基于高通量测序的象山港水域细菌多样性的研究

象山港位于浙江省宁波市东南部沿海,属于半封闭式海湾,是以海水养殖区和海洋牧场示范区为主的重要多功能水域,近年来生态环境问题日益突出。为研究象山港海域在早春低水温环境中细菌的多样性,通过高通量测序方法对3月份的象山港水域进行检测。沿象山港南部海湾随机选取6个取样点(G04,G06,G08,G09,G011,G012),共检出836属和2 166种细菌,隶属33个门、91纲、186目和352科。其中优势细菌类群主要包括变形菌门(Proteobacteria)、拟杆菌门(Bacteroidetes)、放线菌门(Actinobacteria)、厚壁菌门(Firmicutes)和蓝细菌门(Cyanobacteria)。变形菌门在G04中占比最高(91.45%),拟杆菌门在G09中占比最高(18.05%);而放线菌门在G12中占比最高(7.95%)。在经度较高且离海岸较远的水域,细菌丰富度也越高;同时随着取样位点纬度的增加,γ-变形菌丰度逐步增高,其中在G04中最高(72.76%),在G12中最低(29.11%)。各取样点的细菌分离培养结果也表明弧菌属丰度较高,且主要集中在G04中。利用高通量测序方法揭示了象山港早春全水域的细菌结构组成框架图,可为象山港的水产养殖和可持续发展提供参考依据。     

3种鲍16S rRNA基因片段序列的初步研究

本文对引自日本的盘鲍 (H aliotisdiscusdiscus)、皱纹盘鲍 (H.discushannai)和大鲍 (H.gi-gantiea) 3个自然群体的线粒体 DNA 1 6S r RNA基因片段进行了扩增和测序 ,分析了 52 8bp的碱基序列 ,结果显示 :3种鲍的基因序列中 A+T含量为 56.74%～ 57.1 2 %。 3个自然群体间碱基片段序列差异不显著 ,盘鲍与皱纹盘鲍、大鲍彼此均仅有 1处核苷酸检测到变异 ,皆为碱基转换 ,同源性为99.81 % ;皱纹盘鲍与大鲍有 2处碱基转换 ,同源性为 99.61 %。 1 6Sr RNA基因在鲍属内表现出很高的保守性。     

基于"一带一路"建设的环渤海地区港口优势评价

港口作为海陆运输的节点,是一个城市和国家的重要门户,对推动经济发展和对外贸易有着不可忽视的作用。基于国家提出的"一带一路"建设,评估环渤海港口的发展优势,逐步实现从沿海、沿江开放向内陆延伸具有重要意义。文章选取环渤海港口中的大连、天津、唐山、丹东、营口、锦州、秦皇岛、黄骅、日照、青岛、威海和烟台共12个港口进行发展优势对比。从港口吞吐量、港口规模范围、港口城市及腹地、港口未来发展4个方面构建环渤海港口优势评价体系。并利用熵权-TOPSIS法进行深入的实证分析。结果表明,环渤海港口群港口发展优势水平悬殊,基本可以分为4个档次。基于此,环渤海各港口应合理准确定位,通过错位发展和协同合作等方式谋求共赢。     

大菱鲆体重和主要体型比率性状的遗传动态分析

The objective of this study was to estimate genetic parameters of body width(BW)to body length(BL)ratio(BW/BL)and of body weight traits(BWT)in turbot,and to elucidate the genetic mechanism of the two traits during ontogeny by dynamic genetic analysis.From 3 to 27 months,BW,BL and BWT of each communally stocked fish were measured every 3 months.The BW/BL ratio was measured at different sampling ages.A twotrait animal model was used for genetic evaluation of traits.The results showed that the heritability values of BW/BL ratio ranged from 0.2168 to 0.3148,corresponding to moderate heritability.The BWT heritability values ranged from 0.2702 to 0.3479 corresponding to moderate heritability.The heritability of BW/BL ratio was lower than that of BWT,except at 3 months of age.Genetic correlation between BW/BL ratio and BWT decreased throughout the measurement period.Genetic correlations were higher than the phenotypic correlations.The current results for estimating genetic parameters demonstrate that the BW/BL ratio could be used as a phenotypic marker of fast-growing turbot,and the BW/BL ratio and BWT could be improved simultaneously through selective breeding.     

Helmert方差分量估计在GPS/GLONASS/BDS组合定位权比确定中的应用

因GNSS系统间观测噪声、轨道精度的差异,采用经验权比进行组合定位难以得到最优结果。基于此,在GPS/GLONASS/BDS组合定位中引入Helmert方差分量估计,对GPS/GLONASS/BDS组合单点定位和基线解算中各系统观测值进行合理定权。实验表明,采用该方法确定的伪距观测值最佳权比为5∶1∶1,相位观测值最佳权比为1∶1∶1,有效提高了GPS/GLONASS/BDS组合定位的精度和可靠性。     

体重和温度对华贵栉孔扇贝(Chlamys nobilis)耗氧率和排氨率的影响

采用室内实验生态学方法对华贵栉孔扇贝的耗氧率和排氨率进行了研究。旨在为华贵栉孔扇贝养殖容量的调查及生态生理的研究提供参考,并可为海洋生态系统动力学和贝类能量学研究提供科学依据。实验结果表明,在实验温度(13—33℃)范围内,华贵栉孔扇贝的耗氧率(OR)和排氨率(NR)与体重(W)都呈负相关,可以用Y=aW-b表示。华贵栉孔扇贝的耗氧率和温度的关系可以表示为OR=-c+b1T-b2T2。在13—28℃温度范围内,华贵栉孔扇贝的耗氧率随温度的升高而增加,28℃时,耗氧率达到最大值,温度升高到33℃时,耗氧率反而下降。而排氨率与温度的关系可以表示为1NR=c1edT,在实验温度范围内,排氨率随温度的升高则呈持续升高趋势。华贵栉孔扇贝呼吸和排泄Q10值范围分别为0.466—2.471和1.129—2.437。在23—28℃温度范围内,不同规格华贵栉孔扇贝的耗氧率和排氨率的比值(原子数O:N)较高。方差分析表明,体重、温度及二者的交互作用对华贵栉孔扇贝的耗氧率和排氨率均有极显著的影响(P0.01)。华贵栉孔扇贝的日常代谢明显高于标准代谢,耗氧率和排氨率平均值分别提高29.9%和69.4%。     

LMWOA (low molecular weight organic acid) exudation by salt marsh plants: Natural variation and response to Cu contamination

This work aimed to evaluate, in vitro, the capability of roots of two salt marsh plants to release low molecular weight organic acids (LMWOAs) and to ascertain whether Cu contamination would stimulate or not organic acids exudation. The sea rush Juncus maritimus and the sea-club rush Scirpus maritimus, both from the lower Douro river estuary (NW Portugal), were used. Plants were collected seasonally, four times a year in 2004, during low tide. After sampling, plant roots were washed for removal of adherent particles and immersed for 2 h in a solution that matched salinity (3) and pH (7.5) of the pore water from the same location to obtain plant exudates. In one of the seasons, similar experiments were carried out but spiking the solution with different amounts of Cu in order to embrace the range between 0 and 1600 nM. In the final solutions as well as in sediment pore water LMWOAs were determined by high performance liquid chromatography. Plants were able to release, in a short period of time, relatively high amounts of LMWOAs (oxalate, citrate, malate, malonate, and succinate). In the sediment pore water oxalate, succinate and acetate were also detected. Therefore, plant roots probably contributed to the presence of some of these organic compounds in pore water. Exudation differed between the plant species and also showed some seasonally variation, particularly for S. maritimus. The release of oxalate by J. maritimus increased with Cu increase in the media. However, exudation of the other LMWOAs did not seem to be stimulated by Cu contamination in the media. This fact is compatible with the existence of alternative internal mechanisms for Cu detoxification, as denoted by the fact that in media contaminated with Cu both plant species accumulated relatively high amounts (29–83%) of the initially dissolved Cu. This study expands our knowledge on the contribution of globally dominant salt marsh plants to the release of LMWOAs into the environment.     

基于交通网络空间权重的区域经济空间相关分析——以甘肃省为例

在区域经济中,交通是联系地理空间和区域经济活动的纽带,交通的发达程度决定了各地理单元空间相互作用的广度与深度.针对不同交通模式赋以不同的权重,基于最短加权交通网络,提出新的空间权重矩阵构建方法,构建了交通网络空间权重,与各种传统空间权重一起,对比研究甘肃省各县域单元之间的区域经济的空间相关性.研究结果表明,利用交通网络空间权重生成的空间权重矩阵,能更真实地反映区域间实际的空间过程;甘肃省的区域经济具有空间相关性但不显著,核心城市经济外溢现象不明显.     

层次分析法在下垫面因子影响沙尘暴危险度研究中的应用

沙尘暴是一种危害严重的气象灾害,其形成依赖于大气环流和沙质地表两种不同密度的物理介质的相互作用,风力条件和下垫面的性质是影响沙尘暴强度和危害程度的两个重要因素。减轻沙尘暴危害的有效方法就是改善沙尘暴源地的下垫面状况,但这需要评估下垫面各因子在不同天气、气候背景条件下对沙尘暴发生的影响程度。从下垫面的角度出发,以内蒙古中西部地区为例,利用气象资料和实测数据,应用AHP方法对下垫面定性与定量因子进行综合分析,得出不同地区下垫面因子对沙尘暴发生作用的权重,为从下垫面角度研究沙尘暴危险度奠定基础。     

特征分析模型构造原理

本文研究在矿产资源评价中适用于不同条件的,特征分析模型的构造原则和方法:建立一般特征分析模型的最大标度准则;变量权和样品关联度的不同算法和解释;基于不同相似性度量标准的矿床模型及建立广义矿化模型的方法;构造多维特征分析模型和进行定量资源评价的可能性。