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1.
一硫代磷酸酯类杀虫剂的微生物降解   总被引:3,自引:1,他引:3  
在纯培养条件下测定了分离株 YF0 5对对硫磷等一硫代磷酸酯类杀虫剂的降解作用。在接种量 (OD4 15nm)为 0.2、pH7.0、30℃条件下 ,测得 10、25、50、100、200、500 mg/L对硫磷的降解符合一级动力学特征 ,其降解速率常数分别为 0.077、0.123、0.128、0.119、0.084、0 .013,高浓度对硫磷对 YF05菌有抑制作用 ;分离株 YF05在不同温度及 pH下对对硫磷的降解作用为 40℃ >30℃ >20℃ ,pH8.0 >pH7.0 >pH6 .0。同样条件下 ,YF05对杀螟硫磷和甲基对硫磷也有较好的降解作用 ,对甲基对硫磷的降解速率常数与对硫磷相仿 ,对杀螟硫磷的降解速率常数略高于对硫磷。  相似文献   
2.
以微生物与重金属相互作用为对象,结合近年来国内外研究,系统地说明了5种主要分子作用机理,分别为细胞表面吸附、主动运输、细胞内隔绝、胞外沉淀及酶的解毒作用。对重金属产生抗性的基因位于微生物的染色体、质粒和转座子上。最后介绍了多种抗性菌株,并就研究和应用前景进行了分析。  相似文献   
3.
The filter feeder sabellid Sabella spallanzanii Gmelin (Polychaeta, Sabellidae) was proposed as biofilter in the treatment of wastes from intensive aquaculture. The species was previously studied concerning reproductive traits and ecological requirements; moreover, previous laboratory experiments indicated a positive action of its feeding activity on solid removal from water column coupled with an interesting microbiological activity. In the present paper data on settlement and growth rate from a natural population, together with data on the bioremediation activity of an adult population, relative to an experiment conducted in a small fish farm are reported. Results seem to encourage further studies on S. spallanzanii for a future utilization in bioremediation of fish farms with recycled water. Data from natural annual settlement indicated, however, the unreliability in obtaining settlers from natural populations, so that the artificial reproduction of the target species will be one of the main points of further investigations.  相似文献   
4.
Biologically enhanced dissolution offers a method to speed removal of chlorinated solvent dense non-aqueous-phase liquid (DNAPL) sources such as tetrachloroethene (PCE) and trichoroethene (TCE) from aquifers. Bioremediation is accomplished by adding an electron donor to the source zone where fermentation to intermediates leading to acetic acid and hydrogen results. The hydrogen and possibly acetic acid are used by dehalogenating bacteria to convert PCE and TCE to ethene and hydrochloric acid. Reductive dehalogenation is thus an acid forming process, and sufficient alkalinity must be present to maintain a near neutral pH. The bicarbonate alkalinity required to maintain pH above 6.5 is a function of the electron donor: 800 mg/L of bicarbonate alkalinity is sufficient to achieve about 1.2 mM TCE dechlorination with glucose, 1.7 mM with lactate, and a much higher 3.3 mM with formate. Laboratory studies indicate that in mixed culture, formate can be used as an electron donor for complete conversion to ethene, contrary to pure cultures studies indicating it cannot. Various strategies can be used to add electron donor to an aquifer for DNAPL dehalogenation while minimizing pH problems and excessive electron donor usage, including use of injection-extraction wells, dual recirculation wells, and nested injection-extraction wells.  相似文献   
5.
Aspergillus niger isolated from soil of leather tanning effluent had higher activity to remove chromium then the other fungal isolates. The potency of A. niger was evaluated in shake flask culture by absorption of chromium at pH 6, temperature 30 °C. The toxicity of chromium evaluated in petriplates and soil microcosm seed bioassay test had indicated increase in toxicity with the higher concentration of chromate. A. niger introduced in soil microcosm (40% moisture content) with different concentration of chromate (250, 500, 1000, 1500 and 2000 ppm) removed more than 70% chromium in soil contaminated by 250 and 500 ppm of chromate. However, chromium-contaminated soil (2000 ppm of potassium chromate) mixed with compost (5% and 10%) significantly removed chromium in presence of fungus, A. niger. The results of chromate toxicity in the wheat plants revealed that the peroxidases was induced due to increase of metal stress which was reversed in soil microcosm amended with compost.  相似文献   
6.
A phenanthrene-degrading bacterial strain Pseudomonas sp. GF3 was examined for plant-growth promoting effects and phenanthrene removal in soil artificially contaminated with low and high levels of phenanthrene (0, 100 and 200 mg kg−1) in pot experiments. Low and high phenanthrene treatments significantly decreased the growth of wheat. Inoculation with bacterial strain Pseudomonas sp. GF3 was found to increase root and shoot growth of wheat. Strain GF3 was able to degrade phenanthrene effectively in the unplanted and planted soils. Over a period of 80 days the concentration of phenanthrene in soil in which wheat was grown was significantly lower than in unplanted soil (p<0.05). At the end of the 80-d experiments, 62.2% and 42.3% of phenanthrene had disappeared from planted soils without Pseudomonas sp. GF3 when the phenanthrene was added at 100 and 200 mg kg−1 soil, respectively, but 84.8% and 70.2% of phenanthrene had disappeared from planted soils with the bacterial inoculation. The presence of vegetation significantly enhances the dissipation of phenanthrene in the soil. There was no significant difference in soil polyphenol oxidase activities among the applications of 0, 100 and 200 mg kg−1 of phenanthrene. However, the enzyme activities in planted and unplanted soils inoculated with the strain Pseudomonas sp. GF3 were significantly higher than those of non-inoculation controls. The bacterial isolate was also able to colonize and develop in the rhizosphere soil of wheat after inoculation.  相似文献   
7.
土壤有机污染生物修复技术影响因素的研究进展   总被引:12,自引:6,他引:12  
沈定华  许昭怡  于鑫  胡文勇 《土壤》2004,36(5):463-467
土壤有机污染的生物修复技术的论述很多,本文则从对影响这些技术实施的因素进行综合评述,例如污染物的性质、微生物自身特性等。  相似文献   
8.
微生物在污染环境生物修复中的应用   总被引:4,自引:0,他引:4  
生物修复是一项利用生物特别是微生物治理污染的技术。与理化修复方法相比具有投资少、对环境影响小的优点。本文重点分析了影响微生物修复的关键因素,包括生物因素、营养因素、O2和电子受体、表面活性剂和共代谢物等,并介绍了微生物在生物修复中成功应用的实例,讨论了生物修复所具有的优势和存在的不足及今后研究重点。  相似文献   
9.
在实验室小试和现场中试的基础上 ,采用预制床处理工艺对辽河油田4种不同类型石油污染土壤进行实用规模的生物处理技术研究。工程运行结果表明 ,当稀油、稠油、特稠油和高凝油污染土壤中石油烃总量 (TPH)为25.8—77.2g·kg-1时 ,经过84d的运行 ,TPH去除率为38 %—60 %。TPH的降解速率除与微生物的生长环境有关外还与石油的理化性质密切相关。4种油污染土壤的降解速率依次为 :稀油>高凝油>稠油>特稠油 ,TPH的组分对其降解速率有重要影响。本研究为大规模石油污染土壤异位生物修复提供了技术支持  相似文献   
10.
韦万丽  张笑一  彭润芝 《安徽农业科学》2006,34(19):5008-5008,5011
污染土壤的生物修复技术是一种经济高效的恢复土壤功能的方法。针对地沟式污水土地处理系统的土壤受体,采用曝气、栽种美人蕉、配施稀土La3+等措施对污染土壤实施修复技术。其中曝气使污染物NH3-N、TP和COD的去除率分别增加15.11%~15.68%、10.28%~11.21%、17.89%~18.56%。栽种美人蕉的结果是7.65%~8.11%、6.65%~6.98%、5.12%~5.44%。而低浓度稀土处理对污染土壤活性修复略有增效,高浓度处理则明显的表现出对土壤的抑制作用。  相似文献   
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