Spatial and seasonal variations in bacterial communities of the Yellow Sea by T-RFLP analysis

Four typical coastal sites (rocky shore, sandy shore, mud flat shore, and artificial harbor) at the Yellow Sea were chosen to investigate the spatial and seasonal variations in bacterial communities. This was accomplished by using terminal restriction fragment length polymorphism (T-RFLP) analysis of PCR amplified 16S rDNA fragments. Two kinds of tetrameric restriction enzymes, HhaI and MspI, were used in the experiment to depict the bacterial community diversity in different marine environments. It was found that the community compositions digested by the two enzymes separately were different. However, the results of bacterial community diversity derived from them were similar. The MDA analysis results of T-RFLP profiles coming from HhaI and MspI both exhibited a significant seasonal community shift for bacteria and a relatively low spatial variation among the four locations. With HhaI as the sample, the pair wise T-tests also revealed that variations were minor between each pair of marine environments, with R ranging from 0.198 to 0.349. However, the bacterial community structure in the mud flat site depicted a larger difference than each of the other three sites (R ranging from 0.282 to 0.349).     

全面安全管理-6 Sigma方法论

概述了最新全面管理工具 6Sigma方法论的概念、原理 ,以及 6Sigma持续循环的 5个阶段在现代企业全面安全管理中的应用     

两相厌氧膜-生物系统处理造纸废水

采用传统两相厌氧工艺 ( BS)与膜分离技术相结合的系统 ( MBS)处理造纸黑液配制废水 .结果表明 :系统 COD去除率可以达到 73.1 % ,高于 BS系统 ( 4 8.6% ) ,且在厌氧污泥活性及运行稳定性方面优于 BS系统 ;在 COD负荷为 6kg·( m³·d)^-1时MBS酸化率为 20.1 % ,酸化水平为 7.5% ,略优于 BS系统 (分别为 7.0 %和 5.0 % ) .探讨了其原因及 MBS系统引入膜的作用 ,并对系统的评价体系进行了初步讨论 .     

区域大型环境空气综合观测中外场观测与实验室分析数据质量控制研究

环境监测的质量保证是监测数据准确性、可比性的重要保障.在区域大气联合观测项目中,完善的质量保证体系应包括管理机制和技术措施两部分,但目前我国对这类项目质量保证尚无统一标准.针对大气重污染成因与治理攻关项目（简称"大气攻关项目"）外场观测任务量大、承担单位多、监测项目复杂的特点,为保证观测数据的质量,避免出现由于监测和质控方法不统一造成的数据可比性差、结果矛盾的问题,提出了大气攻关项目质量保证体系和管理机制.其中,质量保证体系包括制定总体要求（技术文件、监测项目及质控要求）、外场观测质量保证（内部质量管理体系、项目外场观测质量保证体系）、实验室分析质量保证（实验室遴选、项目实验室分析多级质量保证体系、实验室比对和飞行检查）和数据质量控制（数据线上审核、项目实验室分析质控报告、项目数据质量评价）4个方面.管理机制为项目管理办公室、质控实验室和承担单位三级主体,两级监督的分级管理模式.通过项目实践,项目质量保证体系达到了保证观测数据准确性、可比性的预期效果,为揭示区域雾霾形成机理、突破污染控制关键技术提供了有力的技术支持,同时为区域大气联合观测项目的数据质量保证提供了借鉴.      

冬季降温对菹草叶片光合荧光特性的影响

将菹草(Potamogeton cripus)石芽种植于室外水体中,萌发后选择发育程度相近的幼苗,在冬季降温期间利用水下饱和脉冲荧光仪(DIVING-PAM)测定幼苗叶片的FV/Fm和光响应恢复曲线.结果表明,在冬季水温低于7℃的条件下菹草叶片FV/Fm显著降低(P<0.01).水温回复到9～10℃后,FV/Fm逐渐增大;光强的降低有利于FV/Fm的恢复.进一步研究植株的光响应恢复曲线发现,第4-10天,水温<7℃,菹草叶片有效荧光产量(ΔFV'/Fm)的光响应能力和暗恢复能力显著下降;同时,热耗散能力和暗恢复能力也显著降低,发生光抑制的可能性增大.当水温升高到9～10℃时,ΔFV/Fm和非光化学淬灭(NPQ)随光强降低和实验天数的增加逐渐得到恢复.因而,水温9～10℃可能是冬季菹草进行正常光合作用的临界温度;菹草在低温(<7℃)、高光照条件下易发生光抑制,导致PSII受到伤害.     

Non-microcystin producing Microcystis wesenbergii (Komárek) Komárek (Cyanobacteria) representing a main waterbloom-forming species in Chinese waters

It is well known that several morphospecies of Microcystis, such as Microcystis aeruginosa (Kützing) Lemmermann and Microcystis viridis (A. Brown) Lemmermann can produce hepatotoxic microcystins. However, previous studies gave contradictory conclusions about microcystin production of Microcystis wesenbergii (Komárek) Komárek. In the present study, ten Microcystis morphospecies were identified in waterblooms of seven Chinese waterbodies, and Microcystis wesenbergii was shown as the dominant species in these waters. More than 250 single colonies of M. wesenbergii were chosen, under morphological identification, to examine whether M. wesenbergii produce hepatotoxic microcystin by using multiplex PCR for molecular detection of a region (mcyA) of microcystin synthesis genes, and chemical analyses of microcystin content by ELISA and HPLC for 21 isolated strains of M. wesenbergii from these waters were also performed. Both molecular and chemical methods demonstrated that M. wesenbergii from Chinese waters did not produce microcystin.     

Performance of Streptomyces pactum–assisted phytoextraction of Cd and Pb: in view of soil properties,element bioavailability,and phytoextraction indices

Environmental Science and Pollution Research - Microbe-assisted phytoremediation provides an eco-friendly and cost-effective approach to reclaim Cd- and Pb-contaminated soils. In this work,...     

混凝剂的不同应用及控制条件

本文列举了４个工程实例，说明了混凝剂的不同用途及控制条件。指出了水处理中，依据不同的机理，合理选择凝剂及组织全混的重要性，同时确定对应的ＰＨ值关系的重要性。     

中文Windows环境下的海上溢油预报系统

本文以辽东湾为示范海区，建立了中文Ｗｉｎｄｏｗｓ环境下的海上溢油预报系统。采用已经验证的环境动力和溢油行为模型，可提供海面油膜的位置和覆盖面积，水体中油的浓度分布以及溢油的比重、粘度、蒸发量、残留量、平均厚度等物化参数的实时预报信息，或用于溢油的环境风险评价。系统界面友好，输入方便，操作简单，反应快捷、后处理功能完备，并具有可扩充性。     

重视沿海地区控制工业污染出现的新问题

沿海地区对外开放１５年来，外资、合资、集体、个体企业在工业结构中的比重明显增加。它们均要求有良好的投资环境，依靠社会办企业。新兴工业多集中在城镇附近，厂址不少选在较关键的须加强环境保护的地区，如自然保护区，水源保护区等附近。在此情况下，必须按社会主义市场经济规律征收资源费和排污费等；须加强环境规划，建立环境管理系统，有效控制污染源；为保证受损环境得到恢复，必须加强环境建设和环境投资。