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Integrating phosphorus management and cropping technology for sustainable maize production

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Journal of Integrative Agriculture 2024年第4期23卷 1369-1380页

作者： haiqing gong Yue Xiang Jiechen Wu Laichao Luo Xiaohui Chen Xiaoqiang Jiao Chen Chen State Key Laboratory of Nutrient Use and Management College of Resources and Environmental SciencesCollege of Resources and Environmental SciencesChina Agricultural UniversityBeijing 100193China Department of Sustainable Development Environmental Science and Engineering(SEED)KTH Royal Institute of TechnologyStockholm SE-10044Sweden Anhui Province Key Lab of Farmland Ecological Conservation and Pollution Prevention School of Resources and EnvironmentAnhui Agricultural UniversityHefei 230036China Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering National Observations and Research Station for Wetland Ecosystems of the Yangtze EstuaryInstitute of Biodiversity Science and Institute of Eco-ChongmingCollege of Life SciencesFudan UniversityShanghai 200438China

Achieving high maize yields and efficient phosphorus(P)use with limited environmental impacts is one of the greatest challenges in sustainable maize *** plant density is considered an effective approach for achieving high maize ***,the low mobility of P in soils and the scarcity of natural P resources have hindered the development of methods that can simultaneously optimize P use and mitigate the P-related environmental footprint at high plant *** this study,meta-analysis and substance flow analysis were conducted to evaluate the effects of different types of mineral P fertilizer on maize yield at varying plant densities and assess the flow of P from rock phosphate mining to P fertilizer use for maize production in China.A significantly higher yield was obtained at higher plant densities than at lower plant *** application of single superphosphate,triple super-phosphate,and calcium magnesium phosphate at high plant densities resulted in higher yields and a smaller environmental footprint than the application of diammonium phosphate and monoammonium *** scenario analyses suggest that combining the optimal P type and application rate with a high plant density could increase maize yield by 22%.Further,the P resource use efficiency throughout the P supply chain increased by 39%,whereas the P-related environmental footprint decreased by 33%.Thus,simultaneously optimizing the P type and application rate at high plant densities achieved multiple objectives during maize production,indicating that combining P management with cropping techniques is a practical approach to sustainable maize *** findings offer strategic,synergistic options for achieving sustainable agricultural development.

关键词： maize plant density mineral phosphorus fertilizer meta-analysis substance flow analysis

Satellite-based RAR performance simulation for measuring directional ocean wave spectrum based on SAR inversion spectrum

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Acta Oceanologica Sinica 2010年第4期29卷 13-20页

作者： REN Lin MAO Zhihua HUANG haiqing gong Fang Department of Electromagnetic Fields and Microwave Theory Nanjing University of Science and Technology Nanjing 210094 China State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of Oceanography State Oceanic Administration Hangzhou 310012 China

Some missions have been carried out to measure wave directional spectrum by synthetic aperture radar （SAR） and airborne real aperture radar （RAR） at a low *** them have their own advantages and *** hope that SAR and satellite-based RAR can complement each other for the research on wave properties in the *** this study,the authors aim to simulate the satellite-based RAR system to validate performance for measuring the directional wave *** principal measurements are introduced and the simulation methods based on the one developed by Hauser are adopted and slightly *** enhance the authenticity of input spectrum and the wave spectrum measuring consistency for SAR and satellite-based RAR,the wave height spectrum inversed from Envisat ASAR data by cross spectrum technology is used as the input spectrum of the simulation *** the process of simulation,the sea surface,backscattering signal,modulation spectrum and the estimated wave height spectrum are simulated in each look *** wave spectrum are measured based on the simulated observations from 0 ？ to 360 ？ .From the estimated wave spectrum,it has an 180 ？ ambiguity like SAR,but it has no special high wave number cut off in all the ***,the estimated spectrum is compared with the input one in terms of the dominant wave wavelength,direction and SWH and the results are *** simulation shows that satellite-based RAR should be capable of measuring the directional wave ***,it indicates satellite-based RAR basically can measure waves that SAR can measure.

关键词： satellite-based RAR directional wave spectrum SAR inversion performance simulation

AGRICULTURAL GREEN DEVELOPMENT TO ACHIEVE FOOD SECURITY AND CARBON REDUCTION IN THE CONTEXT OF CHINA'S DUAL CARBON GOALS

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Frontiers of Agricultural Science and Engineering 2023年第2期10卷 262-267页

作者： Yulong YIN Kai HE Zhong CHEN Yangyang LI Fengling REN Zihan WANG Yingcheng WANG haiqing gong Qichao ZHU Jianbo SHEN Xuejun LIU Zhenling CUI College of Resources and Environmental Sciences National Academy of Agriculture Green DevelopmentKey Laboratory of Plant-Soil Interactions(Ministry of Education)Key Laboratory of Low-carbon Green Agriculture(Ministry of Agriculture and Rural Affairs)China Agricultural UniversityBeijing 100193China

The agricultural sector,a major source of greenhouse gas emissions,and emissions from agriculture must be reduced substantially to achieve carbon(C)*** on a literature analysis and other research results,this study investigated the effects and prospects of C reduction in agricultural systems under different scenarios(i.e.,methods and approaches)in the context of China's dual C goals,as those working in the agricultural sector have yet to reach a consensus on how to move *** views,standards,and countermeasures were analyzed to provide a reference for agricultural action supporting China's C neutrality goal.

关键词： agriculture carbon neutrality carbon peak food security carbon mitigation strategies

Establishment of a hyperspectral evaluation model of ocean color satellite-measured reflectance

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Science China(Information Sciences) 2010年第9期53卷 1891-1902页

作者： MAO ZhiHua*,CHEN JianYu,HUANG haiqing,HE XianQiang & gong Fang State Key Laboratory of Satellite Ocean Environment Dynamics,Second Institute of Oceanography,State Oceanic Administration,Hangzhou 310012,China State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of Oceanography State Oceanic Administration Hangzhou China

The accuracy of the satellite-measured reflectance is a key question for data processing and oceanographic applications.A hyperspectral satellite remote sensing reflectance evaluation model(HRSREM) was developed to evaluate the accuracy of the satellite measured *** model can compute the total reflectance at the top of the atmosphere(TOA) according to observation conditions of satellites,based on a radiative transfer model with the consideration of multiple scattering effects and atmospheric absorption *** performance of the HRSREM model was examined by Gordon’s algorithms,showing that the relative errors of the Rayleigh scattering reflectance and the aerosol scattering reflectance are less than 2%.The model can also compute the sky reflectance which can be validated by in-situ *** two sky reflectances match well with a spectral average error of 5.4%.The relative error of the total reflectance of the model,verified by sea-viewing wide field-of-view sensor(SeaWiFS) data,is about 3.5%.Therefore,the total reflectances at TOA,computed by the model,can be taken as reference values to evaluate the accuracy of satellite *** model was used to evaluate the accuracy of the hypersptral satellite(Hyperion) remote sensing *** Hyperion reflectance matches the total reflectance of HRSREM very well at visible and near-infrared bands with an average error of 7.3%,while the status of calibration coefficients at shortwave infrared bands are not stable with a large spectral average error of 63.5%.The reflectance evaluation of a moderate resolution imaging spectrometer(CMODIS) data indicated that relative errors are large,especially at near-infrared bands with relative errors more than 100%.The calibration coefficients of CMODIS,obtained from laboratory measurements,are not *** CMODIS data should be recalibrated for oceanographic *** performance of the HRSREM model is effective in evaluating satellite data and its

关键词： hyperspectral remote sensing CMODIS reflectance evaluation satellite ocean color

不同供氮形态下水稻苗期磷吸收累积与根系形态的关系

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中国水稻科学 2019年第2期33卷 167-175页

作者：陈晨龚海青金梦灿郜红建安徽农业大学资源与环境学院/农田生态保育与污染防控安徽省重点实验室合肥230036

【目的】植物根系形态对于适应低磷胁迫具有一定的可塑性,对提高磷的吸收利用具有重要意义。因此,本研究以长江中下游地区主推的102个水稻品种为供试材料,研究根系形态与水稻幼苗磷吸收利用的相关性。【方法】采用国际水稻所营养液培养... 详细信息

【目的】植物根系形态对于适应低磷胁迫具有一定的可塑性,对提高磷的吸收利用具有重要意义。因此,本研究以长江中下游地区主推的102个水稻品种为供试材料,研究根系形态与水稻幼苗磷吸收利用的相关性。【方法】采用国际水稻所营养液培养方法,研究在NH_4^+-N和NO_3^--N供应条件下苗期植株生物量、磷含量和磷素累积量及其与根系形态指标的相关性。【结果】研究结果表明,在相同供氮水平(40 mg/L)下,供应NH_4^+-N时,水稻苗期平均生物量为67.87 mg/株,比供应NO_3^--N时高4.27 mg/株;水稻苗期平均磷含量为0.49%,比供应NO_3^--N时高0.10%;水稻苗期平均磷累积量为0.37 mg/株,比供应NO_3^--N时高0.10 mg/株。在NH_4^+-N条件下,水稻根系形态指标变异系数呈现根尖数>总根长>分支数>总根面积>交叉数>总根体积>平均根系直径的规律;在NO_3^--N条件下,水稻根系形态指标变异系数呈现根尖数>分枝数>总根长>总根面积>交叉数>总根体积>平均根系直径的趋势。在NH_4^+-N条件下,总根长、总根面积、分枝数、交叉数四个形态指标与植株生物量、磷含量、磷累积相关最为显著(P<0.01),而在NO_3^--N培养下,总根长、总根面积、根尖数、交叉数与植株生物量及磷素吸收累积指标相关性最为显著(P<0.01)。【结论】供应氨态氮,水稻营养指标与根系形态指标的相关性更高。水稻苗期根系总根长、总根面积、交叉数可作为水稻磷高效评价的重要指标。

关键词：水稻氮素形态根系形态磷吸收累积

NH_4^+-N和NO_3^--N供应条件下水稻磷高效品种初选

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中国农业大学学报 2018年第9期23卷 32-42页

作者：陈晨龚海青金梦灿郜红建安徽农业大学资源与环境学院/农田生态保育与污染防控安徽省重点实验室合肥230036

为探讨在NH_4^+-N和NO_3^--N条件下不同水稻品种生物量、磷素含量及磷素累积量的差异。利用国际水稻所营养液培养方法,在相同浓度(40mg/L)NH_4^+-N和NO_3^--N条件下测定102个水稻品种苗期生物量和磷素吸收积累量的差异,并采用隶属函数... 详细信息

为探讨在NH_4^+-N和NO_3^--N条件下不同水稻品种生物量、磷素含量及磷素累积量的差异。利用国际水稻所营养液培养方法,在相同浓度(40mg/L)NH_4^+-N和NO_3^--N条件下测定102个水稻品种苗期生物量和磷素吸收积累量的差异,并采用隶属函数法将评价指标进行标准化,基于磷效率综合值和分层聚类热图分析,进行水稻品种磷效率类型划分。在NH_4^+-N和NO_3^--N下,不同水稻品种的生物量和磷累积量差异性显著,变异系数分别在52.83%~69.54%和52.82%~73.82%。在NH_4^+-N和NO_3^--N培养下的主成分情况相同,主成分1由茎叶生物量、根系生物量、整株生物量、茎叶磷累积量、根系磷累积量和整株磷累积量决定,主要反映植株的生物量及磷素累积量;主成分2由不同器官的磷含量决定。综合水稻苗期磷素吸收累积统计分析方法,将茎叶生物量、根系生物量、整株生物量、茎叶磷累积量、根系磷累积量和整株磷累积量作为水稻苗期磷高效综合评价指标。初步认为‘2845’、‘中籼2503’、‘华瑞稻’、‘连粳7号’、‘德香4103’、‘甬优9号’、‘Ⅱ优602’、‘两优766’、‘盐粳11号’、‘丰两优80’和‘深两优1813’为2种氮素供应下的磷高效型品种/系。

关键词：水稻 NH4^+-N NO3^--N 磷效率磷高效品种

基于动力总成和车身整体的发动机怠速激励下车身振动仿真研究

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现代制造工程 2016年第2期 29-35,51页

作者：袁爽杨啟梁胡溧龚海清武汉科技大学汽车与交通工程学院武汉430081

综合运用多体动力学、有限元法、动态响应灵敏度分析和结构优化方法,研究基于动力总成和车身整体的发动机怠速激励下车身振动的动态仿真。以某国产客车为研究对象,分别建立十二自由度整车动力学模型和白车身有限元模型。以悬置系统的动... 详细信息

综合运用多体动力学、有限元法、动态响应灵敏度分析和结构优化方法,研究基于动力总成和车身整体的发动机怠速激励下车身振动的动态仿真。以某国产客车为研究对象,分别建立十二自由度整车动力学模型和白车身有限元模型。以悬置系统的动载荷为桥梁,将动力学仿真和有限元仿真结合起来,定量求解发动机怠速激励下车身特征点的动态响应。对比分析特征点动态响应的仿真结果与实车测试结果,验证仿真方法的正确性。将此振动仿真方法应用到结构优化中,针对实车上出现怠速工况下VIP座椅位置振动异常问题,以动态响应灵敏度分析为指导,通过对车架和车身底板骨架整体结构局部调整和尺寸优化,提高了客车的乘坐舒适性能。

关键词：多体动力学有限元法动态响应动态响应灵敏度分析结构优化

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发动机激励下客车车身怠速振动仿真研究

武汉科技大学学报 2015年第1期38卷 35-40页

作者：袁爽杨啟梁胡溧龚海清武汉科技大学汽车与交通工程学院湖北武汉430081

以某国产客车为研究对象,综合运用多体动力学和有限元分析法来研究发动机激励下车身的动态响应。在多体动力学软件MotionView中建立整车的动力学模型,在有限元软件HyperMesh中建立车身有限元模型,用MotionSolve求解发动机激励引起的动... 详细信息

以某国产客车为研究对象,综合运用多体动力学和有限元分析法来研究发动机激励下车身的动态响应。在多体动力学软件MotionView中建立整车的动力学模型,在有限元软件HyperMesh中建立车身有限元模型,用MotionSolve求解发动机激励引起的动力总成悬置系统的动载荷,将悬置系统的三向动载荷施加到有限元模型上,用RADIOSS定量求解出车身特征点的动态响应。以发动机怠速工况为例,将车身特征点振动加速度均方根值的仿真计算结果与实车测试结果进行对比分析,验证仿真方法的正确性。结果表明,将多体动力学仿真和有限元仿真有机结合起来研究发动机怠速激励下客车车身的动态响应是行之有效的。

关键词：客车发动机激励动态响应车身振动多体动力学有限元法

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一种双横臂独立悬架动力学模型验证的新方法

汽车技术 2015年第2期 20-23页

作者：龚海清杨啟梁胡溧袁爽武汉科技大学

利用某轻型客车的CATIA三维设计数模进行运动仿真,得到悬架线刚度,并与试验结果进行对比,验证了运动仿真结果的正确性。在ADAMS/Car中建立了双横臂扭杆弹簧独立悬架动力学模型,进行动力学仿真计算得到悬架的线刚度,并通过与CATIA中运动... 详细信息

利用某轻型客车的CATIA三维设计数模进行运动仿真,得到悬架线刚度,并与试验结果进行对比,验证了运动仿真结果的正确性。在ADAMS/Car中建立了双横臂扭杆弹簧独立悬架动力学模型,进行动力学仿真计算得到悬架的线刚度,并通过与CATIA中运动仿真计算所得的线刚度对比分析,验证了动力学模型的正确性。该方法同样适用于其它类型独立悬架的动力学模型验证。

关键词：动力学模型双横臂独立悬架悬架线刚度 ADAMS CATIA