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Contribution of Drought to Potential Crop Yield Reduction in a Wheat-Maize Rotation Region in the North China Plain

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Journal of Integrative Agriculture 2014年第7期13卷 1509-1519页

作者： HU Ya-nan LIU ying-jie TANG Hua-jun xu yin-long PAN Jie Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural Sciences Key Laboratory of Agri-Informatics Ministry of Agriculture/Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences Public Meteorological Service Center Chinese Meteorological Administration

With consecutive occurrences of drought disasters in China in recent years, it is important to estimate their potential impacts on regional crop production. In this study, we detect the impacts of drought on wheat and maize yield and their changes at a 0.5＆#176;＆#215;0.5＆#176; grid scale in the wheat-maize rotation planting area in the North China Plain under the A1B climate change scenario using the Decision Support System for Agrotechnology Transfer （DSSAT） model and the outputs of the regional climate modeling system-Providing Regional Climates for Impacts Studies （PRECIS）. Self-calibrating palmer drought severity index was used as drought recognition indicator. Two time slices used for the study were the baseline （1961-1990） and 40 years of 2011-2050. The results indicate that the potential planting region for double crop system of wheat-maize would expend northward. The statistic conclusions of crop simulations varied considerably between wheat and maize. In disaster-affected seasons, wheat yield would increase in the future compared with baseline yields, whereas in opposite for maize yield. Potential crop yield reductions caused by drought would be lower for wheat and higher for maize, with a similar trend found for the ratio of potential crop yield reductions for both crops. It appears that the negative impact of drought on maize was larger than that on wheat under climate change A1B scenario.

关键词： drought yield DSSAT A1B scenario climate change

Regional Climate Change and Uncertainty Analysis based on Four Regional Climate Model Simulations over China

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Atmospheric and Oceanic Science Letters 2015年第3期8卷 147-152页

作者： WU Jia GAO xue-Jie xu yin-long PAN Jie National Climate Center China Meteorological Administration Climate Change Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural Sciences

Four sets of climate change simulations at grid spacing of 50 km were conducted over East Asia with two regional climate models driven at the lateral bounda- ries by two global models for the period 1981-2050. The locus of the study was on the ensemble projection of cli- mate change in the mid-21st century （2031-50） over China. Validation of each simulation and the ensemble average showed good performances of the models overall, as well as advantages of the ensemble in reproducing present day （1981 2000） December-February （DJF）, June-August （JJA）, and annual （ANN） mean temperature and precipitation. Significant wanning was projected for the mid-21st century, with larger values of temperature increase found in the northern part of China and in the cold seasons. The ensemble average changes of precipitation in DJF, JJA, and ANN were determined, and the uncertainties of the projected changes analyzed based on the consistencies of the simulations. It was concluded that the largest uncertainties in precipitation projection are in eastern China during the summer season （monsoon pre-cipitation）.

关键词： climate change regional climate model ensemble China

Correlation Analysis of Rice Seed Setting Rate and Weight of 1 000-Grain and Agro-Meteorology over the Middle and Lower Reaches of the Yangtze River,China

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Agricultural Sciences in China 2007年第4期6卷 430-436页

作者： ZHAO Hai-yan YAO Feng-mei ZHANG Yong xu Bin YUAN Jing HU Ya-nan xu yin-long Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural Sciences Beijing 100081 P.R China Graduate University Chinese Academy of Sciences Beijing 100039 P.R.China Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 P.R. China

The purpose of this study is to reveal the effects of historic climate change on rice yield over the middle and lower reaches of the Yangtze River, China, and to better adapt to climate change in the future. This study presents the relation of temperature and precipitation and rice components from 1981 to 2003 at 48 early rice stations and 30 middle rice stations. It focuses on an analysis of three stages： flowering, pre-milk, and late milk. The results show that mean maximum temperature and mean daily precipitation at the stages of flowering and pre-milk are most related to early rice yield. Yield change of middle rice is mainly because of mean precipitation change at the flowering stage. Furthermore, percentage of undeveloped grain increases as mean maximum temperature rises at the flowering stage. Over-precipitation in the reproductive stage is a major reason for reduction in yield of early rice. Consecutive rainfall and continuous high temperature can have negative effects on middle rice yield. Global warming would affect middle rice more seriously than early rice.

关键词： mean maximum temperature mean daily precipitation percentage of undeveloped grain percentage of partially developed grain weight of 1 000-grain

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无线网络中高效的匿名漫游安全协议

电子与信息学报 2010年第8期32卷 1961-1967页

作者：金海旻许胤龙王石中国科学技术大学计算机科学与技术学院安徽省高性能计算重点实验室合肥230026 香港城市大学计算机科学系

无线漫游安全(Secure Wireless Roaming,SWR)协议允许隶属于本地服务器的用户漫游到外地时,可以与外地服务器互相验证身份并建立安全的会话密钥。在此基础上,匿名SWR协议能保证即使所有外地服务器串通情况下漫游用户的匿名性和不可追踪... 详细信息

无线漫游安全(Secure Wireless Roaming,SWR)协议允许隶属于本地服务器的用户漫游到外地时,可以与外地服务器互相验证身份并建立安全的会话密钥。在此基础上,匿名SWR协议能保证即使所有外地服务器串通情况下漫游用户的匿名性和不可追踪性。该文提出了一个匿名的无线漫游安全协议SYM-SWR(SYMmetric key based SWR)。而且就目前所知,该协议是第1个完全基于对称密钥的匿名SWR。同其他已知协议相比,SYM-SW的通信复杂度和计算复杂度均最低。因为SYM-SWR只需要4次消息传送,且不需要PKI(Public Key Infrastructure)而采用消息验证码(Message Authentication Code,MAC)和对称密钥加密这两种高效的运算。

关键词：无线漫游安全可认证密钥交换匿名性不可追踪性可证明安全性

PRECIS水平分辨率对宁夏气候模拟影响的试验

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高原气象 2009年第2期28卷 440-445页

作者：徐宾许吟隆中国农业科学院农业环境与可持续发展研究所农业部农业环境与气候变化重点开放实验室北京100081 中国气象局国家气象信息中心气象资料室北京100081

利用1979-1993年ECMWF再分析数据驱动区域气候模式系统PRECIS,分析设置水平网格距为50 km和25 km时对PRECIS模拟宁夏气候效果的影响。模拟结果表明:PRECIS在两种分辨率下能较好地模拟宁夏地区的逐月平均温度和降水的时间序列分布特征,... 详细信息

利用1979-1993年ECMWF再分析数据驱动区域气候模式系统PRECIS,分析设置水平网格距为50 km和25 km时对PRECIS模拟宁夏气候效果的影响。模拟结果表明:PRECIS在两种分辨率下能较好地模拟宁夏地区的逐月平均温度和降水的时间序列分布特征,以及逐日温度和逐日降水发生频率的分布特征。当PRECIS分辨率为25 km时,PRECIS对宁夏地区月平均气温、降水的模拟和日气温与日降水发生频率分布特征的模拟与实况更加吻合,而且对0℃附近温度和极端降水与极端气温模拟的效果明显改善。

关键词：水平分辨率 PRECIS ECMWF 再分析数据

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中国21世纪气候变化的情景模拟分析

南京气象学院学报 2005年第3期28卷 323-329页

作者：许吟隆中国农业科学院农业气象研究所北京100081

利用HadCM2和ECHAM4气候模式比较分析了温室气体排放综合效果相当于CO2浓度逐年递增1%情景下中国区域21世纪地面气温和降水量的变化趋势.结果表明:在温室气体渐进递增情景下,至21世纪末期,相对于1961-1990年的气候基准值,全国地面平均... 详细信息

利用HadCM2和ECHAM4气候模式比较分析了温室气体排放综合效果相当于CO2浓度逐年递增1%情景下中国区域21世纪地面气温和降水量的变化趋势.结果表明:在温室气体渐进递增情景下,至21世纪末期,相对于1961-1990年的气候基准值,全国地面平均气温增幅可达5～6℃.与地面气温的变化相比,降水量的波动幅度较大,但全国范围内降水量变化的总趋势也是增加的.中国区域地面气温和降水量变化的地理分布显示:降水量的增加主要集中在南方区域,HadCM2预测21世纪末期降水增加可达0.9 mm/d,ECHAM4预测可达0.6 mm/d;ECHAM4模式模拟的气温增幅比HadCM2高,尤其是在冬季及中国北方和青藏高原地区,而HadCM2模式模拟的降水量的增加较大,但两个气候模式模拟的地面气温和降水量变化的总趋势大体一致.

关键词：气候模式温室气体排放情景全球变暖

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分布存储VOD系统的负载均衡设计及其仿真

计算机仿真 2009年第4期26卷 186-189,316页

作者：胡涛许胤龙中国科学技术大学计算机科学技术系安徽合肥230027

为了满足日益增长的VOD用户数量,设计了一种多服务器组成的分布式VOD系统,系统中服务器的负载均衡问题成为亟待解决的问题。为了解决负载均衡问题,从用户行为分析入手,建立了用户行为的数学模型,根据用户的节目选择分布以及点播时长分布... 详细信息

为了满足日益增长的VOD用户数量,设计了一种多服务器组成的分布式VOD系统,系统中服务器的负载均衡问题成为亟待解决的问题。为了解决负载均衡问题,从用户行为分析入手,建立了用户行为的数学模型,根据用户的节目选择分布以及点播时长分布,制定了媒体文件按时间分块并分布存储在多服务器上的策略,并根据热度信息的变化,每隔一段时间对各服务器上存储的内容进行重发布,以此达到各服务器的负载均衡。实现了仿真系统,并设计出用户行为仿真程序进行用户点播行为仿真。仿真实验结果显示,使用该重发布策略后,各服务器达到很好的负载均衡,说明策略是有效的。

关键词：视频点播用户行为负载均衡仿真

Investigating Müller glia reprogramming in mice: a retrospective of the last decade, and a look to the future

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Neural Regeneration Research 2025年第4期20卷 946-959页

作者： Zhiyuan yin Jiahui Kang xuan Cheng Hui Gao Shujia Huo Haiwei xu Key Lab of Visual Damage and Regeneration&Restoration of Chongqing Southwest Eye HospitalSouthwest HospitalThird Military Medical University(Army Medical University)ChongqingChina

Müller glia,as prominent glial cells within the retina,plays a significant role in maintaining retinal homeostasis in both healthy and diseased *** lower vertebrates like zebrafish,these cells assume responsibility for spontaneous retinal regeneration,wherein endogenous Müller glia undergo proliferation,transform into Müller glia-derived progenitor cells,and subsequently regenerate the entire retina with restored ***,Müller glia in the mouse and human retina exhibit limited neural reprogramming.Müller glia reprogramming is thus a promising strategy for treating neurodegenerative ocular disorders.Müller glia reprogramming in mice has been accomplished with remarkable success,through various *** in molecular,genetic,epigenetic,morphological,and physiological evaluations have made it easier to document and investigate the Müller glia programming process in ***,there remain issues that hinder improving reprogramming efficiency and ***,understanding the reprogramming mechanism is crucial toward exploring factors that will improve Müller glia reprogramming efficiency,and for developing novel Müller glia reprogramming *** review describes recent progress in relatively successful Müller glia reprogramming *** also provides a basis for developing new Müller glia reprogramming strategies in mice,including epigenetic remodeling,metabolic modulation,immune regulation,chemical small-molecules regulation,extracellular matrix remodeling,and cell-cell fusion,to achieve Müller glia reprogramming in mice.

关键词： cell fusion chemical small-molecules epigenetic extracellular matrix immune metabolic mice Müller glia neurodegenerative diseases reprogramming retina regeneration

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气候变化对非洲水资源和农业的影响

中国农业气象 2016年第3期37卷 259-269页

作者：杨笛熊伟许吟隆中国农业科学院农业环境与可持续发展研究所北京100081

尽管非洲是世界上温室气体排放总量或人均排放量最少的地区,但在承受气候变化造成的恶劣影响方面首当其冲。气候变化已经给非洲的水资源、农业、生物多样性、人类健康和国家安全等带来诸多严重影响,粮食生产和水资源一直是非洲长期面临... 详细信息

尽管非洲是世界上温室气体排放总量或人均排放量最少的地区,但在承受气候变化造成的恶劣影响方面首当其冲。气候变化已经给非洲的水资源、农业、生物多样性、人类健康和国家安全等带来诸多严重影响,粮食生产和水资源一直是非洲长期面临的两大难题,也是深受气候变化影响的两大领域。本文系统梳理了气候变化对非洲水资源系统和农业生产影响的研究成果和不足,以期为非洲气候变化影响评估工作提供一定参考和借鉴。已有的观测结果表明,气候变化导致非洲许多山脉冰川面积正在大范围缩减、大部分地区降水量有所减少,降雨的年际间分布也更为不稳定,通过水文模型的模拟预测,未来气候变化将进一步影响降水量和非洲部分地区河流的径流量,导致非洲水资源供给压力加大。同样,气候变化也给非洲农业生产带来了巨大的挑战,无论是观测结果分析,还是统计模型和作物模型等对不同气候情景和时间尺度下非洲农业的模拟研究,都显示气候变化对非洲农业以负面影响为主,导致非洲干旱加剧、生长季改变和粮食产量下降,并可能危及非洲的粮食安全。然而,现有研究结果还存在较多不确定性,其主要集中在未来气候情景数据、研究方法、数据的质量和数量等方面。与世界其它地区相比,非洲气候变化影响研究无论是研究的深度和广度都还较欠缺,需要在未来的研究中进一步加强,以探寻减缓气候变化对非洲水资源和农业不利影响的有效途径。

关键词：非洲农业气候变化影响评估水资源适应