华贵栉孔扇贝两种壳色群体生长和消化酶活力比较

以华贵栉孔扇贝桔黄和紫褐壳色个体为亲本建立两个壳色群体,从壳长、壳高、壳宽和体重几方面进行生长比较,并对两个群体做了淀粉酶和纤维素酶活力比较。结果表明:桔黄壳色群体的平均壳长、平均壳高、平均壳宽和平均体重显著大于紫褐壳色群体(P<0.05)。在24℃、27℃、30℃和33℃条件下,桔黄壳色群体的淀粉酶和纤维素酶活力显著高于紫褐壳色群体(P<0.05);不同壳色群体生长与其淀粉酶和纤维素酶活力有关。     

拉格朗日插值法在渔业资源评估上的应用

应用拉格朗日插值法拟合鱼类体长与体重之间的函数关系 ,使用计算机VB语言进行编写程序 ,与常用的线性回归法、Ricker法进行比较 ,得出体长与体重的关系式为Pn(x) =∑nk=0yklk(x)=∑nk=0(∏nj=0j≠kx-xjxk-xj)yk 。     

Analysis of genetic diversity and differentiation of seven stocks of Litopenaeus vannamei using microsatellite markers

Seven microsatellite markers were used to evaluate the genetic diversity and differentiation of seven stocks of Litopenaeus vannamei, which were introduced from Central and South America to China. All seven microsatellite loci were polymorphic, with polymorphism information content(PIC) values ranging from 0.593 to 0.952. Totally 92 alleles were identified, and the number of alleles(Na) and effective alleles(Ne) varied between 4 and 21 and 2.7 and 14.6, respectively. Observed heterozygosity(Ho) values were lower than the expected heterozygosity(He) values(0.526–0.754), which indicated that the seven stocks possessed a rich genetic diversity. Thirty-seven tests were detected for reasonable significant deviation from Hardy-Weinberg equilibrium. Fis values were positive at five loci, suggesting that there was a relatively high degree of inbreeding within stocks. Pairwise Fst values ranged from 0.0225 to 0.151, and most of the stock pairs were moderately differentiated. Genetic distance and cluster analysis using UPGMA revealed a close genetic relationship of L. vannamei between Pop2 and Pop3. AMOVA indicated that the genetic variation among stocks(11.3%) was much lower than that within stocks(88.7%). Although the seven stocks had a certain degree of genetic differentiation and a rich genetic diversity, there is an increasing risk of decreased performance due to inbreeding in subsequent generations.     

金融危机下股市网络的结构特性研究

利用复杂网络的方法,以各国股市为节点,以各股市问的关联性为边,建立起各国股市间的关联网络。通过Matlab编程计算研究了该网络的结构特性,分析出国际股市网络具有典型的小世界性和明显的社区结构,不具有无标度性。进而从网络结构上分析了金融危机的蔓延发生。并通过影响强度分析研究了中国股市在国际股市网络中的位置。     

储良广眼砧穗不亲和问题研究

储良广眼的砧穗不亲和现象在众多个体中呈现从亲和至不亲和的连续变化，随砧、穗周长差异的增大，不亲和症状表现突出。砧、穗周长比值与几个生长量指标存在显著相关。提出以砧／穗比作为衡量不亲和程度指标。靠接加砧结果表明对严重不亲和树出现的症状有较大的缓解。     

尼罗罗非鱼Oreochromis niloticus、奥利亚罗非鱼O.aureus和红罗非鱼O.sp.群体遗传多样性的比较

用9对微卫星引物对尼罗罗非鱼Oreochromis niloticus、奥利亚罗非鱼O.aureus和红罗非鱼O.sp.群体的遗传变异进行了比较研究。在3个群体109个个体中共检测到60个等位基因,3个群体的平均等位基因数分别为4.11、1.33和3.44,平均观测杂合度分别为0.528、0.056和0.491,平均期望杂合度分别为0.644、0.091和0.526,平均多态信息含量分别为0.580、0.077和0.466。杂合子偏离度D值分别为0.148、0.222和0.044,表明3个罗非鱼群体存在不同程度的杂合子缺失。卡方检验表明3个群体的大部分位点偏离Hardy-Weinberg平衡,存在遗传漂变现象。群体间遗传分化显著(遗传分化指数FST在0.329到0.656之间,P<0.01)。尼罗罗非鱼和红罗非鱼群体间的遗传距离最小(0.47)。上述分析表明,尼罗罗非鱼的遗传多样性最高,奥利亚罗非鱼的遗传多样性最低,群体间分化显著。表明尼罗罗非鱼和红罗非鱼尚具有一定的选育潜力,而奥利亚罗非鱼遗传多样性低,不利于选择育种,需要引进新的种群。     

中国铝物质流历史变化分析和再生铝资源利用研究

本文采用物质流分析(Material Flow Analysis, MFA)的方法, 构建了铝全生命周期动态物质流分析框架, 自上而下的追踪了1949—2021年中国铝的流量、存量和供需情况。结果表明: 1)1949—2021年中国铝土矿铝物质累计流入量5.86亿t, 国内开采与进口各占一半左右。实际铝物质累计消费量3.74亿t。生命周期内铝损失严重, 铝物质损失量2.39亿t。2)2021年人均铝物质社会存量208.9 kg/人, 与同经济发展时期的北美、日本基本一致。3)1990年以来中国再生铝产量快速增长, 累计0.77亿t, 以国内生产为主, 占比76.7%。随着含铝产品到达寿命及未来铝需求量的持续走高, 将迎来含铝产品的报废时代。建议从全生命周期的角度出发, 减少铝在各个环节的损失量; 合理布局再生铝产业, 提高再生铝的利用, 优化铝供应结构, 促进铝工业低碳转型, 支撑“双碳”目标的实现。     

莱州湾沉积有机碳储量及海洋健康评估

海洋沉积碳储量在全球碳循环中发挥着重要作用,而海湾作为海洋的重要组成部分,近几十年来由于受人类活动影响有机碳循环发生了明显变化,对碳储备能力的响应同样不可忽视,但却鲜有报道。研究区域位于莱州湾(37°~38°N,118.9°~120.3°E),是渤海三大海湾之一。利用39个表层沉积物和其6根沉积箱式柱状样(站位为6154、6174、6184、6194、7211和7214,柱长在17~39cm之间)对海湾有机碳储量进行评估。同时,通过计算海洋健康指数(OHI)十个目标之一的碳储(carbon storage)来评估海洋健康状况。结果表明,莱州湾表层沉积物1cm的有机碳储量平均为0.3t/ha,在研究区域的中部、东部和北部偏高,莱州湾东南部、区域西北部以及黄河口处有机碳储量偏低。莱州湾0~20cm有机碳储量为20.6t/ha,低于我国表层土壤0~20cm有机碳储量29.7t/ha以及浙江、云南、海南和重庆等省市。莱州湾碳储(carbon storage)得分为37,远低于中国平均值51以及世界平均水平75。

     

Potential of High-Resolution Satellite Data in the Context of Vulnerability of Buildings

High-resolution space-borne remote sensing data are investigated for their potential to extract relevant parameters for a vulnerability analysis of buildings in European countries. For an evaluation of large earthquake scenarios, the number of parameters in models for vulnerability is reduced to a minimum of relevant information such as the type of building (age, material, number of storeys) and the geological and spatial context. Building-related parameters can be derived from remote sensing data either directly (e.g. height) or indirectly based on the recognition of the urban structure type in which the buildings are located. With the potential of a fully- or semi-automatic inventory of the buildings and their parameters, high-resolution satellite data and techniques for their processing are a useful supporting tool for the assessment of vulnerability.     

饱和膨润土及其与砂混合物的压缩变形特性

对用不同制样方法得到的饱和膨润土及其与砂混合物进行了压缩试验。试验结果表明,饱和膨润土的压缩曲线呈双线性,不同于普通黏土的压缩曲线。压缩试验中量测了侧向应力,由此得到的饱和膨润土的静止侧向压力系数值较一般黏土的数值要大。对膨润土与砂混合物的击实样进行了由非饱和到饱和状态的浸水试验,并得出试验过程中侧向应力的变化规律。由于浸水饱和的试样和抽真空饱和的试样在较高压力时压缩曲线趋于一致,可采用快速抽真空饱和的方法进行试验研究,以缩短非饱和混合物击实样浸水饱和所需时间。引入骨架孔隙比的概念,用来判断膨润土与砂混合物中砂骨架是否形成,得出影响混合物压缩特性的决定因素。