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Grain yield and N uptake of maize in response to increased plant density under reduced water and nitrogen supply conditions

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Journal of Integrative Agriculture 2024年第1期23卷 122-140页

作者： Jingui Wei Qiang Chai Wen Yin Hong Fan Yao Guo falong hu Zhilong Fan QimingWang State Key Laboratory of Aridland Crop Science Lanzhou 730070China College of Agronomy Gansu Agricultural UniversityLanzhou 730070China College of Life Sciences Northwest Normal UniversityLanzhou 730070China

The development of modern agriculture requires the reduction of water and chemical N fertilizer *** the planting density can maintain higher yields,but also consumes more of these restrictive ***,whether an increased maize density can compensate for the negative effects of reduced water and N supply on grain yield and N uptake in the arid irrigated areas remains *** study is part of a long-term positioning trial that started in 2016.A split-split plot field experiment of maize was implemented in the arid irrigated area of northwestern China in 2020 to *** treatments included two irrigation levels:local conventional irrigation reduced by 20%(W1,3,240 m^(3)ha^(-1))and local conventional irrigation(W2,4,050 m^(3)ha^(-1));two N application rates:local conventional N reduced by 25%(N1,270 kg ha^(-1))and local conventional N(360 kg ha^(-1));and three planting densities:local conventional density(D1,75,000 plants ha^(-1)),density increased by 30%(D2,97,500 plants ha-1),and density increased by 60%(D3,120,000 plants ha^(-1)).Our results showed that the grain yield and aboveground N accumulation of maize were lower under the reduced water and N inputs,but increasing the maize density by 30% can compensate for the reductions of grain yield and aboveground N accumulation caused by the reduced water and N *** water was reduced while the N application rate remained unchanged,increasing the planting density by 30% enhanced grain yield by 13.9% and aboveground N accumulation by 15.3%.Under reduced water and N inputs,increasing the maize density by 30% enhanced N uptake efficiency and N partial factor productivity,and it also compensated for the N harvest index and N metabolic related enzyme *** with W2N2D1,the N uptake efficiency and N partial factor productivity increased by 28.6 and 17.6%under W1N1D2.W1N2D2 had 8.4% higher N uptake efficiency and 13.9% higher N partial factor productivity than W2N2D1.W1N2D2 improv

关键词： water and N reduction plant density maize grain yield N uptake compensation effect

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Legume green manure can intensify the function of chemical nitrogen fertilizer substitution via increasing nitrogen supply and uptake of wheat

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The Crop Journal 2024年第4期12卷 1222-1232页

作者： Jingui Wei Zhilong Fan falong hu Shoufa Mao Fang Yin Qiming Wang Qiang Chai Wen Yin State Key Laboratory of Arid Land Crop Science Lanzhou 730070GansuChina College of Agronomy Gansu Agricultural UniversityLanzhou 730070GansuChina

Achieving the green development of agriculture requires the reduction of chemical nitrogen(N)fertilizer *** studies have confirmed that returning green manure to the field is an effective measure to improve crop yields while substituting partial chemical N ***,it remains unclear how to further intensify the substituting function of green manure and elucidate its underlying agronomic *** a split-plot field experiment in spring wheat,different green manures returned to the field under reduced chemical N supply was established in an oasis area since 2018,in order to investigate the effect of green manure and reduced N on grain yield,N uptake,N use efficiency(NUE),N nutrition index,soil organic matter,and soil N of wheat in *** results showed that mixed sown common vetch and hairy vetch can substitute 40%of chemical N fertilizer without reducing grain yield or N ***,mixed sown common vetch and hairy vetch under reduced N by 20%showed the highest N agronomy efficiency and recovery efficiency,which were 92.0%and 46.0%higher than fallow after wheat harvest and conventional N application rate,*** increase in NUE of wheat was mainly attributed to mixed sown common vetch and hairy vetch,which increased N transportation quantity and transportation rate at pre-anthesis,enhanced N harvest index,optimized N nutrition index,and increased activities of nitrate reductase and glutamine synthetase of leaf,***,mixed sown common vetch and hairy vetch under reduced N by 20%improved soil organic matter and N ***,mixed sown common vetch and hairy vetch can substitute 40%of chemical N fertilizer while maintaining grain yield and N accumulation,and it combined with reduced chemical N by 20%or 40%improved NUE of wheat via enhancing N supply and uptake.

关键词： Legume green manure Reduced N input Wheat N uptake and supply Agronomic mechanism

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Determination of the Minimum Testing Time for Wireline Formation Testing with the Finite Element Method

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Petroleum Science 2006年第1期3卷 39-44页

作者： hu falong Xiao Lizhi Zhang Yuanzhong Wang Chengwei Faculty of Natural Resource ＆ Information Technology China University of Petroleum Beijing 102249 China China Petroleum Engineering ＆ Construction （Group） Corp. Beijing 100011 China

The wireline formation tester （WFT） is an important tool for formation evaluation, such as calculating the formation pressure and permeability, identifying the fluid type, and determining the interface between oil and water. However, in a low porosity and low permeability formation, the supercharge pressure effect exists, since the mudcake has a poor sealing ability. The mudcake cannot isolate the hydrostatic pressure of the formation around the borehole and the mud seeps into the formations, leading to inaccurate formation pressure measurement. At the same time, the tool can be easily stuck in the low porosity/low permeability formation due to the long waiting and testing time. We present a method for determining the minimum testing time for the wireline formation tester. The pressure distribution of the mudcake and the formation were respectively calculated with the finite element method （FEM）. The radius of the influence of mud pressure was also computed, and the minimum testing time in low porosity/low permeability formations was determined within a range of values for different formation permeabilities. The determination of the minimum testing time ensures an accurate formation pressure measurement and minimizes possible accidents due to long waiting and testing time.

关键词： Wireline formation tester the minimum testing time the finite element method

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Yield photosynthesis and leaf anatomy of maize in inter-and mono-cropping systems at varying plant densities

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The Crop Journal 2022年第3期10卷 893-903页

作者： Hongwei Yang Qiang Chai Wen Yin falong hu Anzhen Qin Zhilong Fan Aizhong Yu Cai Zhao Hong Fan State Key Laboratory of Arid Land Crop Science Lanzhou 730070GansuChina College of Agronomy Gansu Agricultural UniversityLanzhou 730070GansuChina Institute of Farmland Irrigation Chinese Academy of Agricultural Sciences/Key Laboratory of Crop Water Use and RegulationMinistry of Agriculture and Rural AffairsXinxiang 453002HenanChina

Increasing plant density can increase cereal crop yields. However, the physiological and anatomical mechanisms of grain yield increase at high plant densities in maize-based intercropping systems are not well understood. A two-year field experiment was conducted in 2018 and 2019 to investigate grain yield, photosynthetic characteristics, stomatal traits, and leaf anatomy of maize plants in an intercropping system with high plant densities. Two cropping patterns(monocropping and intercropping) and three plant densities(D1, 78,000 plants ha^(-1);D2, 103,500 plants ha^(-1);D3, 129,000 plants ha;were arranged in a randomized block design. Increasing maize plant density significantly increased maize yield, and intercropping gave a significant yield advantage over monocropping under the same plant density. Intercropping combined with high plant density increased the leaf area and SPAD value of maize,increasing the photosynthesis rates after the harvest of pea. At the twelfth leaf stage, the stomatal density and stomatal area of intercrops combined with medium plant density increased by respectively 10.5%and 18.4% relative to their values for the corresponding density of monocrops. Although leaf thickness of maize was reduced by increasing plant density, the chloroplast number and grana lamella number were higher in intercropping than in monocropping under different plant densities. These positive changes in leaf anatomy resulted in increased photosynthesis, suggesting a physiological basis for the increase in grain yield.

关键词： Maize/pea intercropping Plant density Leaf area Photosynthesis Leaf anatomy

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An unsupervised clustering method for nuclear magnetic resonance transverse relaxation spectrums based on the Gaussian mixture model and its application

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Petroleum Exploration and Development 2022年第2期49卷 339-348页

作者： GE Xinmin XUE Zong’an ZHOU Jun hu falong LI Jiangtao ZHANG Hengrong WANG Shuolong NIU Shenyuan ZHAO Ji’er School of Geosciences China University of PetroleumQingdao 266580China CNPC Key Well Logging Laboratory Xi’an 710077China Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071China Oil and Gas Survey Center of China Geological Survey Beijing 100083China China Petroleum Logging Co.Ltd. Xi’an 710077China PetroChina Research Institute of Petroleum Exploration&Development Beijing 100083China PetroChina Qinghai Oilfield Company Dunhuang 736202China Zhanjiang Branch of CNOOC Ltd. Zhanjiang 524057China Sinopec Research Institute of Petroleum Engineering Beijing 100101China

To make the quantitative results of nuclear magnetic resonance(NMR) transverse relaxation(T;) spectrums reflect the type and pore structure of reservoir more directly, an unsupervised clustering method was developed to obtain the quantitative pore structure information from the NMR T;spectrums based on the Gaussian mixture model(GMM). Firstly, We conducted the principal component analysis on T;spectrums in order to reduce the dimension data and the dependence of the original variables. Secondly, the dimension-reduced data was fitted using the GMM probability density function, and the model parameters and optimal clustering numbers were obtained according to the expectation-maximization algorithm and the change of the Akaike information criterion. Finally, the T;spectrum features and pore structure types of different clustering groups were analyzed and compared with T;geometric mean and T;arithmetic mean. The effectiveness of the algorithm has been verified by numerical simulation and field NMR logging data. The research shows that the clustering results based on GMM method have good correlations with the shape and distribution of the T;spectrum, pore structure, and petroleum productivity, providing a new means for quantitative identification of pore structure, reservoir grading, and oil and gas productivity evaluation.

关键词： NMR T2 spectrum Gaussian mixture model expectation-maximization algorithm Akaike information criterion unsupervised clustering method quantitative pore structure evaluation

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保护性耕作对小麦/玉米间作系统生产效率和可持续性的影响

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中国生态农业学报（中英文） 2019年第9期27卷 1344-1353页

作者：王琦明胡发龙柴强甘肃农业大学资源与环境学院兰州730070 甘肃农业大学农学院兰州730070 甘肃省干旱生境作物学重点实验室兰州730070

农田复合系统是集约化农作的有效途径之一,在增加生物多样性和提高产量方面具有重要作用。干旱区农业生产中,温室气体减排和作物耗水减量是发展高效可持续农业的重要参考指标,研发基于作物复合生产的模式是该区节水、减排和可持续农业... 详细信息

农田复合系统是集约化农作的有效途径之一,在增加生物多样性和提高产量方面具有重要作用。干旱区农业生产中,温室气体减排和作物耗水减量是发展高效可持续农业的重要参考指标,研发基于作物复合生产的模式是该区节水、减排和可持续农业发展面临的重大课题。本研究以河西绿洲灌区长期规模化种植的小麦/玉米复合生产系统为对象,于2010 2012年度在甘肃农业大学校地联合绿洲农业科研教学基地(武威站),通过集成免耕立茬(NTS)、免耕秸秆覆盖(NTM)、少耕秸秆翻压(RTS)形成不同小麦/玉米间作复合系统,并以传统间作(CTI)为对照,重点研究了不同系统的土壤碳排放量和水分利用特征,比较分析了其生产效率和可持续性。结果表明,小麦和玉米复合系统的生物热能产较单作小麦提高113%,较单作玉米提高21%,该系统基于生物热能产的土地当量比均大于1。农田复合生产系统能有效降低土壤CO2排放,特别是集成免耕秸秆覆盖的间作系统,土壤CO2排放量比单作玉米降低12%,比传统间作降低13%,排放效率比单作玉米提高39%,比传统间作提高31%。此外,农田复合生产系统还显著降低了作物耗水,与传统间作相比,集成免耕秸秆覆盖的间作系统的棵间蒸发量、耗水总量和单位耗水碳排放量分别降低11%、5%和9%,但单位耗水生物热能产提高19%。农田复合生产系统较传统间作具有更高的土地当量比(1.78)、碳排当量比(1.48)和耗水当量比(1.22),三者分别提高14%、28%和20%,因而其可持续评价指数提高了13%。小麦/玉米间作集成免耕秸秆覆盖的农田复合生产系统可作为河西绿洲灌区高效可持续农作的可行模式。

关键词：小麦/玉米间作保护性耕作土壤CO2排放水分利用生物热能产

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少耕轮作小麦间作玉米的产量表现和水分利用效率

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西北农业学报 2013年第6期22卷 47-52页

作者：殷文柴强胡发龙甘肃省干旱生境作物学重点实验室甘肃农业大学农学院兰州730070

通过田间定位试验,研究少耕轮作和小麦秸秆覆盖方式对小麦间作玉米产量和水分利用效率的影响。结果表明,少耕轮作和留茬覆盖小麦间作玉米具有明显的增产和提高水分利用效率(WUE)的作用。一个轮作周期内,间作轮作中小麦籽粒产量较相应单... 详细信息

通过田间定位试验,研究少耕轮作和小麦秸秆覆盖方式对小麦间作玉米产量和水分利用效率的影响。结果表明,少耕轮作和留茬覆盖小麦间作玉米具有明显的增产和提高水分利用效率(WUE)的作用。一个轮作周期内,间作轮作中小麦籽粒产量较相应单作轮作提高43.98%～55.55%,玉米籽粒产量较相应单作轮作提高61.03%～69.98%,增产效果显著;间作轮作的耗水量及WUE较相应单作轮作分别增加42.07%～43.94%与11.54%～15.51%。与传统间作相比,少耕轮作留茬覆盖可显著提高产量、水分利用效率和降低间作的耗水量,25cm高等量秸秆覆盖免耕处理较其他间作处理产量与水分利用效率分别提高2.54%～10.97%与4.13%～15.69%,耗水量降低1.54%～4.09%。所以25cm高等量秸秆覆盖免耕处理为本试区减少水分无效损耗、提高WUE的可行模式,是试区内较适宜采取的耕作措施。

关键词：秸秆覆盖作物轮作产量水分利用效率

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米非司酮联合甲氨蝶呤孕囊内注射对内生型剖宫产瘢痕妊娠的临床效果分析

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中国基层医药 2020年第10期27卷 1226-1229页

作者：吴坚吕世文胡发龙金华市妇幼保健院药剂科浙江省321000 金华市中心医院药剂科浙江省321000 金华市妇幼保健院妇产科浙江省321000

目的探讨米非司酮联合甲氨蝶呤孕囊内注射对内生型剖宫产瘢痕妊娠(CSP)的临床效果。方法选择金华市妇幼保健院2014年6月至2019年6月收治的内生型CSP患者106例为研究对象,按照随机数字表法分为对照组53例与观察组53例。对照组行宫腔镜下... 详细信息

目的探讨米非司酮联合甲氨蝶呤孕囊内注射对内生型剖宫产瘢痕妊娠(CSP)的临床效果。方法选择金华市妇幼保健院2014年6月至2019年6月收治的内生型CSP患者106例为研究对象,按照随机数字表法分为对照组53例与观察组53例。对照组行宫腔镜下刮宫术,观察组在对照组基础上结合米非司酮联合甲氨蝶呤孕囊内注射。比较两组治疗疗效、血β-人绒毛膜促性腺激素(β-HCG)恢复正常时间、术中出血量及术后并发症和住院时间。结果观察组治疗总有效率[92.45%(49/53)]高于对照组[75.47%(40/53)],差异有统计学意义(χ^2=5.675,P0.05);观察组住院时间[(7.83±1.52)d]短于对照组[(9.68±2.19)d],差异有统计学意义(t=5.052,P<0.05)。结论米非司酮联合甲氨蝶呤孕囊内注射对内生型CSP患者临床效果良好,可加快血β-HCG恢复正常时间,值得临床借鉴。

关键词：妊娠,异位剖宫产术瘢痕绒毛膜促性腺激素,β亚单位,人手术中并发症住院时间米非司酮甲氨蝶呤

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禾豆间作氮素高效利用机理及农艺调控途径研究进展

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中国生态农业学报 2017年第1期25卷 19-26页

作者：柴强胡发龙陈桂平甘肃省干旱生境作物学重点实验室/甘肃农业大学农学院兰州730070

为保障粮食安全,农业生产中化肥使用极为普遍,但过量使用,往往引起地下水污染、温室效应加剧、生物多样性降低等多种环境和生态问题。禾豆间作系统由于不同作物生物学特性和氮素利用存在差异,进行合理调控可充分发挥生物固氮优点,从而... 详细信息

为保障粮食安全,农业生产中化肥使用极为普遍,但过量使用,往往引起地下水污染、温室效应加剧、生物多样性降低等多种环境和生态问题。禾豆间作系统由于不同作物生物学特性和氮素利用存在差异,进行合理调控可充分发挥生物固氮优点,从而减少化肥投入,提高生产效益,是一种稳产、高产、高效可持续的种植体系。该系统中"氮转移"、"氮阻遏"消减和氮素时空分异是目前研究的热点,也是促进豆科作物固氮、减少化肥投入的有效途径,可实现禾、豆两种作物对氮素的高效利用。特别是该系统中作物品种、施氮制度、空间布局以及种植密度等农艺措施是对种间关系进行调控的必要手段,合理优化可有效促进禾/豆间作竞争与互补协同作用,增强氮素协调利用,从而挖掘两种作物对氮素高效利用的生物学潜力。为此,本文基于前人研究成果和农业可持续发展观点,重点综述了国内外有关禾豆间作氮素高效利用主要机理及相关农艺调控途径的研究现状,旨在为构建简易、高产、高效、氮肥节约型禾豆间作模式提供有力的科学依据和理论支撑。

关键词：禾豆间作氮转移氮阻遏种间关系氮素高效利用

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我国耕作制度研究进展与展望

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寒旱农业科学 2022年第10期1卷 19-25页

作者：柴强胡发龙省部共建干旱生境作物学国家重点实验室甘肃兰州730070 甘肃农业大学农学院甘肃兰州730070

农业生产在满足人民对粮食基本需求和美好生活需要的同时,正面临耕地资源锐减、环境健康受损和土壤退化加剧等历史性挑战,与此相关的耕作制度再一次受到人们关注,并被赋予新的历史使命,给当代农业生产问题的解决从耕作制度视角提供历史... 详细信息

农业生产在满足人民对粮食基本需求和美好生活需要的同时,正面临耕地资源锐减、环境健康受损和土壤退化加剧等历史性挑战,与此相关的耕作制度再一次受到人们关注,并被赋予新的历史使命,给当代农业生产问题的解决从耕作制度视角提供历史经验和参考。从耕作制度演变及内涵变迁、耕作制度研究的作用与贡献以及耕作制度发展的驱动力和现实挑战三个方面进行了详细综述,同时针对耕作制度改革、智能化发展等提出了未来研究重点。

关键词：耕作制度粮食安全农业区划利用效率可持续

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