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831.
832.
833.
邻苯二甲酸酯对土壤微生物群落多样性的影响 总被引:11,自引:0,他引:11
邻苯二甲酸酯(PAEs)是存在最广泛的有机有毒污染物之一.利用BIOLOG和ARDRA方法,分别考察了不同浓度PAEs对土壤微生物代谢多样性和遗传多样性的影响.结果表明,不同浓度PAEs处理的土壤的平均颜色变化率(AWCD)值随时间增加的幅度不同,PAEs浓度越高、AWCD值增幅越小,对微生物代谢活性的抑制作用越大;不同浓度PAEs处理样品中微生物群落生理代谢活性和碳代谢类群表现出明显差异,空白和低浓度土壤微生物以糖类和羧酸类代谢群为优势类群,而中浓度和高浓度土壤微生物以多胺类代谢群为优势类群;主成分分析也显示碳代谢类型出现差异,PC1就能将4个样品很好地分开,与PC1正相关程度较高的碳源有L-天冬酰胺酸、 4-羟基苯甲酸和D-苹果酸,负相关的碳源有D-半乳糖醛酸、i-赤藻糖醇、γ-羟基丁酸和1-磷酸葡萄糖.ARDRA带型分析表明不同的土壤样品的多样性指数随着PAEs浓度的增加而增加,短时间内PAEs能增加土壤微生物群落的代谢多样性. 相似文献
834.
Performance of microbiological control by a point-of-use filter system for
drinking water purification 总被引:1,自引:0,他引:1
Purification capacity of a faucet mounted type water filter for home use was evaluated, particularly with regard to microbiological
performance under di erent running conditions. Biofilms were formed inside the filter, a ecting the bacterial quality of the e uent
water. Low flow rate, long stagnation period and high filter temperature were found favorable for bacterial growth inside. By commercial
analytical profile index (API) kits, ten di erent bacterial species were identified in drinking water, four of which were probably
contributed to the biofilm formation since they were also present in the biofilm. Fluorescence in situ hybridization (FISH) was used to
confirm the API identification results, and direct viable count (DVC) method was employed to improve the sensitivity of FISH for the
isolated Acinetobacter spp. and Pseudomonas putida as models. Relationship between the filter operating condition and the bacterial
community alteration was partly revealed, which could provide the basic knowledge for the filter design and its practical use. 相似文献
835.
底泥疏浚对竺山湖底栖生物群落结构变化及水质影响 总被引:5,自引:2,他引:3
结合2008年年底在竺山湖进行的底泥清淤工程,调查了底泥疏浚6个月后对大型底栖动物的群落结构的影响及水质变化.结果表明,疏浚区和未疏浚区底栖动物均以霍普水丝蚓、摇蚊和铜锈环棱螺3种生物为主;同未疏浚区相比,疏浚后生物多样性降低,但生物量增加.受外源污染影响,上覆水体中TN、TP含量变化幅度分别为1.64~4.45mg/L和0.133~0.258mg/L,较高的水体营养盐含量,使得疏浚后的新生底泥仍处于营养盐较高的状态,从而使得底栖动物群落组成以生活于污染较重的物种为主.采用Shannon-Weaver、Simpson和Goodnight指数对底栖生物进行评价,结果表明疏浚区处于中度污染,未疏浚区处于中-重度污染状态.结合底栖动物调查和水质监测结果,只有在严格控制外源污染对水体的影响后,底泥疏浚才能起到应有的作用. 相似文献
836.
837.
838.
839.
Effects on mixed microflora to enhance biohydrogen production from corn stover hydrolysate was studied. 相似文献
840.
We investigated the correlation between performance and the bacteria community composition by H2S and toluene co-treatment.
Operation of the bioreactor was divided into four stages, in which the inlet concentration of toluene and H2S were gradually increased.
In Stage I, toluene was the sole target compound with an average removal e ciency of 86.49%. After adding H2S in Stage II, removal
e ciency of toluene decreased immediately and recovered gradually to 85.96%. When the inlet concentration of toluene and H2S
was increased in Stage III and Stage IV, respectively, the average removal e ciency for toluene increased continuously from 86.31%
to 87.24%. The elimination capacities of toluene increased with increasing inlet loading rates of toluene and H2S. Results of the
PCR-DGGE analysis showed a turnover growth and decline of the microbial populations in the bioreactor. In Stage I, the dominant
toluene-degrading bacteria mainly contained Pseudomonas sp. strain PS+ and Hydrogenophaga sp. In Stage IV, however, the dominant
toluene-degrading bacteria was aciduric bacteria (Clostridium populeti). The dominant microbial community in the bioreactor enhanced
the elimination capacity of toluene, and adding H2S changed the environment of microbial growth, thus resulted in an evolution of
dominant microorganisms. Analyses of microbial community and their activities provides valuable information to e ciently enhance
simultaneous removal of toluene and H2S in the bioreactor. 相似文献