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Adaptation of potato production to climate change by optimizing sowing date in the Loess Plateau of central Gansu, China

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Journal of Integrative Agriculture 2015年第2期14卷 398-409页

作者： WANG Chun-ling shen shuang-he ZHANG Shu-yu LI Qiao-zhen YAO Yu-bi School of Applied Meteorology Nanjing University of Information Science and Technology Key Laboratory of Arid Climate Change and Reducing Disaster of Gansu Province Lanzhou Institute of Arid Meteorology China Meteorological Administration Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disaster Meteorological Bureau of Dingxi City

Potato grows in most part of China, it achieves higher yield and better quality in Gansu Province than in others. With global warming, its growth duration has been prolonged and sowing date become earlier than before. Therefore, to regulate its sowing date and growing period is of great significance for better harvest. In this study, experiments were conducted with six sowing-date treatments of potato in Dingxi, which is in the Loess Plateau of central Gansu Province in Northwest China in 2010. The growth period, morphological index and change in yield and their relationships with temperature, precipitation, and other climatic factors were investigated for each treatment. Results show that the crop with different sowing dates experienced different climate conditions, leading to distinct growth duration, plant height, and leaf area index. The growth duration was shortened due to a delay in sowing date. For each 15-day delay in sowing, the growth duration was reduced by 12 days on average. A significant linear relationship was found between numbers of days either from seeding to emergence or from flowering to harvest and mean temperature over the corresponding period. Dry matter accumulation, tuber fresh weight, and final yield were all decreased because of insufficient cumulative temperature over the shorter growing periods. Marked differences in tuber yield were discovered among the six treatments of sowing date, the potato planted on May 27 giving the highest yield. The potato planted either earlier or later would produce invariably lower yield than the treatment of May 27. Late May therefore can be taken as the optimum sowing time of potato in this region because the crop can fully utilize thermal resource. We conclude that to postpone sowing time is a good practice for potato production to adapt to climate warming in the Loess Plateau of central Gansu, China.

关键词： potato climate change optimum sowing date growth and development tuber yield

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Estimating daily actual evapotranspiration of a rice–wheat rotation system in typical farmland in the Huai River Basin using a two-step model and two one-step models

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Journal of Integrative Agriculture 2021年第1期20卷 274-288页

作者： LI Meng CHU Rong-hao Abu Reza Md.Towfiqul ISLAM JIANG Yue-lin shen shuang-he School of Resources and Environment Anhui Agricultural UniversityHefei 230036P.R.China hefei Scientific Observing and Experimental Station of Agro-Environment Ministry of Agriculture and Rural AffairsP.R.China Anhui Public Meteorological Service Center Anhui Meteorological BureauHefei 230031P.R.China Department of Disaster Management Begum Rokeya UniversityRangpur 5400Bangladesh Key Laboratory of Meteorological Disaster Ministry of Education(KLME)ZJoint International Research Laboratory of Climate and Environment Change(ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CICFEMD)/Jiangsu Key Laboratory of Agricultural MeteorologyCollege of Applied MeteorologyNanjing University of Information Science&TechnologyNanjing 210044P.R.China

The objective of this study is to evaluate the performance of three models for estimating daily evapotranspiration(ET) by employing flux observation data from three years(2007, 2008 and 2009) during the growing seasons of winter wheat and rice crops cultivated in a farmland ecosystem(Shouxian County) located in the Huai River Basin(HRB), China. The first model is a two-step model(PM-Kc);the other two are one-step models(e.g., Rana-Katerji(R-K) and advection-aridity(AA)). The results showed that the energy closure degrees of eddy covariance(EC) data during winter wheat and rice-growing seasons were reasonable in the HRB, with values ranging from 0.84 to 0.91 and R2 of approximately 0.80. Daily ET of winter wheat showed a slow decreasing trend followed by a rapid increase, while that of rice presented a decreasing trend after an increase. After calibrating the crop coefficient(Kc), the PM–Kc model performed better than the model using the Kc recommended by the Food and Agricultural Organization(FAO). The calibrated key parameters of the R-K model and AA model showed better universality. After calibration, the simulation performance of the PM-Kc model was satisfactory. Both the R-K model and AA model underestimated the daily ET of winter wheat and rice. Compared with that of the R-K model, the simulation result of the AA model was better, especially in the simulation of daily ET of rice. Overall, this research highlighted the consistency of the PM-Kc model to estimate the water demand for rice and wheat crops in the HRB and in similar climatic regions in the world.

关键词： daily evapotranspiration crop coefficient crop water demand rice–wheat rotation system Huai River Basin

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Rational Solutions of First Order Algebraic Ordinary Differential Equations

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Journal of Systems Science & Complexity 2024年第2期37卷 567-580页

作者： FENG shuang shen Liyong School of Physical and Mathematical Sciences Nanjing Tech UniversityNanjing 211816China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China

Let f(t,y,y')=∑ _(i=0)^(n )a_(i)(t,y)y'^(i)=0 be an irreducible first order ordinary differential equation with polynomial *** in 1998 proved that there exists a constant C such that every rational solution of f(t,y,y')=0 is of degree not greater than *** show that this degree bound C depends not only on the degrees of f in t,y,y' but also on the coefficients of f viewed as the polynomial in t,y,y'.In this paper,the authors show that if f satisfies deg(f,y)0,then the degree bound C only depends on the degrees of f in t,y,y',and furthermore we present an explicit expression for C in terms of the degrees of f in t,y,y'.

关键词： Degree bound first order AODE height rational solution

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Quantifying the impact of earthquakes and geological factors on spatial heterogeneity of debris-flow prone areas:A case study in the hengduan Mountains

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Journal of Mountain Science 2024年第5期21卷 1522-1533页

作者： HU Xudong shen Yitong HU Kaiheng XU Wennian LIU Daxiang he Songtang GAO Jiazhen WEI Li LIU shuang Hubei Provincial Engineering Research Center of Slope Habitat Construction Technique Using Cement-based Materials(China Three Gorges University) Yichang 443002China Hubei Key Laboratory of Disaster Prevention and Mitigation(China Three Gorges University) Yichang 443002China College of Civil Engineering and Architecture China Three Gorges UniversityYichang 443002China Shanghai Investigation Design&Research Institute Co.Ltd.Shanghai 200335China Key Laboratory of Mountain Hazards and Earth Surface Processes Chinese Academy of SciencesChengdu 610041China Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China Wuhan Polytechnic Wuhan 430074China

Understanding the spatial heterogeneity of debris-flow-prone areas holds significant implications for regional risk management, particularly in seismically active regions with geological faults. Despite the significance of this knowledge, a comprehensive quantification of the influence of regional topographical and geological factors on the spatial heterogeneity of debris-flow-prone areas has been lacking. This study selected the hengduan Mountains, an earthquake-prone region characterized by diverse surface conditions and complex landforms, as a representative study area. An improved units zoning and objective factors identification methodology was employed in earthquake and fault analysis to assess the impact of seismic activity and geological factors on spatial heterogeneity of debrisflow prone areas. Results showed that the application of GIS technology with hydrodynamic intensity and geographical units analysis can effectively analyze debris-flow prone areas. Meanwhile, earthquake and fault zones obviously increase the density of debrisflow prone catchments and make them unevenly distributed. The number of debris-flow prone areas shows a nonlinear variation with the gradual increase of geomorphic factor value. Specifically, the area with 1000 m-2500 m elevation difference, 25°-30° average slope, and 0.13-0.15 land use index is the most favorable conditions for debris-flow occurrence;The average annual rainfall from 600 to 1150 mm and landslides gradient from 16° to 35° are the main causal factors to trigger debris flow. Our study sheds light on the quantification of spatial heterogeneity in debris flow-prone areas in earthquake-prone regions, which can offer crucial support for post-debris flow risk management strategies.

关键词： debris-flow prone areas causal factors GIS-based method spatial heterogeneity hengduan Mountains

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Study of primordial deuterium abundance in Big Bang nucleosynthesis

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Nuclear Science and Techniques 2024年第3期35卷 208-215页

作者： Zhi-Lin shen Jian-Jun he Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China

Big Bang nucleosynthesis(BBN)theory predicts the primordial abundances of the light elements^(2) H(referred to as deuterium,or D for short),^(3)he,^(4)he,and^(7) Li produced in the early *** these,deuterium,the first nuclide produced by BBN,is a key primordial material for subsequent *** date,the uncertainty in predicted deuterium abundance(D/H)remains larger than the observational *** this study,the Monte Carlo simulation code PRIMAT was used to investigate the sensitivity of 11 important BBN reactions to deuterium *** found that the reaction rate uncertainties of the four reactions d(d,n)^(3)he,d(d,p)t,d(p,γ)^(3)he,and p(n,γ)d had the largest influence on the calculated D/H ***,the calculated D/H uncertainty cannot reach observational precision even with the recent LUNA precise d(p,γ)^(3) he *** the nuclear physics aspect,there is still room to largely reduce the reaction-rate uncertainties;hence,further measurements of the important reactions involved in BBN are still necessary.A photodisintegration experiment will be conducted at the Shanghai Laser Electron Gamma Source Facility to precisely study the deuterium production reaction of p(n,γ)d.

关键词： Big Bang nucleosynthesis Abundance of deuterium Reaction cross section Reaction rate Monte Carlo method

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物候模型研究进展

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生态学杂志 2008年第1期27卷 89-95页

作者：韩小梅申双和南京信息工程大学应用气象学院南京210044

近年来随着全球气候变暖,物候提前,物候学的研究越来越受到人们的关注。通过建立物候模型使物候期的预知成为可能,从而为生产实践活动提供依据和指导。本文探讨了物候模型研究的意义,总结了影响植物和昆虫物候的温度、水分、光和养分等... 详细信息

近年来随着全球气候变暖,物候提前,物候学的研究越来越受到人们的关注。通过建立物候模型使物候期的预知成为可能,从而为生产实践活动提供依据和指导。本文探讨了物候模型研究的意义,总结了影响植物和昆虫物候的温度、水分、光和养分等主要环境因子的作用。根据国内外物候模型的研究现状,重点介绍了作物、树木、植被和昆虫4类物候模型的研究内容和进展。作物物候模型注重生理生态过程;树木物候模型以统计方法为主,但近期也有尝试将激素水平作为物候的决定因素;植被物候模型以遥感技术的应用为发展趋势;昆虫物候模型则进一步对发育起点的确定和对温度因子的修正,GIS的引入将昆虫物候模型的应用范围扩大。最后指出了目前物候模型研究中存在的问题。

关键词：物候模型作物树木植被昆虫

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Minimizing interfacial energy losses in inverted perovskite solar cells by a dipolar stereochemical 2D perovskite interface

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Journal of Energy Chemistry 2024年第3期90卷 496-503,I0011页

作者： Junjie Qian Jingjing he Qihang Zhang Chenyue Zhu Shilin Chen Zhanpeng Wei Xuesong Leng Ziren Zhou Benben shen Yu Peng Qiang Niu shuang Yang Yu Hou Key Laboratory for Ultrafine Materials of Ministry of Education Shanghai Engineering Research Center of Hierarchical NanomaterialsSchool of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China National Enterprise Technology Center Inner Mongolia Erdos Electric Power and Metallurgy Group Company LimitedOrdos 016064Inner MongoliaChina

Inverted perovskite solar cells(PSCs) have attracted broad research and industrial interest owing to their suppressed hysteresis,cost-effectiveness,and ***,the issue of non-radiative recombination losses at the n-type interface between the perovskite and fullerene has impeded further improvement of photovoltaic ***,we modify the n-type interface of FAPbI_(3) perovskite films by constructing a stereochemical two-dimensional(2D) perovskite interlayer,in which the organic cations comprise both pyridine and ammonium *** pyridine N donor can create stable bonding with the surface-uncoordinated Pb on the perovskite,thereby passivating the shallow-level defects and enhancing the air stability of the ***,the pyridine N donor also offers a positive polar interface to decrease the surface work function of the perovskite film,enabling n-type ***,we employ a p-i-n photovoltaic(PV) device with the positive dipole interlayer at perovskite/fullerene contact and achieve remarkable photoelectric conversion efficiency(PCE) of 22.0%.

关键词： Perovskite solar cells Dipole interlayer Stereochemistry Non-radiative recombination

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作物生长模型的应用研究进展

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中国农业气象 2019年第7期40卷 444-459页

作者：孙扬越申双和南京信息工程大学应用气象学院南京210044 南京信息工程大学气象灾害预警预报与评估协同创新中心南京210044

作物生长模型不仅能够进行单点尺度上作物生长发育的动态模拟,而且能够从系统角度评价作物生长状态与环境要素的关系。本文通过梳理当前作物生长模型应用的诸多研究成果,剖析模型在气候变化对农业生产影响研究、作物生长模型区域应用中... 详细信息

作物生长模型不仅能够进行单点尺度上作物生长发育的动态模拟,而且能够从系统角度评价作物生长状态与环境要素的关系。本文通过梳理当前作物生长模型应用的诸多研究成果,剖析模型在气候变化对农业生产影响研究、作物生长模型区域应用中的关键问题,总结了当前以作物生长模型为核心的农业决策支持系统开发的研究情况,意在促进作物生长模型在生态、农业、区域气候资源和气候变化等研究中更广泛地应用。结果表明,作物生长模型在国内外的研究与应用广泛而深入,在气候变化背景下,应用作物生长模型进行历史时期气候条件和农业气象灾害对作物生产状况和产量的影响研究已相当广泛且相对成熟。利用全球气候模式(GCM)或区域气候模式(RCM)构建未来气候变化情景,再与作物生长模型耦合已发展成为评估未来气候变化对农业生产影响的重要手段。通过集成与整合多作物生长模型、多气候模式集合模拟、优化气候模拟数据订正方法可有效降低气候变化对农业生产影响评估的不确定性。遥感数据同化技术能够将站点模型运用到区域尺度上评价不同环境因子对农业生产的影响,拓宽了作物生长模型的应用尺度范围并有效提高作物产量估算的精度。以作物生长模型为核心的农业决策支持系统的研究与应用越来越多元化,是辅助农业生产管理和决策的重要工具。然而,由于作物生态系统的复杂性,作物生长模型模拟结果仍存在很大的不确定性,今后对作物生长机理及过程间耦合机制的探索还需加强,以便进一步完善和改进模型,促进作物生长模型更广泛地应用。

关键词：作物生长模型作物模型气候变化遥感研究进展

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“Blocking and rebalance” mechanism-guided design strategies of bimetallic doped 2D a-phosphorus carbide as efficient catalysts for N2 electroreduction

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Journal of Energy Chemistry 2024年第10期97卷 68-78页

作者： Cheng he Jianglong Ma shen Xi Wenxue Zhang State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and Engineering Xi'an Jiaotong University School of Materials Science and Engineering Chang'an University

Compared to single atom catalysts（SACs）,the introduction of dual atom catalysts（DACs） has a significantly positive effect on improving the efficiency in the electrocatalytic nitrogen reduction reaction（NRR） which provides an environmental alternative to the Haber-Bosch ***,the research on the mechanism and strategy of designing bimetallic combinations for better performance is still in its early ***,based on "blocking and rebalance" mechanism,45 combinations of bimetallic pair doped α-phosphorus carbide（TMATMB@PC） are investigated as efficient NRR catalysts through density functional theory and machine learning *** a multi-step screening,the combinations of TiV,TiFe,MnMo,and FeW exhibit highly efficient catalytic performance with significantly lower limiting potentials（-0.17,-0.18,-0.14,and-0.30 V,respectively）.Excitingly,the limiting potential for CrMo and CrW combinations is 0 V,which are considered to be extremely suitable for the NRR *** mechanism of "blocking and rebalance" is revealed by the exploration of charge transfer for phosphorus atoms in electron blocking ***,the descriptor φ is proposed with machine learning,which provides design strategies and accurate prediction for finding efficient *** work not only offers promising catalysts TMATMB@PC for NRR process but also provides design strategies by presenting the descriptor φ.

关键词： 2D α-phosphorus carbide DACs Inherent attributes Machine learning Nitrogen reduction reaction

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A Certified Cubic B-Spline Interpolation Method with Tangential Direction Constraints

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Journal of Systems Science & Complexity 2024年第3期37卷 1271-1294页

作者： he Shitao shen Liyong WU Qin YUAN Chunming School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China KLMM Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China

Curve interpolation with B-spline is widely used in various areas. This problem is classic and recently raised in application scenario with new requirements such as path planning following the tangential vector field under certified error in CNC machining. This paper proposes an algorithm framework to solve Hausdorff distance certified cubic B-spline interpolation problem with or without tangential direction constraints. The algorithm has two stages: The first stage is to find the initial cubic B-spine fitting curve which satisfies the Hausdorff distance constraint;the second stage is to set up and solve the optimization models with certain constraints. Especially, the sufficient conditions of the global Hausdorff distance control for any error bound are discussed, which can be expressed as a series of linear and quadratic constraints. A simple numerical algorithm to compute the Hausdorff distance between a polyline and its B-spline interpolation curve is proposed to reduce our *** results are presented to show the advantages of the proposed algorithms.

关键词： Cubic B-spline Hausdorff distance interpolation tangential direction

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