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为探究不同水期河流底泥古菌群落结构特征,选取浑河底泥为研究对象,并于2014年4月(枯水期),9月(丰水期),11月(平水期)对浑河流域进行样品采样,通过PCR-DGGE技术获得3个水期古菌的DGGE指纹图谱,并进行数据分析.结果表明,平水期的古菌多样性和种群丰度都要好于枯水期和丰水期,多样性指数均高于2.10,种群丰度均高于0.94,且上游到下游均匀度波动平缓,数值维持在0.90左右,说明平水期浑河底泥古菌群落结构变化相对稳定.聚类分析结果表明,不同水期浑河底泥古菌群落结构多样性并没有明显的地区特征,但3个水期位于城市段的采样点的古菌亲缘性较为接近.冗余梯度分析(RDA)结果表明,枯水期时水中BOD5、p H和DO是影响古菌群落的主要因素;丰水期时水中的p H和NO-3-N是影响古菌群落的主要因素;平水期时水中的TP和NO-2-N是影响古菌群落的主要因素. 相似文献
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MBR中微生物群落结构的演变与分析 总被引:17,自引:3,他引:14
为了揭示膜.生物反应器中微生物群落结构多样性的演变过程,通过细胞裂解法直接提取不同时期污泥中的基因组DNA,利用基于16SrDNA的PCR-DGGE技术获得了微生物群落的DNA特征指纹图谱,并对条带进行了统计分析和切胶测序,使用序列数据进行了同源性分析并建立了系统发育树.DGGE分析表明,在反应器运行前17d内污泥中微生物群落结构变化很大,与接种污泥的相似性系数下降到了29.2%,从而说明MBR中处理工艺和进水水质的改变导致微生物群落结构多样性降低.在试验过程中,Pscudomonas和Aeromonas hydrophila等种群一直保持着较为稳定的优势地位,也有原始种群如Bacillus sp.的消亡和以Enterococcus faecalis、Comamonas sp.、Fusobacterium sp.等为代表的次级种群的强化和演变.UPGMA聚类分析将DGGE图谱区分为3大类群并对应于各自的运行时期.测序结果表明,MBR中微生物菌群间进化距离较大,其中Proteobaeteria纲和Bacillus属细菌较多.在反应器运行后期演变为优势地位的菌群(如Comamonas sp.)加剧了膜污染物的产生和积累. 相似文献
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Dynamic changes of microbial community diversity in a photohydrogen
producing reactor monitored by PCR-DGGE 总被引:2,自引:1,他引:1
A PCR-DGGE (denaturing gradient gel electrophoresis of polymerase chain reaction) protocol was used for monitoring the dynamic changes in the microbial population during photohydrogen production. Total DNA was extracted directly from the mixed bacterial community in the reactor and subjected to PCR with V3-16S rDNA and pufM gene primers, and the amplifications were then analyzed by DGGE. The DGGE patterns demonstrated the dynamics of community structure and the shift of microbial diversity, which correspond... 相似文献
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水解酸化-好氧法处理油田废水机理研究 总被引:4,自引:0,他引:4
采用水解酸化-好氧法对经物化预处理的油田废水进行试验研究.当进水COD为190~220 mg·L-1时,水解酸化段和好氧段停留时间均为10h的条件下,出水COD为65~75 mg·L-1,达到GB3550-83第一级Ⅰ类标准.运用GC/MS技术分析油田废水有机污染物在工艺流程中相对组分变化的规律,揭示了水解酸化-好氧法处理油田废水过程中的污染物迁移和降解规律.并运用PCR-DGGE技术,考察不同生物反应器内微生物种群及其分布特征,初步确定水解酸化和好氧反应器内的优势菌种. 相似文献
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The bacterial community structures in two sewage treatment plants with different processes and performance were investigated by denaturing gradient gel electrophoresis (DGGE) of nested polymerase chain reaction (nested PCR) amplified 16S rRNA gene fragments with group-specific primers. Samples of raw sewage and treated effluents were amplified using the whole-cell PCR method, and the activated sludge samples were amplified using the extracted genomic DNA before the PCR products were loaded on the same DGGE gel for bacterial community analysis. Ammonia-oxidizing bacterial and actinomycetic community analysis were also carried out to investigate the relationship between specific population structures and system or sludge performance. The two plants demonstrated a similarity in bacterial community structures of raw sewage and activated sludge, but they had different effluent populations. Many dominant bacterial populations of raw sewage did not appear in the activated sludge samples, suggesting that the dominant bacterial populations in raw sewage might not play an important role during wastewater treatment. Although the two plants had different sludge properties in terms of settleability and foam forming ability, they demonstrated similar actinomycetic community structures. For activated sludge with bad settling performance, the treated water presented a similar DGGE pattern with that of activated sludge, indicating the nonselective washout of bacteria from the system. The plant with better ammonium removal efficiency showed higher ammonia-oxidizing bacteria species richness. Analysis of sequencing results showed that the major populations in raw sewage were uncultured bacterium, while in activated sludge the predominant populations were beta proteobacteria. 相似文献
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改良剂对土壤铜镉有效性和微生物群落结构的影响 总被引:10,自引:0,他引:10
以一次性添加木炭、石灰和磷灰石稳定化修复4年后的土壤为研究对象,探讨了土壤中铜镉有效性和土壤微生物群落结构的变化.结果表明,3种改良剂的添加提高了土壤pH值,降低了土壤交换性酸和交换性铝的含量,使铜镉由活性态向非活性态和潜在活性态转化,其中磷灰石和石灰的处理效果优于木炭处理; Biolog测试发现,培养192h,木炭、石灰和磷灰石处理土壤AWCD值(0.61、0.76和0.70)分别是对照的1.33、1.65和1.52倍;且Shannon和McIntosh指数均较对照有所提高,表现为:石灰 > 磷灰石 > 木炭,表明改良剂处理后增加了土壤微生物对碳源的利用能力,提高了其功能多样性.PCR-DGGE分析结果显示,改良剂处理后土壤细菌优势群的数量显著增加,木炭、石灰和磷灰石处理Shannon指数分别比对照提高了0.22、0.39和0.24.相关性分析表明,土壤酸度和重金属有效性是影响稳定化修复重金属污染土壤细菌结构多样性差异的主要因素. 相似文献
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采用PCR-DGGE技术并结合系统处理效果研究了贫营养条件下IAMBR污泥微生物群落结构,结果表明:IAMBR污泥中总细菌多样性特征、相似性特征和种群归属特征具有高度的协同性.运行前18天,氨氮去除率由95%降至73%后增加至82%,同时SVI值由123.7mL/g升至135.2mL/g再降至128.4mL/g.微生物群落在试验末期演替剧烈,总细菌相似性指数下降到63.6%,SVI值最终升至132.5mL/g.通过克隆测序分析,IAMBR系统中微生物菌种大部分为未培养菌种,其中亚硝化螺菌属占据优势地位,说明贫营养环境对IAMBR微生物群落产生不良影响,污泥微生物功能性指向明显,即硝化功能菌占据优势地位. 相似文献