922 resultados para Borlaug, Norman E. (Norman Ernest), 1914-2009


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<正>2010年1月9~10日,近空间飞行器的关键基础科学问题重大研究计划2009年度学术交流会在北京市昌平区召开.参加会议的有该重大研究计划学术指导专家组、秘书组和管理工作组的成员,项目负责人和部分项目组成员,共计150余人.

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This article documents the addition of 512 microsatellite marker loci and nine pairs of Single Nucleotide Polymorphism (SNP) sequencing primers to the Molecular Ecology Resources Database. Loci were developed for the following species: Alcippe morrisonia morrisonia, Bashania fangiana, Bashania fargesii, Chaetodon vagabundus, Colletes floralis, Coluber constrictor flaviventris, Coptotermes gestroi, Crotophaga major, Cyprinella lutrensis, Danaus plexippus, Fagus grandifolia, Falco tinnunculus, Fletcherimyia fletcheri, Hydrilla verticillata, Laterallus jamaicensis coturniculus, Leavenworthia alabamica, Marmosops incanus, Miichthys miiuy, Nasua nasua, Noturus exilis, Odontesthes bonariensis, Quadrula fragosa, Pinctada maxima, Pseudaletia separata, Pseudoperonospora cubensis, Podocarpus elatus, Portunus trituberculatus, Rhagoletis cerasi, Rhinella schneideri, Sarracenia alata, Skeletonema marinoi, Sminthurus viridis, Syngnathus abaster, Uroteuthis (Photololigo) chinensis, Verticillium dahliae, Wasmannia auropunctata, and Zygochlamys patagonica. These loci were cross-tested on the following species: Chaetodon baronessa, Falco columbarius, Falco eleonorae, Falco naumanni, Falco peregrinus, Falco subbuteo, Didelphis aurita, Gracilinanus microtarsus, Marmosops paulensis, Monodelphis Americana, Odontesthes hatcheri, Podocarpus grayi, Podocarpus lawrencei, Podocarpus smithii, Portunus pelagicus, Syngnathus acus, Syngnathus typhle,Uroteuthis (Photololigo) edulis, Uroteuthis (Photololigo) duvauceli and Verticillium albo-atrum. This article also documents the addition of nine sequencing primer pairs and sixteen allele specific primers or probes for Oncorhynchus mykiss and Oncorhynchus tshawytscha; these primers and assays were cross-tested in both species.

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P>In the Yellow Sea of China, large-scale green tides have broken out for three consecutive years from 2007 to 2009. As part of the efforts to localize the algal source, two cruises were conducted in the early stage and the outbreak stage of the bloom in 2009. We analyzed the morphological and genetic diversity of drifting Ulva specimens and culture-derived isolates from seawater sampled in different localities. For phylogenetic analyses, the nuclear encoded ribosomal DNA internal transcribed spacer region (ITS nrDNA) and the plastid encoded large subunit of ribulose-1, 5-bisphosphate carboxylase/oxgenase gene (rbcL) were used. Our molecular and morphological data indicate that the dominant free-floating Ulva species in 2008 and 2009 possibly belonged to a single strain of the U. linza-procera-prolifera (LPP) clade. The ITS sequences from bloom-forming algal samples with dense branches were identical to those from U. linza-like specimens without branches derived from the Yellow Sea. Microscopic individuals of the dominant Ulva strain were detected in eight stations, revealing that spore dispersal in the water helped to enlarge biomass in the water during the outbreak stage of green tide in the Yellow Sea.

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海洋沉积环境中多氯联苯(PCBs)和多环芳烃(PAHs)的研究对于揭示其污染历史、来源途径、迁移转化以及评价其对环境的潜在生态风险都有重要的科学意义和应用价值,本研究选择我国典型近海中比较开阔的南黄海和受人为影响严重的渤海湾沉积物中的PAHs和PCBs作为主要研究对象,结合对生态环境对应关系的剖析,系统研究了沉积物中PAHs和PCBs的地球化学分布特征、影响控制因素、演变趋势、潜在生态风险等,获得了以下系统的认识: 1.南黄海表层沉积物中多环芳烃和多氯联苯的分布与沉积类型及模式相一致,受控于“沉积类型-动力过程-来源途径”。PCBs含量(范围:518~5848 pg/g,平均值:1715 pg/g)低于受人为影响严重的长江口、珠江口和渤海,分布具有中部海区>东部海区>西部海区的特征;PCBs随着沉积物粒径的减小和粘土含量的增加而增加,且与总有机碳(r=0.61,p<0.01)含量呈显著线性正相关,表明PCBs在沉积物中的分布受控于被水动力过程原动力控制的沉积类型与沉积模式。 2. 1914~2004年间,南黄海沉积物中PAHs和PCBs的变化比较显著,在时间序列上经历了三个明显的不同阶段。近90年来,PAHs和PCBs在柱状样中垂直分布随深度的增加而降低,即近年南黄海沉积物中PAHs和PCBs的残留水平比上世纪初明显增加。其中1914~1932年间,PAHs和PCBs保持在较低的水平;1932~1962年间,PAHs和PCBs的含量发生急剧的变化,在1932~1944和1956~1962年两个时间段,PAHs和PCBs的含量达到峰值;自1962年至今,PAHs和PCBs呈稍有增加趋势。PAHs的组成和特征组分比值分析显示,1920~1944年间PAHs主要来自石油产品泄漏,1944~1980年间,主要来自草/木材/煤燃烧,1980年至2004年则显示出石油和燃烧产物混合来源的特征。 3.渤海湾沉积物中的PAHs、PCBs、DDTs和HCHs的分布模式不同,反映了这四种污染物的地球化学行为存在着明显的差异性。PAHs、PCBs、DDTs和HCHs的含量范围为149.0~393.4 ng/g,360.8~1728.3 pg/g,462.2~2007.3 pg/g和4.31~33.8 ng/g。马颊河口、海河口和黄河口附近的海区的沉积物中PAHs和PCBs的含量显著高于渤海湾内其它站位,DDTs在湾外沉积物中的含量大于湾内,在海河口附近站位测得HCHs含量的最高值,在其它站位其浓度变化不大。PAHs特征成分的比值显示渤海湾沉积物中PAHs主要来源于草/木材/煤燃烧的产物经过大气的输运过程进入水体;DDTs和HCHs的组成显示,在DDTs和HCHs被禁用后仍有新的输入源。 4.南黄海沉积物POPs总体水平不高,其环境污染危害和潜在生态风险不大,从沉积物POPs的角度来说南黄海的环境质量较好。潜在生态危害指数评价表明,渤海湾沉积物中芴可能会产生潜在的生态风险,DDTs和HCHs的含量低于一类沉积物质量标准值,总体而言,其沉积物质量良好,潜在生态风险较低。 论文的创新性点在于:1)首次研究了近百年南黄海沉积物中多环芳烃和多氯联苯的演变趋势,判断了其来源并对近百年二者的潜在生态风险进行评价。2)系统剖析了南黄海及渤海湾的生态环境与PAHs和PCBs的耦合关系,对阐明POPs的毒理效应有重要的科学意义。3)系统解析了渤海湾沉积物中PAHs,DDTs和HCHs的污染现状,来源和迁移途径,可为科学开发和利用渤海海域提供重要的理论依据。

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