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481.
Many cities throughout the world are adopting green infrastructure techniques to reduce stormwater and sewer overflows into waterways, which is particularly problematic for places experiencing more frequent and severe rain events. Governance of green stormwater implementation is proving to be as important as the techniques themselves. Building on the climate and sustainability governance literature, we argue that effective governance requires planning across city departments, experimentation and a strategy for organisational learning. We employ a case study of Philadelphia, the first city in the United States to attempt an entirely green approach to meeting federal regulations to examine issues of governance that emerged and how they were addressed. The case study draws on interviews with fourteen public and private sector actors involved in implementation, a site visit to observe the installations and to discuss the approach with a key planner, and grey literature. We find that silos can be broken down and that if open communications and a willingness to change practices are present, obstacles cited in the literature can be overcome. The key implication is that the three elements of governance need to be built into the green infrastructure planning process. While the analysis focuses on a US city, the departments involved and the governance needs of green stormwater infrastructure are similar in cities in much of the world. 相似文献
482.
S. Ferreira M. Cabral N.F. da Cruz R.C. Marques 《Journal of Environmental Planning and Management》2017,60(5):773-791
Local authorities are generally in charge of household packaging waste management operations, particularly in countries with Green Dot schemes or similar extended producer responsibility systems. This leads to the need of establishing a system of financial transfers between the packaging industry and the local authorities (regarding the costs involved in selective collection and sorting). In the present study, the costs and benefits of recycling, from the perspective of local authorities, are compared for Portugal, Belgium and Italy (in Lombardia region), adopting the same economic–financial methodology. The results show that the industry is not paying the net cost of packaging waste management. If the savings attained by diverting packaging waste from other treatment operations are not considered, it seems that the industry should increase the financial support to local authorities. However, if the avoided costs with other treatments are considered as a benefit for local authorities, the costs are generally outweighed by the benefits, and the financial support could, therefore, be reduced. 相似文献
483.
《Journal of Environmental Policy & Planning》2012,14(4):261-274
The high-voltage distribution and transmission of electricity are associated with a range of environmental effects that are increasingly contentious and are leading to difficult land-use planning issues. In the UK, local planning authorities have been taking an anticipatory approach to such efforts by the formation of policy in statutory land-use plans; this seeks to set constraints on the location and form of high-voltage installations and nearby development. This emerging body of policy reveals a number of consistently occurring themes that focus explicitly on the protection of local environmental conditions. This is indicative of broader trends apparent throughout plan-making in the last decade, in which environmental emphases have become more central, but the policy area also indicates that local authorities are responding to structural changes in the electricity industry and to changing patterns of energy generation. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
484.
水电工程在发挥巨大效益的同时,也不同程度地破坏了原有生态环境的平衡.以水电工程开发与生态环境的关系为切入点,分析了水电工程开发对生态环境的正面影响和负面影响,并提出了几点生态环境的保护对策及措施,通过人力与自然力的共同作用达到改善生态环境的目的,实现水电工程开发经济效益、社会效益、生态环境效益的共同提高. 相似文献
485.
486.
We analyzed the ability of freshwater taxa of the genus Ulva (Ulvaceae, Chlorophyta) to serve as bioindicators of metal in lakes and rivers. Changes in heavy metal (Ni, Cd and Pb) and alkaline earth metal (Ca and Mg) concentrations in freshwater Ulva thalli were investigated during the period from June to August 2010. The study was conducted in two ecosystems in Western Poland, the Malta lake (10 sites) and the Nielba river (six sites). Three components were collected for each sample, including water, sediment and Ulva thalli. The average concentrations of metals in the water sample and in the macroalgae decreased in the following order: Ca > Mg > Ni > Pb > Cd. The sediment revealed a slightly altered order: Ca > Mg > Pb > Ni > Cd. Ca and Mg were found at the highest concentrations in thalli due to the presence of carbonate on its surface. Among the examined heavy metals in thalli, Ni was in the highest concentration, and Cd found in the lowest concentration. There were statistically significant correlations between the levels of metals in macroalgae, water and sediment. Freshwater populations of Ulva exhibited a greater efficiency to bioaccumulate nickel as compared to species derived from marine ecosystems. 相似文献
487.
研究了厌氧流化床微生物燃料电池(AFB-MFC)除碳脱氮产电性能的影响因素。结果表明:(1)AFB-MFC对NH4+-N的去除不起作用。电压下降主要是由于进水有机基质浓度下降造成。(2)不添加NO3--N时,在满足AFB-MFC脱氮所需的电子供体条件下增加进水COD/TN有利于AFB-MFC产电。(3)3种无机氮共存下,AFB-MFC在进水有机碳与无机氮质量比(C/N)不低于1.37时,对COD、NO2--N和NO3--N具有理想的去除效果。AFB-MFB在一定进水C/N范围内(1.37~2.50),能得到稳定的输出电压及功率密度。(4)固定进水C/N时,AFB-MFC在高碳氮负荷下仍能得到较理想的NO2--N、NO3--N、COD去除效果,AFB-MFC对NH4+-N去除效果不明显;增加碳氮负荷,AFB-MFC输出电压及功率密度没有明显的改变。(5)有机基质浓度不变下,AFB-MFC中充足的电子供体可保证较高的NO3--N、COD去除率。AFB-MFC输出电压及功率密度随着时间延长而先增加至稳定值后下降。 相似文献
488.
During the egg-laying process, oviductal fluid was collected using a non-invasive procedure from the cloacal vent of the green turtles. Forty-two independent isolates of antibiotic-resistant bacteria from 11 genera were obtained from 20 turtles during nesting. The dominant isolate was Citrobacter (52.4%), followed by Pseudomonas, Proteus, Enterobacter, Salmonella, Escherichia coli, Shigella, Edwardsiella, Morganella, Providencia and Arcomobacter. Most of the isolates were resistant to ampicillin. Ampicillin-resistant isolates showed variations in their resistance for the following classes of β-lactamases: extended-spectrum β-lactamases (EBSLs), AmpC type β-lactamases C (AmpC), and screen-positive β-lactamase. None of the isolates produced metallo β-lactamase. Some ampicillin-resistant genes were detected by multiplex polymerase chain reaction (PCR) only. Inhibitor based test (IBT) categorized some isolates as AmpC β-lactamase producers. β-Lactamase genes were detected from a few strains. The sequencing of those genes revealed the presence of cephamycinase (CMY) and AmpC β-lactamases. The oviductal fluid was used in this study as a source of bacterial antibiotic-resistant determinants for biomonitoring marine turtles exposed to contaminated effluents. This data can be of value in understanding the decline of this endangered species as a result of exposure to marine pollution which is threatening their survival. 相似文献
489.
Polycyclic aromatic hydrocarbons (PAHs) have been detected in some commercial teas around the world and pose a threat to tea consumers. However, green tea polyphenols (GTP) possess remarkable antioxidant and anticancer effects. In this study, the potential of GTP to block the toxicity of the model PAH phenanthrene was examined in human embryo lung fibroblast cell line HFL-I. Both GTP and phenanthrene treatment individually caused dose-dependent inhibition of cell growth. A full factorial design experiment demonstrated that the interaction of phenanthrene and GTP significantly reduced growth inhibition. Using the median effect method showed that phenanthrene and GTP were antagonistic when the inhibitory levels were less than about 50%. Apoptosis and cell cycle detection suggested that only phenanthrene affected cell cycle significantly and caused cell death; GTP lowered the mortality of HFL-I cells exposed to phenanthrene; However, GTP did not affect modulation of the cell cycle by phenanthrene. 相似文献
490.