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Advances in estimation methods of vegetation water content based on optical remote sensing techniques

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Science china(Technological sciences) 2010年第5期53卷 1159-1167页

作者： ZHANG JiaHua1,XU Yun1,YAO FengMei2,WANG PeiJuan1,GUO WenJuan1,LI Li1 & YANG LiMin3 1 chinese academy of Meteorological sciences,beijing 100081,china 2 Graduated University of chinese academy of sciences,beijing 100049,china 3 USGS/EROS Data Center,South Dakota 57198,USA chinese academy of Meteorological sciences Beijing China Graduated University of chinese academy of sciences Beijing China USGS/EROS Data Center South Dakota USA

Quantitative estimation of vegetation water content(VWC) using optical remote sensing techniques is helpful in forest fire as-sessment,agricultural drought monitoring and crop yield *** paper reviews the research advances of VWC retrieval using spectral reflectance,spectral water index and radiative transfer model(RTM) *** also evaluates the reli-ability of VWC estimation using spectral water index from the observation data and the *** on two main definitions of VWC-the fuel moisture content(FMC) and the equivalent water thickness(EWT),the retrieval accuracies of FMC and EWT using vegetation water indices are ***,the measured information and the dataset are used to estimate VWC,the results show there are significant correlations among three kinds of vegetation water indices(i.e.,WSI,NDⅡ,NDWI1640,WI/NDVI) and canopy FMC of winter wheat(n=45).Finally,the future development directions of VWC detection based on optical remote sensing techniques are also summarized.

关键词： optical remote sensing vegetation water content estimation method water index FMC EWT radiative transfer model

Identification of a protein associated with circulative transmission of Barley yellow dwarf virus from cereal aphids, Schizaphis graminum and Sitobion avenae

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chinese Science Bulletin 2003年第19期48卷 2083-2087页

作者： WANG Xifeng & ZHOU Guanghe State Key Laboratory for Biology of Plant Diseases and Insect Pests, institute of Plant Protection, chinese academy of agricultural sciences, beijing 100094, china State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant Protection Chinese Academy of Agricultural Sciences Beijing China

Using 2-D electrophoresis and virus overlay assay, a 50-kDa protein (P50) exhibiting specific binding to purified virus particles of BYDV-GAV was found in the protein extracts from Schizaphis graminum and Sitobion avenae, two aphid species transmitting BYDV-GAV. P50 in the extracts of S. graminum was isolated by preparation electrophoresis and electro-eluted proteins from the gel slices for antiserum preparation. After feeding the antiserum through membrane, the transmission efficiencies of S. graminum and S. avenae for BYDV-GAV decreased significantly. It was suggested that P50 should be related with transmission pro- cess. Location of P50 was found at the plasma membrane surrounding the accessory salivary gland (ASG) in the head tissues of S. graminum by immunogold-labelling experiment. The ascertainment of the protein associated with virus transmission has a significance influence on further understanding the transmission mechanism and genetic engineering for resistant to vector transmission.

关键词：蛋白质大麦黄矮病麦蚜虫病虫害

Factors governing formation of todorokite at atmospheric pressure

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Science china Earth sciences 2005年第10期48卷 1678-1689页

作者： CUI Haojie1, FENG Xionghan1, LIU Fan1, TAN Wenfeng1 & HE Jizheng2 1. College of Resources and Environment, Huazhong agricultural University, Wuhan 430070, china 2. research Center for Eco-environmental sciences, chinese academy of sciences, beijing 100085, china Huazhong agricultural University chinese academy of sciences

Todorokite commonly occurs in Earth surface environments. The factors governing formation of todorokite, such as reaction temperature, metal ions, dissolved O2 and pH, were investigated in this paper. Results showed that the forming rate of todorokite and its crystallinity decreased with falling reaction temperature, and the effect of temperature was more significant than that of other parameters. Nature of metal ions in the interlayer of buserite precursor and the structure of the buserite precursor obviously affected buserite transformation into todorokite. Weak bonding between the metal ions and MnO6 layer of buserite was favorable to todorokite formation. The rate of todorokite formation was promoted at a lower temperature with appropriate bubbling of O2. The pH in the system slightly influenced the todorokite formation, and todorokite could also be formed in a weak alkali medium or in a slightly acidic medium. Aged buserite pre-cursor more easily form todorokite than the unaged one.

关键词： todorokite, buserite, manganese oxide mineral, atmospheric pressure, transformation.

Exploiting pattern and sustainable development of marginal lands in the Three Gorge Reservoir Areas

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Journal of Environmental sciences 2001年第2期13卷 173-179页

作者： WU Gang, LI Jing, KONG Hong mei, ZHAO Jing zhu, GAO Lin (Department of Ecology System, research Center for Eco Environmental sciences, chinese academy of sciences, beijing 100085, china) Department of Ecology System Research Center for Eco- Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

This paper studied the distribution and utilization status, reasonable exploitation patterns and potential productivity, and sustainable development of marginal lands in the Three Gorge Reservoir Areas. It has been pointed that problems of the soil fertility degradation, poor productivity in crop lands, natural disasters and environmental deterioration existed in all the exploited marginal lands. In order to maintain the sustainability of the marginal lands, following measure have been proposed: prohibiting cultivation in the crop lands with a slope more than 25°, restoring vegetation in the slope more than 25°, strengthening the basic agricultural construction, establishing the production base of woody feeds and oils, establishing a multi dimensional management model with reasonable structure and optimum function for forestry, agriculture and fishing.

关键词： marginal lands utilization pattern sustainable development Three Gorge Reservoir Are4

Progress and prospects of studies on Polymyxa graminis and its transmitted cereal viruses in china

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Progress in Natural Science:Materials International 2005年第6期15卷 481-490页

作者： CHEN Jianping*(Virology and biotechnology institute, Zhejiang academy of agricultural sciences, Key Laboratory of Plant Virology, Ministry of Agriculture and Zhejiang Province, Hangzhou 310021, china) Key Laboratory of Plant Virology Virology and Biotechnology Institute Zhejiang Academy of Agricultural Sciences Hangzhou 310021 China

Polymyxa graminis is a eukaryotic obligate biotrophic parasite of plant roots that belongs to a poorly studied discrete taxonomic unit informally called “plasmodiophorids”. P. graminis is nonpathogenic, but has the ability to acquire and transmit nine plant viruses which belong to genera Bymovirus and Furovirus and cause serious diseases in cereal crop species and also result in significant yield reductions in china and elsewhere. Genus Bymovirus contains barley yellow mosaic virus (BaYMV), barley mild mosaic virus (BaMMV), wheat yellow mosaic virus (WYMV), wheat spindle streak mosaic virus (WSSMV), and oat mosaic virus (OMV), and genus Furovirus contains soil-borne wheat mosaic virus (SBWMV), oat golden stripe virus (OGSV), and newly identified chinese wheat mosaic virus (CWMV) and soil-borne cereal mosaic virus (SBCMV). All these viruses have been sequenced and their worldwide distributions have been studied. The viruses are protected by the environment within P. graminis resting spores that may remain dormant but viable for decades (probably until a suitable host plant is encountered). Spontaneous deletion mutants of SBWMV, OGSV and OMV are detected, and these deletion mutants are not transmissible by the fungus. The persistent, soil-borne nature of these diseases makes the use of virus-resistant crop varieties currently the only practical and environmentally friendly means to control them, and a large number of disease resistant germplasms have been screened.

关键词： Polymyxa graminis cereal viruses genus Bymovirus genus Furovirus.

Function of agricultural Land Use and Its Evolvement in Peri-urban Area: A Case Study of beijing

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chinese Journal of Population,Resources and Environment 2007年第2期5卷 67-71页

作者： Yuan Hong, Cai Jianming, Jiang Fang, Liu Shenghe institute of Geographical sciences and Natural Resources research, chinese academy of sciences, beijing 100101, china institute of Geographical sciences and Natural Resources research Chinese Academy of Sciences Beijing 100101 China

Rapid urbanization in beijing stimulates the urban land expansion and diminishes available agricultural land. Monofunctional agricultural land use can not meet the demand of the devel- opment of the multifunctional agriculture and urbanization any more, so multifunctional agricultural land use is going to be promoted in the city. This article proposes the evolvement of the land use change from 1992 to 2004 and discusses some evolvement views.

关键词： function agricultural land use peri-urban area

Transcritption regulation of soybean ribulose-1,5-bisphos-phate carboxylase small sub-unit gene by external factors

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chinese Science Bulletin 2002年第1期47卷 37-43页

作者： HE Chaoying, WANG Weiquan,DONGFANG Yang, ZHANG Jinsong, GAI Junyi& CHEN ShouyiPlant biotechnology Laboratory, institute of Genetics, chinese academy of sciences, beijing 100101, china National Center for Soybean Improvement, Soybean research Inst Plant biotechnology Laboratory Institute of Genetics Chinese Academy of Sciences Beijing China National Center for Soybean Improvement Soybean Research Institute Nanjing Agricultural University Nanjing China

Ribulose-l,5-bisphosphate carboxylase small subunit gene (rbcS) is present with multi-gene family in plant genome. In Glycine max, the rbcS polypeptide (EC4.***.1.39) is encoded by a gene family containing 4-8 members. Three full-length rbcS cDNA clones were isolated and characterized from soybean seedlings, and both of their nucleotide and amino acid sequences showed high similarity. Differential accumulation of the rbcS mRNA was observed among roots, hypocotyls, cotyledons, epicotyls and leaves. The rbcS genes were up-regulated by various external factors such as salicylic acid (SA), salt stress and drought stress. The expression level of rbcS genes after being treated by 2.0 mmol/L SA and0.4% NaCl, respectively, is 2.5-3.0-fold as high as that of control sample. Moreover, soybean rbcS mRNA was accu-mulated with diurnal variation but easily influenced by light and low temperature.

关键词： soybean ribulose-1 5-bisphosphate carboxylase small subunit gene (rbcS) salicylic acid water stress diurnal variation.

中国特色农业农村现代化的内涵特征与工程化路径

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农业工程学报 2024年第10期40卷 298-305页

作者：农业农村部规划设计研究院课题组张辉农业农村部规划设计研究院北京100125 不详

中国特色农业农村现代化,是中国式现代化的根基。该研究从历史逻辑、理论逻辑和实践逻辑全面分析了中国特色农业农村现代化的演进逻辑,明确了内涵要义,分析了基本特征,探讨了推进路径,并提出相关政策建议。研究表明,加快中国特色农业农... 详细信息

中国特色农业农村现代化,是中国式现代化的根基。该研究从历史逻辑、理论逻辑和实践逻辑全面分析了中国特色农业农村现代化的演进逻辑,明确了内涵要义,分析了基本特征,探讨了推进路径,并提出相关政策建议。研究表明,加快中国特色农业农村现代化,是中国“三农”历史逻辑的必然选择,是党的“三农”理论逻辑的必然结果,是全面建设社会主义现代化国家实践逻辑的必然要求。从内涵特征分析,中国特色的农业农村现代化,既有农业农村现代化普遍具有的农业竞争力强、乡村多功能性强、城乡融合水平强和支持保护力度强等共同特征,也具有鲜明的国情特征、制度特征、任务特征、时代特征、路径特征和本质特征等中国特色。推进中国特色农业农村现代化,要以工程项目为抓手,实施稳产保供固本工程、乡村产业全链工程、和美乡村建设工程、乡村生态循环工程、乡村文化赋能工程、科技创新攻关工程、农民收入提升工程等。研究可为推动“三农”工作及工程化推进提供理论支撑。

关键词：中国特色农业农村现代化演进逻辑内涵特征工程化路径

Studies on the Primers Screening for AFLP Fingerprints of Rice Cultivars

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agricultural sciences in china 2002年第9期1卷 949-953页

作者： ZHANG Chun-qing and JIA Ji-zeng(institute of Crop Germplasm Resources , chinese academy of agricultural sciences , beijing 100081 , P. R . china) institute of Crop Germplasm Resources Chinese Academy of Agricultural Sciences Beijing 100081 P. R. China

AFLP(amplified fragment length polymorphism) is a very powerful fingerprinting technology. The key of making variety fingerprints is to select specific powerful primers for each crop. A quick and effective procedure for selecting AFLP primers for rice variety fingerprinting was established as the following: (1) Choose3 or more group materials that have close genetic relations. (2) Select potential polymorphic primers from primer pairs that are 2 + 2 primer crosses and same at two ends. (3) Recombine the selected potential polymorphic primers and choosing more polymorphic primers. (4) Add one selecting base at one end to become 2 + 3 or 3 + 2 primers and further selecting more polymorphic primers. Some primers were selected with this procedure, such as M21 P87 and M73P17, with which the fingerprints had more polymorphism and high quality.

关键词： Rice AFLP fingerprint Primer selection