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81.
含锌废水处理技术的研究进展   总被引:9,自引:0,他引:9  
综述了传统的物理化学法和生物法处理含锌废水的原理,系统阐述了其研究进展.微生物固定技术是一种新兴而有效的生物处理技术,尤其是硫酸盐还原菌固定化技术,将厌氧活性污泥包埋,构建稳定高效的微生物体系,以加强其抗毒性和处理效率.因此,在含锌废水处理方面具有很大的发展潜力,有望得到广泛应用.  相似文献   
82.
四川彭州铜尾矿库植被特征分析与植物群落演替初探   总被引:2,自引:0,他引:2  
张翔  宗浩  王文国 《四川环境》2006,25(6):44-48
本文分析了四川彭州铜矿尾矿库的植被特征、群落特征与演替。在该尾矿库上自然定居的高等植物共91种,隶属38科79属,以菊科(Compositae)和禾本科(Gramineae)植物为主。形成6种相对稳定的群落类型;在2003年弃耕后形成的地段分布有史蒿+小飞蓬群落(Artemisia argyi+Conyza conadensis Comm.)、艾蒿+打破碗花花群落(Artemisia argyi+Anemone hupehensis Comm.)、艾蒿群落(Artemisia argyi Comm.)和白车轴苹群落(Trifolium repens Comm.);在经过30~40年自然演替的地段分布有芭茅+羊耳菊群落(Miscanthus sinensis+Inula cappa Comm.)和羊耳菊+千里光+密蒙花群落(Inula cappa+Senecio scandens+Buddleja officinalis Comm.);在近十年内新形成的地段现主要覆盖地衣和葫芦藓(Funaria hygrometrica)。通过对群落结构和不同地段植被特征的对比,对本铜尾矿库的演替现状和规律进行了分析,井讨论了人为影响对演替进程的影响,提出了人工恢复措施的建议。  相似文献   
83.
曝气生物滤池(BAF)在小区污水处理中的运用   总被引:1,自引:0,他引:1  
介绍了曝气生物滤池(BAF)工艺在小区污水处理中的运用,分析了实际工程的设计及运行情况,并对曝气生物滤池运行中有关问题进行了总结,最后对其应用前景作了展望。  相似文献   
84.
垃圾填埋场有机污染物的生物降解机理   总被引:3,自引:0,他引:3  
概述了垃圾填埋场中微生物的作用特性,微生物对有机污染物的降解及其影响因素,介绍了有机污染物降解的两种生化动力学模型:“速度指数模型”和“双曲线速度模型”,以及垃圾降解的动力学方程。  相似文献   
85.
城市公共安全规划与灾害应急管理的集成研究   总被引:13,自引:0,他引:13  
随着城市公共安全理论研究与应用的不断深入,对于安全规划与灾害应急管理的孤立研究已渐露弊端.探讨了研究城市公共安全规划与灾害应急管理的融合模式,剖析了城市公共安全规划的空间范围与应变管理空间需求之间的关系,提出了以整合观和可持续发展观构建城市公共安全规划,以空间观构建城市应急管理机制的设想.在此基础上,根据有效服务范围和资源量,提出了城市各类防救灾设施的规划标准与建构模式,以建立城市救灾单元区域.  相似文献   
86.
The performance of a wetland system in treating lead (Pb)/zinc (Zn) mine drainage was evaluated by using the polyurethane foam unit (PFU) microbial community (method), which has been adopted by China as a standardized procedure for monitoring water quality. The wetland system consisted of four cells with three dominant plants: Typha latifolia, Phragmites australis and Paspalum distichum. Physicochemical characteristics [pH, EC, content of total suspended solid (TSS) and metals (Pb, Zn, Cd, and Cu)] and PFU microbial community in water samples had been investigated from seven sampling sites. The results indicated that the concentrations of Pb, Zn, Cd, Cu, and TSS in the mine drainage were gradually reduced from the inlet to the outlet of the wetland system and 99%, 98%, 75%, 83%, and 68% of these metals and TSS respectively, had been reduced in concentration after the drainage passed through the wetland system. A total of 105 protozoan species were identified, the number of protozoa species and the diversity index (DI) gradually increased, while the heterotrophic index (HI) gradually decreased from the inlet to the outlet of the wetland system. The results indicated that DI, HI, and total number species of protozoa could be used as biological indicators indicating the improvement of water quality.  相似文献   
87.
The need for scientifically defensible water quality standards for nonpoint source pollution control continues to be a pressing environmental issue. The probability of impact at differing levels of nonpoint source pollution was determined using the biological response of instream organisms empirically obtained from a statistical survey. A conditional probability analysis was used to calculate a biological threshold of impact as a function of the likelihood of exceeding a given value of pollution metric for a specified geographic area. Uncertainty and natural variability were inherently incorporated into the analysis through the use of data from a probabilistic survey. Data from wadable streams in the mid‐Atlantic area of the U.S. were used to demonstrate the approach. Benthic macroinvertebrate community index values (EPT taxa richness) were used to identify impacted stream communities. Percent fines in substrate (silt/clay fraction, > 0.06 mm) were used as a surrogate indicator for sedimentation. Thresholds of impact due to sedimentation were identified by three different techniques, and were in the range of 12 to 15 percent fines. These values were consistent with existing literature from laboratory and field studies on the impact of sediments on aquatic life in freshwater streams. All results were different from values determined from current regulatory guidance. Finally, it was illustrated how these thresholds could be used to develop criterion for protection of aquatic life in streams.  相似文献   
88.
There is an increasing trend to conduct the researches related to Microbial Fuel Cells (MFCs) in the recent years. Limited power output has been the major obstacle for the practical application and upscaling of MFCs. Attempts have been made on electrode modifications such as anode treatments, cathode modifications with catalysts and bio cathodes developments to produce varying degrees of improved output current depending upon the types of modifications. Power density and Coulombic efficiency have been considered as the important parameters to analyze the system performances. This paper overviews on the advances made in MFCs’ researches focusing on different types of electrodes modifications along with the involved methodology. Furthermore, the system performances of different modified MFCs are compared in terms of the power density and the Coulombic efficiency.  相似文献   
89.
This paper analyses how 10 localities in the USA and England, recognised as leaders in clean energy and climate action, have used collaborative approaches to develop local climate change plans and energy conservation, efficiency, and renewable energy initiatives. It examines these planning and policy-making processes in the context of Margerum's [2008. A typology of collaboration efforts in environmental management. Environmental Management, 41 (4), 487–500] typology of “action”, “organizational”, and “policy-level” collaborations, as well as Gray's [1989. Collaborating: finding common ground for multiparty problems. San Francisco: Jossey-Bass] classification of collaboration in the “problem-setting”, “direction-setting”, and “implementation” phases. We conducted interviews with local elected officials, municipal staff, energy professionals, and citizen volunteers in each community, supplemented with an analysis of their adopted energy, climate change, and land-use plans. We find that despite the different government structures and political contexts between the two countries, there was a surprising amount of commonality in how the case study localities used collaborative planning to develop local climate plans and clean energy initiatives. These processes were most often initiated by local elected officials and/or high-level staff members, and then carried out in collaboration with local third-sector organisations and other community stakeholders. In the USA, collaboration was strongest at the policy level and in the direction-setting phase, with the distinguishing feature that citizen advisory boards or stakeholder working groups often took a more active role in shaping local plans and policies. The English localities had some of those same types of collaborations, but were more likely to also employ action collaboration, in the implementation phase, in which third-sector organisations coordinated with the locality to directly provide clean energy services.  相似文献   
90.
We designed 3 image‐based field guides to tropical forest plant species in Ghana, Grenada, and Cameroon and tested them with 1095 local residents and 20 botanists in the United Kingdom. We compared users’ identification accuracy with different image formats, including drawings, specimen photos, living plant photos, and paintings. We compared users’ accuracy with the guides to their accuracy with only their prior knowledge of the flora. We asked respondents to score each format for usability, beauty, and how much they would pay for it. Prior knowledge of plant names was generally low (<22%). With a few exceptions, identification accuracy did not differ significantly among image formats. In Cameroon, users identifying sterile Cola species achieved 46–56% accuracy across formats; identification was most accurate with living plant photos. Botanists in the United Kingdom accurately identified 82–93% of the same Cameroonian species; identification was most accurate with specimens. In Grenada, users accurately identified 74–82% of plants; drawings yielded significantly less accurate identifications than paintings and photos of living plants. In Ghana, users accurately identified 85% of plants. Digital color photos of living plants ranked high for beauty, usability, and what users would pay. Black and white drawings ranked low. Our results show the potential and limitations of the use of field guides and nonspecialists to identify plants, for example, in conservation applications. We recommend authors of plant field guides use the cheapest or easiest illustration format because image type had limited bearing on accuracy; match the type of illustration to the most likely use of the guide for slight improvements in accuracy; avoid black and white formats unless the audience is experienced at interpreting illustrations or keeping costs low is imperative; discourage false‐positive identifications, which were common; and encourage users to ask an expert or use a herbarium for groups that are difficult to identify. Pruebas Empíricas de Guías de Campo de Plantas Hawthorne, Cable & Marshall  相似文献   
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