Research on the Database Technology under the Operation of the IOT Huge Amounts of Data

In this paper, we conduct research on the database technology under the basic operation of the IOT huge amounts of data. Spatial data service is the process of basic customer application system service request, directory service system according to the request is mapped into physical addresses, according to the data block physical disk server address block of data read from the disk in parallel and sent to the client the process of application system. In addition, spatial data distribution system should possess unloading, transfer, replication, and optimization of spatial data, and other functions, to achieve comprehensive management and maintenance of spatial data. Under this basis, we propose the enhanced database technology that optimizes the operation with better performance.

珠江河口区大型底栖动物群落结构

河口区大型底栖动物具有的重要群落特征往往可以反映群落所经历的环境污染。为更好地了解珠江河口区大型底栖动物群落结构,作者于2014年11月至2015年8月进行了4个季度的大型底栖动物调查,并利用PRIMER 6.0软件进行群落生物多样性指数计算、群落等级聚类(Cluster)和非度量多维标度排序(nMDS)分析。研究结果显示:珠江河口区共获得大型底栖动物52种,优势种包括光滑河篮蛤(Potamocorbulalaevis)、中国绿螂(Glaucomya chinensis)、焦河篮蛤(Potamocorbulaustulata)和羽须鳃沙蚕(Dendronerispinnaticirrus)。大型底栖动物年平均密度为269.3 ind./m^2,年平均生物量为129.61g/m^2。12个站次的丰富度指数(D)、均匀度指数(J’)和Shannon-Wiener多样性指数(H’)平均值分别为1.81±1.38、0.50±0.27和1.60±1.13。该结果显示除P01断面的秋季和冬季环境质量为优良外,其他站位在不同季度都显示出轻度到重度的污染。Cluster聚类分析和n MDS标序结果表明, P01断面与P02和P03断面群落相似度较低,与断面地理分布情况一致;P02断面和P03断面存在交叉聚集,群落相似度较高。结合环境因子结果可知,沉积物理化因子与群落分布特征相关性较大,其中最能解释珠江河口区群落多样性分布特征的环境因子为盐度和pH值。