城市污水人工土快滤处理系统的生物修复

针对人工土快滤床长期运行在淹水状况下由于入水有机物浓度大于系统处理能力而造成的有机质积累和堵塞现象,通过国内外资料调研,从微生物、植物、土壤动物3个方面,讨论了应用生物修复技术来解决上述问题的可能性。     

施用生物菌剂对油水淹地污染土壤的修复研究

从油水淹地污染土壤中获得石油降解菌,筛选出产表面活性剂降解菌1株(H-6)和优势菌6株(H-1、H-17、H-18、H-19、H-20、H-23),以H-6为中心,再任选3株优势菌株构建菌群,最终得到高效石油降解菌群C5(H-1、H-6、H-18、H-19),以秸秆为载体将C5菌群制备成固体生物菌剂(MA),通过室内培养试验和田间试验测定油水淹地污染土壤的石油含量、盐碱性指标及微生物性质,探究MA菌剂对油水淹地污染土壤的修复情况。室内培养试验和田间试验结果表明,污染土壤中石油的降解效果都很显著,MA菌剂中的细菌具有嗜盐菌的特征,使污染土壤的p H、电导率、全盐量、钠吸附比(SAR)和总碱度(TA)显著低于未添加菌剂处理,添加菌剂后污染土壤的微生物数量、微生物量碳、可溶性盐离子组成也都优于未添加菌剂处理。因此,MA菌剂对油水淹地这种油盐复合污染土壤具有较好的生物修复效果,为油水淹地污染土壤的大规模修复提供了技术支持。     

黄孢原毛平革菌对土壤中五氯酚的降解

 研究了白腐真菌典型种黄孢原毛平革菌(Phanerochaete chrysosporium)对土壤中五氯酚(pentachlorophenol,PCP)的生物降解。结果表明,在灭菌土壤中PCP初始浓度为71.62 mgkg-1干土条件下,P.chrysosporium生长和对PCP降解的最适接种量为0.10 mlg-1干土,P.chrysosporium最适生长温度为37℃,对PCP降解的最适宜温度为30～37℃,菌体生长和PCP降解的最适土壤含水量为25%。灭菌土壤中PCP的初始浓度为50.05～175.     

海洋微生物在海洋污染治理中的应用现状

海洋微生物是在海洋环境中能够生长繁殖、形体微小、单细胞或个体结构较为简单的多细胞、甚至没有细胞结构的一群低等生物。海洋微生物种类繁多，按其结构、形态和组成不同，可分为三大类；非细胞型（如海洋病毒）、原核细胞型（如海洋细菌、海洋放线菌和海洋蓝细菌等）和真核细胞型（如海洋酵母菌、海洋霉菌等）。从微生物学或环境微生物学角度来讲，海洋微藻也应归入海洋微生物的范畴。     

重金属污染土壤的生物修复

分析了重金属的危害、土壤中重金属的六大来源及污染特点,提出了目前主流治理技术——生物修复技术,并与其它技术进行了比较。详述了该技术的分类及其优劣,展望了生物修复技术的前景。     

内源性土壤苏云金杆菌(BRC-ZYR2)对含氧铬还原的影响研究

Chromium（Cr） may cause losses in the yield of field plant, which is one of the favorite habitats of Bacillus thuringiensis（Bt）. The purposes of our study were to assess the Cr（VI）-resistance and Cr（VI）-reducing abilities of an indigenous soil isolate of Bt and to determine the factors governing Cr（VI） reduction. Towards this end a novel dichromate-reducing Bt BRC-ZYR2, characterized with insecticidal crystal proteins（ICPs）, was isolated from a uranium deposit. Minimum inhibitory concentrations（MICs） of Cr（VI） were determined by broth dilution method and the concentrations of Cr（VI） and total Cr in the supernatant were quantified colorimetrically using 1,5-diphenylcarbazide（DPC） reagent and a mixture of sulfuric-nitric acids, respectively. The isolate contained five ICP genes（cry1Ba, cry1 Bb, cry1Be/cry1 Bf, cry9 Ca and cry9Da） and exhibited a high level of Cr（VI） resistance with MICs of 150 mg L-1at pH 7.0 and 30？C, and 500 mg L-1under optimal conditions（pH 9.0 and 40？C）. The total Cr concentration was similar to initial concentration of Cr（VI） under the optimal condition, suggesting that the essential removal of the Cr（VI） was dependent on Bt reduction. Under optimal conditions, the initial Cr（VI） concentrations from 25 to 75 mg L-1significantly decreased in 24 h after incubation. Addition of Mn2＋, Co2＋, Mo2＋and Cu2＋activated Bt-mediated Cr（VI） reduction, while Zn2＋, Ni2＋and glucose were found to inhibit the reduction. Our results indicated that this isolate could be a promising biopesticide with the potential for both insect biocontrol and Cr bioremediation in the field.     

Advances in fungal-assisted phytoremediation of heavy metals: A review

Trace metals such as manganese (Mn), copper (Cu), zinc (Zn), and iron (Fe) are essential for many biological processes in plant life cycles. However, in excess, they can be toxic and disrupt plant growth processes, which is economically undesirable for crop production. For this reason, processes such as homeostasis and transport control of these trace metals are of constant interest to scientists studying heavily contaminated habitats. Phytoremediation is a promising cleanup technology for soils polluted with heavy metals. However, this technique has some disadvantages, such as the slow growth rate of metal-accumulating plant species, low bioavailability of heavy metals, and long duration of remediation. Microbial-assisted phytoremediation is a promising strategy for hyperaccumulating, detoxifying, or remediating soil contaminants. Arbuscular mycorrhizal fungi (AMF) are found in association with almost all plants, contributing to their healthy performance and providing resistance against environmental stresses. They colonize plant roots and extend their hyphae to the rhizosphere region, assisting in mineral nutrient uptake and regulation of heavy metal acquisition. Endophytic fungi exist in every healthy plant tissue and provide enormous services to their host plants, including growth enhancement by nutrient acquisition, detoxification of heavy metals, secondary metabolite regulation, and enhancement of abiotic/biotic stress tolerance. The aim of the present work is to review the recent literature regarding the role of AMF and endophytic fungi in plant heavy metal tolerance in terms of its regulation in highly contaminated conditions.     

Engineered in situ bioremediation of soil and groundwater polluted with weathered hydrocarbons

In this work, we present our experience in the engineered in situ biostimulation of a hydrocarbon-polluted subsoil of an old metal-working plant. The site had a long history of fuel, lubricant oil, and diesel spills and leakages that were initially treated by means of physico-chemical techniques. After one year of treatment, weathered hydrocarbons were firmly sorbed in the unsaturated zone, limiting the effectiveness of the physico-chemical methods being applied. Also, low nutrient and dissolved oxygen levels limited natural attenuation yields. Therefore, a bioremediation approach based on the injection of hydrogen peroxide, an oleophilic fertilizer, and a surfactant was applied. Total petroleum hydrocarbons and gas chromatography-mass spectrometry determinations were performed as a chemical means of monitoring the process. Microbial populations, including the presence of hydrocarbon-degrading bacteria, were simultaneously analyzed during the process, using enrichment techniques and confocal laser scanning microscopy observations with fluorescent indicators. Hydrocarbon-degrading bacteria were already present in the polluted subsoil prior to the implementation of this bioremediation technique and increased noticeably during the first 2 months of treatment. Hence, the suitability of the nutrient and oxygen amending approach was confirmed as further demonstrated by chemical determinations.     

采用通气堆沤对石油烃污染土壤进行生物修复

Laboratory simulation studies and a composting pilot study were conducted to evaluate the capacity of three strains of fungi, indigenous fungus Fusarium sp. and Phanerochaete chrysosporium and Coriolus Versicolor, to remediate petroleum-contaminated soils. In laboratory, the fungi were inoculated into a liquidculture medium and the petroleum-contaminated soil samples for incubation of 40 and 50 days 5 respectively. In the 200-day pilot study, nutrient contents and moisture were adjusted and maintained under aerobiccondition in composting units using concrete container (118.5 cm × 65.5 cm × 12.5 cm) designed specially for this study. The laboratory simulation results showed that all the three fungi were effective in degrading petroleum in the liquid culture medium and in the soil. At the end of both the laboratory incubations, the degradation rates by Phanerochaete chrysosporium were the highest, reaching 66% after incubation in liquid culture for 50 days. This was further demonstrated in the composting pilot study where the degradation rate by P. chrysosporium reached 79% within 200 days, higher than those of the other two fungi (53.1% and 46.1%), indicating that P. chrysosporium was the best fungus for bioremediation of soil contaminated with petroleum. Further research is required to increase degradation rate.     

江蓠的资源开发利用新进展

从江蓠对海水的生物修复，琼脂糖及江蓠保健食品的研究现状综述江蓠的资源利用新情况。