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Influences of agricultural phenology dynamic on land surface biophysical process and climate feedback

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Journal of Geographical Sciences 2017年第9期27卷 1085-1099页

作者： liu fengshan CHEN Ying SHI Wenjiao ZHANG Shuai TAO Fulu GE Quansheng Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Re- sources Research CAS Beijing 100101 China Fujian Agriculture and Forestry University Fuzhou 350002 China College of Resources and Environment University of Chinese Academy of Sciences Beijing 100049 China

Response and feedback of land surface research priorities in the field of geoscience. The process to climate change is one of the current study paid more attention to the impacts of global change on land surface process, but the feedback of land surface process to climate change has been poorly understood. It is becoming more and more meaningful under the framework of Earth system science to understand systematically the relationships between agricultural phenology dynamic and biophysical process, as well as the feedback on climate. In this paper, we summarized the research progress in this field, including the fact of agricultural phenology change, parameterization of phenology dynamic in land surface progress model, the influence of agricultural phenology dynamic on biophysical process, as well as its feedback on climate. The results showed that the agriculture phenophase, represented by the key phenological phases such as sowing, flowering and maturity, had shifted significantly due to the impacts of climate change and agronomic management. The digital expressions of land surface dynamic process, as well as the biophysical process and atmospheric process, were improved by coupling phenology dynamic in land surface model. The agricultural phenology dynamic had influenced net radiation, latent heat, sensible heat, albedo, temperature, precipitation, circulation, playing an important role in the surface energy partitioning and climate feedback. Considering the importance of agricultural phenology dynamic in land surface biophysical process and climate feedback, the following research priorities should be stressed：（1） the interactions between climate change and land surface phenology dynamic; （2） the relations between agricultural phenology dynamic and land surface reflectivity at different spectrums; （3） the contributions of crop physiology characteristic changes to land surface biophysical process; （4） the regional differences of climate feedbacks from phenology dynamic in different climate zones. This review i

关键词： agricultural phenology land surface biophysical process land surface process model climate feedback

he adaptive chirplet transform and its application in GPR target detection

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Applied Geophysics 2009年第2期6卷 192-200页

作者： Zeng Zhaofa Wu Fengshou Huang Ling liu fengshan Sun Jiguang Collage of Exploration Science and Technology Jilin University Changchun 130026 China Applied Mathematic Research Center Delaware State University Dover DE 19901 USA

探地雷达不仅能够探测金属目标体,而且能够探测非金属目标体,而成为UX0和地雷探测的一种重要的浅部地球物理方法。但是在地雷和UX0探测中,目标体埋藏深度浅,在探地雷达数据信噪比较低情况下,地表和土壤层的反射严重干扰对目标体的拾取... 详细信息

探地雷达不仅能够探测金属目标体,而且能够探测非金属目标体,而成为UX0和地雷探测的一种重要的浅部地球物理方法。但是在地雷和UX0探测中,目标体埋藏深度浅,在探地雷达数据信噪比较低情况下,地表和土壤层的反射严重干扰对目标体的拾取。本文采用自适用Chirplet变换来消除地表层和土壤层变化的干扰,并在Radon—Wigner分布的基础上,采用自适用Chirplet变换来拾取目标体的信号。通过对实际探测实验数据应用证明,本方法处理结果比传统的偏移方法具有较高的信噪比,并能清晰地提取目标体信号。

关键词：探地雷达小波变换雷达目标探测自适应调频 Wigner分布应用地球物理方法

Status of Stratigraphy Research in China

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Acta Geologica Sinica(English Edition) 2016年第4期90卷 1069-1081页

作者： YAO Jianxin BO Jingfang HOU Hongfei WANG Zejiu MA Xiulan liu fengshan HU Guangxiao JI Zhansheng WU Guichun WU Zhenjie LI Suping GUO Caiqing LI Ya Key Laboratory of Stratigraphy and Paleontology Ministry of Land and Resources Institute of GeologyChinese Academy of Geological Sciences Beijing 100037 China Chinese Academy of Geological Sciences Beijing 100037 China China Geological Survey Beijing 100037 China

Scientific research and productive practice for earth history are inseparable from the accurate stratigraphic framework and time framework. Establishing the globally unified, precise and reliable chronostratigraphic series and geological time series is the major goal of the International Commission on Stratigraphy （ICS）. Under the leadership of the ICS, the countries around the world have carried out research on the Global Standard Stratotype-section and Points （GSSPs） for the boundaries of chronostratigraphic systems. In the current International Chronostratigraphic Chart （ICC）, 65 GSSPs have been erected in the Phanerozoic Eonothem, and one has yet been erected in the Precambrian Eonothem. Based on the progress of research on stratigraphy especially that from its subcommissions, the ICS is constantly revising the ICC, and will publish a new International Stratigraphic Guide in 2020. After continual efforts and broad international cooperation of Chinese stratigraphers, 10 GSSPs within the Phanerozoic Eonothem have been approved and ratified to erect in China by the ICS and IUGS. To establish the standards for strafigraphic division and correlation of China, with the support from the Ministry of Science and Technology, the National Natural Science Foundation of China and the China Geological Survey, Chinese stratigraphers have carried out research on the establishment of Stages in China. A total of 102 stages have been defined in the ＂Regional Chronostratigraphic Chart of China （geologic time）＂, in which 59 stages were studied in depth. In 2014, the ＂Stratigraphic Chart of China＂ was compiled, with the essential contents as follows： the correlation between international chronostratigraphy and regional chronostratigraphy of China （geologic time）, the distributive status of lithostratigraphy, the characteristics of geological ages, the biostratigraphic sequence, the magnetostratigraphy, the geological events and eustatic sea-level change during every geological stage. The ＂Stratigraphical Guide of China and its Exp

关键词： Stratigraphy research process status China.

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芦竹属菌草腋芽萌发期耐盐性评价

福建农林大学学报（自然科学版） 2024年第4期53卷 541-548页

作者：蔡杨星林冬梅曹秀明刘斌林辉罗海凌刘凤山林占熺福建农林大学国家菌草工程技术研究中心福建农林大学菌草与生态学院(碳中和学院) 福建农林大学食品科学学院福建福州350002

【目的】筛选腋芽萌发期耐盐性较强的芦竹属菌草品种,为该类菌草耐盐品种培育提供参考。【方法】以国内外不同地区的12个芦竹属菌草品种为试材,对150 mmol·L^(-1) NaCl溶液处理后腋芽萌发期的各个指标(芽长、根长、芽鲜质量、根鲜质量... 详细信息

【目的】筛选腋芽萌发期耐盐性较强的芦竹属菌草品种,为该类菌草耐盐品种培育提供参考。【方法】以国内外不同地区的12个芦竹属菌草品种为试材,对150 mmol·L^(-1) NaCl溶液处理后腋芽萌发期的各个指标(芽长、根长、芽鲜质量、根鲜质量、发芽势、发芽率、发芽指数和活力指数)进行测定。利用模糊隶属函数法和聚类分析法对供试品种的耐盐性进行综合评价。【结果】与对照组相比,在150 mmol·L^(-1) NaCl胁迫下,所有供试品种的发芽势均降低,芽长、根长、芽鲜质量和根鲜质量都减小;除LZ_NO.1、LZ_NO.3和LZ_NO.7外,其他品种的发芽率均下降;活力指数受盐胁迫的影响最大。基于各指标耐盐系数隶属函数值的临近度对12个品种进行聚类分析,结果表明:LZ_NO.1、LZ_NO.3和LZ_NO.7为一类,属高耐盐型;LZ_NO.2、LZ_NO.4和LZ_NO.6为一类,属盐敏感型。【结论】腋芽萌发期耐盐性较强的芦竹属菌草品种为LZ_NO.1、LZ_NO.3和LZ_NO.7;根据活力指数可判定芦竹属菌草品种的质量优劣。

关键词：芦竹属菌草腋芽萌发耐盐性隶属函数分析法聚类分析

A CLASS OF RANDOM NUMBER GENERATORS BASED ON WEYL SEQUENCE

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Applied Mathematics(A Journal of Chinese Universities) 2005年第4期20卷 483-490页

作者： Liang Heng liu Qinghua Bai fengshan Dept. of Math. Sci. Tsinghua Univ. Beijing 100084China.

The generation of good pseudo-random numbers is the base of many important fields in scientific computing, such as randomized algorithms and numerical solution of stochastic differential equations. In this paper, a class of random number generators （RNGs） based on Weyl sequence is proposed. The uniformity of those RNGs is proved theoretically. Statistical and numerical computations show the efficiency of the methods.

关键词： pseudo-random number randomized algorithm statistical test uniform distribution.

Calculations of narrow-band transimissities and the Planck mean absorption coefficients of real gases using line-by-line and statistical narrow-band models

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Frontiers in Energy 2014年第1期8卷 41-48页

作者： Huaqiang CHU Mingyan GU Huaichun ZHOU fengshan liu School of Energy and Environment Anhui University of TechnologyMa'anshan 243002 China Key Laboratory for Thermal Science and Power Engineering of Ministryof Education Tsinghua University Beijing 100084 China Insti-tute for Chemical Process and Environmental Technology NationalResearch Council Montreal Road Ottawa Ont. K1A 0R6 Canada

狭窄乐队的 transmissivities 在光谱 150 ～ 9300 cm1 并且在 25 cm1 的一致分辨率的范围被计算用统计狭窄乐队(SNB ) 与 Soufiani 和 Taine 的乐队参数当模特儿， Andr

关键词：吸收系数模型参数普朗克气体柱计算窄带统计光谱数据库

Energy partitioning and environmental influence factors in different vegetation types in the GEWEX Asian Monsoon Experiment

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Frontiers of Earth Science 2014年第4期8卷 582-594页

作者： fengshan liu Fulu TAO Shenggong LI Shuai ZHANG Dengpan XIAO Meng WANG Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Graduate University of Chinese Academy of Sciences Beijing 100049 China Institute of Geographical Sciences Hebei Academy of Sciences Shijiazhuang 050011 China

Environmental influences upon energy balance in areas of different vegetation types （i.e., forest at Kog-Ma in Thailand and at Yakutsk in Russia, grassland at Amdo in Chinese Tibet and at Arvaikheer in Mongolia, and mixed farmland at Tak in Thailand） in the GEWEX Asian Monsoon Experiment were investigated. The sites we investigated are geographically and climatologically different; and consequently had quite large variations in temperature （T）, water vapor pressure deficit （VPD）, soil moisture （SM）, and precipitation （PPT）. During May- October, the net radiation flux （Rn）（in W·m^-2） was 406.21 at Tak, 365.57 at Kog-Ma, 390.97 at Amdo, 316.65 at Arvaikheer, and 287.10 at Yakutsk. During the growing period, the Rn partitioned into latent heat flux （2E/Rn） was greater than that partitioned into sensible heat flux （H/Rn） at Tak and at Kog-Ma. In contrast, 2E/Rn was lower than H/Rn at Arvaikheer, H/Rn was less than 2E/Rn between DOY 149 and DOY 270 at Amdo, and between DOY 165 and DOY 235 at Yakutsk. The R, partitioned into ground heat flux was generally less than 0.15. The short-wave albedo was 0.12, 0.18, and 0.20 at the forest, mixed land, and grass sites, respectively. At an hourly scale, energy partitions had no correlation with environmental factors, based on average summer half- hourly values. At a seasonal scale energy partitions were linearly correlated （usually p 〈 0.05） with T, VPD, and SM. The 2E/Rn increased with increases in SM, T, and VPD at forest areas. At mixed farmlands, ）λE/Rn generally had positive correlations with SM, T, and VPD, but was restrained at extremely high values of VPD and T. At grasslands, λE/Rn was enhanced with increases of SM and T, but was decreased with VPD.

关键词： energy balance vegetation type netradiation latent heat flux sensible heat flux short-wavealbedo GEWEX Asian Monsoon Experiment

Spatially Resolved Properties of the GW170817 Host Galaxy

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Research in Astronomy and Astrophysics 2023年第7期23卷 80-95页

作者： Yubin Li Jirong Mao Jianbo Qin Xianzhong Zheng fengshan liu Yinghe Zhao Xiaohong Zhao Yunnan Observatories Chinese Academy of SciencesKunming 650011China Center for Astronomical Mega-Science Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650011China Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China

GW170817 is the unique gravitational-wave(GW)event associated with the electromagnetic(EM)counterpart GRB 170817A.NGC 4993 is identified as the host galaxy of GW170817/GRB 170817A.In this paper,we focus on the spatially resolved properties of NGC 4993.We present the photometric results from the comprehensive data analysis of the high spatial-resolution images in the different optical bands.The morphological analysis reveals that NGC 4993 is a typical early-type galaxy without significant remnants of a major galaxy merger.The spatially resolved stellar population properties of NGC 4993 suggest that the galaxy center has passive evolution with the outskirt formed by gas accretion.We derive the merging rate of the compact object per galaxy by a co-evolution scenario of a supermassive black hole and its host galaxy.If the galaxy formation is at redshift 1.0,the merging rate per galaxy is from 3.2×10^(-4)to 7.7×10^(-5)within the merging decay time from 1.0 to 5.0 Gyr.The results provide vital information for ongoing GW EM counterpart detections.The Hubble space telescope data analysis presented in this paper can be also applied to Chinese Space Station Telescope research in the future.

关键词： galaxies:evolution (stars:)binaries:general gravitational waves

Impact of thermal time shift on wheat phenology and yield under warming climate in the Huang-Huai-Hai Plain, China

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Frontiers of Earth Science 2017年第1期11卷 148-155页

作者： Dengpan XIAO Yongqing QI Zhiqiang LI Rende WANG Juana P. MOIWO fengshan liu Institute of Geographical Sciences Hebei Academy of Sciences Shijiazhuang 050011 China Key Laboratory for Agricultural Water Resources Hebei Key Laboratory for Agricultural Water-Saving Center for Agricultural Resource Research Institute of Genetics and Development Biology Chinese Academy of Sciences Shijiazhnang 050021 China Department of Agricultural Engineering School of Technology Njala University Freetown Sierra Leone Juncao Research Institute Fujian Agriculture and Forestry University Fuzhou 350002 China

Given climate change can potentially influence crop phenology and subsequent yield, an investigation of relevant adaptation measures could increase the understanding and mitigation of these responses in the future. In this study, field observations at 10 stations in the Huang- Huai-Hai Plain of China （HHHP） are used in combination with the Agricultural Production Systems Simulator （APSIM）-Wheat model to determine the effect of thermal time shift on the phenology and potential yield of wheat from 1981-2009. Warming climate speeds up winter wheat development and thereby decreases the duration of the wheat growth period. However, APSIM-Wheat model simulation suggests prolongation of the period from flowering to maturity （Gr） of winter wheat by 0.2-0.8 d·10yr^-1 as the number of days by which maturity advances, which is less than that by which flowering advances. Based on computed thermal time of the two critical growth phases of wheat, total thermal time from floral initiation to flowering （TT_floral_initiation） increasesd in seven out of the 10 investigated stations. Altematively, total thermal time from the start of grainfilling to maturity （TT_start grain_fill） increased in all investigated stations, except Laiyang. It is thus concluded that thermal time shift during the past three decades （1981- 2009） prolongs Gr by 0.2-3.0 d·10yr^-1 in the study area. This suggests that an increase in thermal time （TT） of the wheat growth period is critical for mitigating the effect of growth period reduction due to warming climatic condition. Furthermore, climate change reduces potential yield of winter wheat in 80% of the stations by 2.3-58.8 kg·yr^-1. However, thermal time shift （TTS） increases potential yield of winter wheat in most of the stations by 3.0-51.0 Received September 16, 2015; accepted January 24, 2016 kg·yr^-1. It is concluded that wheat cultivars with longer growth periods and higher thermal requirements could mitigate the negative effects of warming climate on crop production in the study area.

关键词： adaptation thermal time shift crop phenology winter wheat warming climate