杭州西溪湿地沉积物细菌的群落结构和多样性

采用Illumina Mi Seq高通量测序技术,对杭州西溪湿地4种不同植被下沉积物的细菌多样性进行了研究。通过提取样品基因组DNA,对16S r RNA V3、V4区测序,共获得有效序列67734条,产生2181个OTU,序列平均长度为441 bp,其中大于400bp的序列占99.74%。对97%相似水平的OTU代表序列进行分类学分析,结果表明,沉积物具有很高的细菌多样性,涵盖了30个门252个属的细菌。其中变形菌门(Proteobacteria)是各样品的优势类群,所占比例高达30.0%—64.7%。同时,β-变形菌纲、γ-变形菌纲和δ-变形菌纲在变形菌门中占主导地位,在这些类群中发现有大量与N、S等元素代谢相关的菌群,应该在湿地沉积物的元素循环中发挥着重要作用。此外,4个样品中约有10%—15%的序列属于无法确定分类位置(Unclassified)的类群,说明西溪湿地沉积物中蕴藏有较多的潜在新物种。本研究结果将为西溪湿地的保护和修复提供理论和实践依据。     

沙冬青根瘤菌结瘤基因nodA PCR-RFLP分析

 利用结瘤基因nodA PCR-RFLP和nodA PCR产物序列分析技术,对36株分离自沙冬青根瘤菌菌株的共同结瘤基因nodA进行了遗传类型和系统发育关系分析。试验结果表明,36株根瘤菌nodA PCR-RFLP分析显示在80%的相似水平上聚为两个类群5个亚群;选取不同基因型代表菌株的nodA进行序列测定和系统发育关系分析表明,测试菌株CCNWNX0117、CCNWNX0068、CCNWNX0083、CCNWNX0062、CCNWNX0058与中慢生根瘤菌聚在一起,系统发育地位相近;测试菌株CCNWNX0089、CCNWNX0081、CCNWNX0064与中华根瘤菌聚在一起,有较高的序列相似性。本研究中nodA基因所揭示的沙冬青根瘤菌遗传多样性和系统发育关系说明沙冬青根瘤菌nodA基因遗传多样性较高,宿主结瘤范围较宽。     

舟山海域好氧不产氧光合异养细菌群落结构分析

好氧不产氧光合异养细菌(aerobic anoxygenic phototrophic bacteria,AAPB)是广泛分布在各种海洋环境中并在微生物生态学、海洋碳汇和海洋生态系统的生物地球化学循环的过程中具有潜在的重要作用的一类光合异养微生物。于2016年4月份在舟山群岛不同海洋功能区海域的八个站点采集表层海水,基于编码光合反应复合中心小亚基的puf M基因进行高通量测序,对测序结果进行分析,结果发现:除了岱山的样品测序失败以外,其它七个站点共得到192633条序列,我们进行了OTU聚类分析,相似性设为97%,可以看到,所有的数据最后一共分成4051个OTU。属于Proteobacteria的AAPB占明确分类的各细菌门的97%。Rhodobacteraceae科的Loktanella和Roseobacter两个属的AAPB在所有的采样站点中都处于优势地位。Desulfocapsa属在朱家尖站位(ZJJ)的发现非常具有研究价值,在以往的研究中还没有出现过。研究结果表明,在舟山群岛不同功能海域AAPB的群落结构和分布情况也是有差别的,而且与很多环境因素有关,这可以解释为什么目前很难准确预测水生环境总AAPB分布的问题。     

凡纳滨对虾(Litopenaeus vannamei)亲虾繁殖期水体微生物多样性

为了揭示凡纳滨对虾(Litopenaeus vannamei)繁殖期亲虾养殖水体的微生物多样性,我们比较了雌雄虾养殖水体细菌群落结构差异,采用Illumina HiSeq高通量测序方法对凡纳滨对虾亲虾养殖水体细菌的16S rRNA基因的两个高变区(V3-V4)进行测序分析,并进行了α-多样性指数和β-多样性指数分析。结果表明:雌雄虾养殖水体细菌群落的α-多样性指数中Chao1,ACE和Goods-coverage指数无显著差异(P0.05),而Observed-species,Shannon和Simpson指数有显著性差异(P0.05)。主坐标分析和聚类热图分析表明雌雄虾养殖水体的细菌群落结构不同,变形菌门(Proteobacteria)和拟杆菌门(Bacteroidetes)为两者共同的优势菌门,但其相对丰度有一定差异,在雄虾养殖池水体中相对丰度分别为76.15%和21.28%;在雌虾养殖池水体中相对丰度分别为66.01%和29.02%。两者的核心微生物群(属水平)明显不同,雄虾养殖水体的核心属主要包括Glaciecola、Octadecabacter、Methylobacterium、Psychroserpens、Olleya;雌虾养殖水体的核心属主要包括Pseudomonas、Polaribacter、Pseudoalteromonas、Vibrio、Arcobacter、Synechococcus、Hyphomonas、Paracoccus、HTCC、Thalassomonas、Thalassobius、Owenweeksia等,其中包括了Vibrio、Pseudomonas和Owenweeksia等病原相关菌类。该实验结果对凡纳滨对虾育苗阶段亲虾的健康管理、病害诊断及防治具有重要意义。     

我国近岸多室草苔虫(Bugula neritina)的群体遗传分化研究

基于线粒体控制区序列和SLAF-seq,对重要药源生物多室草苔虫的群体遗传分化水平开展了研究。控制区序列中检测到8个单倍型,单倍型多样性（h）和核苷酸多样性（π）分别为0.130 7和0.000 7,单倍型网络图和NJ系统进化树的结构都较简单,无明显拓扑结构。中性检验和核苷酸不配对分析结果均表明多室草苔虫未经历过大规模群体扩张。F_st和AMOVA分析显示遗传变异主要来自于群体内。SLAF建库共开发得到214 409个SLAF标签,其中多态性SLAF标签23 437个,共开发出99 432个SNP位点。群体间的遗传距离较小,且低于群体内的遗传距离。基于SNP所做的系统发育树和群体遗传结构分析表明,各群体之间没有显著的遗传结构。综上所述,我国沿海多室草苔虫的遗传多样性水平较低,不同地理群体之间不存在显著的遗传结构。多室草苔虫较强的扩散能力是造成上述结果的主要原因。另外,本研究还验证和讨论了SLAF-seq应用在海洋生物群体遗传分化研究中的可行性和优势。     

Recommendations for developing and applying genetic tools to assess and manage biological invasions in marine ecosystems

The European Union’s Marine Strategy Framework Directive (MSFD) aims to adopt integrated ecosystem management approaches to achieve or maintain “Good Environmental Status” for marine waters, habitats and resources, including mitigation of the negative effects of non-indigenous species (NIS). The Directive further seeks to promote broadly standardized monitoring efforts and assessment of temporal trends in marine ecosystem condition, incorporating metrics describing the distribution and impacts of NIS. Accomplishing these goals will require application of advanced tools for NIS surveillance and risk assessment, particularly given known challenges associated with surveying and monitoring with traditional methods. In the past decade, a host of methods based on nucleic acids (DNA and RNA) analysis have been developed or advanced that promise to dramatically enhance capacity in assessing and managing NIS. However, ensuring that these rapidly evolving approaches remain accessible and responsive to the needs of resource managers remains a challenge. This paper provides recommendations for future development of these genetic tools for assessment and management of NIS in marine systems, within the context of the explicit requirements of the MSFD. Issues considered include technological innovation, methodological standardization, data sharing and collaboration, and the critical importance of shared foundational resources, particularly integrated taxonomic expertise. Though the recommendations offered here are not exhaustive, they provide a basis for future intentional (and international) collaborative development of a genetic toolkit for NIS research, capable of fulfilling the immediate and long term goals of marine ecosystem and resource conservation.     

高等学校毕业生分配的模糊数学方法

本文用模糊数学原理建立了高等学校毕业生分配工作的数学模型,其中各因素的权重排序由层次分析法确立。通过梯形分布建立模糊分布,排除了各方面人为因素的干扰,并用实例说明了这种方法的可行性和可靠性。     

Heuristic approaches for mine planning and production scheduling

Summary Traditional methods and opimization methods for mine planning and production scheduling have failed to provide easy to use tools that yield improved results. Two new approaches, each combining the best of the traditional and the optimization, are described.     

Plant responses to global change: next generation biogeography

Global change has become a major ecological concern that has the potential to dramatically alter plant distributions and assemblages worldwide. The specific response of plants to global change will depend on their ability to move, evolve, or adjust through phenotypic plasticity. Advances in biogeographic research are on the verge of a giant leap forward if we can take advantage of emerging tools in genetics and genomics. In this review, we appraise how new, post-Sanger, high-throughput sequencing and associated technologies can be used by next generation biogeographers to assess plant responses to global change. First, we briefly review the recent advances in genome sequencing and available approaches of genomic analysis. Secondly, we discuss the three main plant responses to global change: migration, adaptation, and phenotypic plasticity. This review is intended to spark the interest of biogeographers who do not traditionally use genetics but could benefit from including genetic and genomic tools into their research. Our goal is to illustrate that their use can contribute to new perspective and add an additional level of resolution into future biogeographic research.     

中华绒螯蟹与日本绒螯蟹线粒体COI基因片段的序列比较研究

以相应引物 PCR扩增了黄河口中华绒螯蟹线粒体细胞色素氧化酶 I亚基基因 (COI)片段 ,PCR产物经 T载体连接之后进行克隆、测序 ,得到 70 9bp的碱基序列 ,其 A,T,G,C含量分别为 34.4 1% ,2 7.93% ,2 0 .0 3%和 17.6 3%。并比较它与珠江流域中华绒螯蟹 COI序列和日本绒螯蟹 COI序列的差异 ,发现黄河口中华绒螯蟹与珠江流域中华绒螯蟹 COI序列完全相同 ,而与日本绒螯蟹差异非常明显 ,70 9或 6 5 8(不计引物 )位点中核苷酸差异数为 32 ,核苷酸差异率为 4 .5 1%或 4 .86 % (不计引物 ) ,其中 2 5个位点为转换 ,7个位点为颠换。作者倾向于支持存在中华绒螯蟹和日本绒螯蟹 ,或它们为同一种的两个地理亚种的观点