons in one year,alternating between flooded and upland systems.A major constraint,introduced from the flooded system,is a plough pan that may decrease rooting depth and productivity of follow-on upland rice.Roots penetrating the plough pan under flooded rice system can leave a legacy of weaker root growth pathways.Deeper rooting rice cultivars could have a bigger impact,but no direct evidence is available.To explore whether a deep rather than a shallow rooting rice cultivar grown in a flooded cropping cycle benefited deeper root growth of follow-on rice in an upland,reduced tillage cropping cycle,a simulated flooded paddy in greenhouse was planted with deep(Black Gora) and shallow(IR64) rooting cultivars and a plant-free control.Artificial plough pans were made in between the topsoil and subsoil to form different treatments with no plough pan(0.35 MPa),soft plough pan(1.03 MPa) and hard plough pan(1.70 MPa).After harvest of this ‘first season’ rice,the soil was drained and undisturbed to simulate zero-tillage upland and planted rice cultivar BRRI Dhan 28.The overall root length density(RLD),root surface area,the numbers of root tips and branching of BRRI Dhan 28 did not vary between plough pan and no plough pan treatments.Compared with the shallow rooting rice genotype,the deep rooting rice genotype as ‘first season’ crop produced 19% greater RLD,34% greater surface area and 29% more branching of BRRI Dhan 28 in the subsoil.In the topsoil,however,BRRI Dhan 28 had 28% greater RLD,35% greater surface area and 43% more branching for the shallow rather than deep rooting genotype planted in the ‘first season’.The results suggested that rice cultivar selection for a paddy cycle affects root growth of a follow-on rice crop grown under no-till,with benefits to subsoil access from deep rooting cultivars and topsoil proliferation for shallow rooting cultivars. 展开更多
关键词 plough pan root growth biopores crop rotation Oryza sativa preceding crop ZERO-TILLAGE
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