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491.
After briefly reviewing key resilience engineering perspectives and summarising some green infrastructure (GI) tools, we present the contributions that GI can make to enhancing urban resilience and maintaining critical system functionality across complex integrated social–ecological and technical systems. We then examine five key challenges for the effective implementation of GI that include (1) standards; (2) regulation; (3) socio-economic factors; (4) financeability; and (5) innovation. We highlight ways in which these challenges are being dealt with around the world, particularly through the use of approaches that are both context appropriate and socially inclusive. Although progress surmounting these challenges has been made, more needs to be done to ensure that GI approaches are inclusive and appropriate and feature equally alongside more traditional ‘grey’ infrastructure in the future of urban resilience planning. This research was undertaken for the Resilience Shift initiative to shift the approach to resilience in practice for critical infrastructure sectors. The programme aims to help practitioners involved in critical infrastructure to make decisions differently, contributing to a safer and better world.  相似文献   
492.
An attempt for the spectroscopic identification of oxygenated compounds produced in combustion processes under different environmental conditions is reported in this paper. A deeper knowledge about presence and evolution of such species in dependence of the operating conditions of practical burner represents a fundamental hint to the objective of an advancement of the control of combustion process and reduction of pollutant emissions. This paper mainly focuses on species characterized by the presence of carbonyl functionality since aldehydes, ketones and diketones are among the principal intermediate species and products of hydrocarbon oxidation. They are by themselves to be considered atmospheric pollutants and are also indicators of actual pathways followed during the chemical reactions occurring in the combustion process. For these reasons they are most suitable for the exploitation of the above indicated objectives. In this paper, a classification of spectroscopic features and markers of these classes of carbonyl compounds is presented on the basis of both literature and spectra collected from sample species. This interpretative scheme is then used for the attribution of fluorescence signals collected from a tetradecane spray in different environmental conditions.  相似文献   
493.
1株高耐性肠杆菌的筛选及对镉、砷同步钝化   总被引:1,自引:0,他引:1  
从镉、砷复合污染农田土壤中筛选出1株具有硫酸盐还原功能的肠杆菌,通过去除率实验结合表征实验来探究其对镉、砷钝化机制.结果表明,经鉴定筛选出来的菌株M5为肠杆菌属(Enterobacter sp.),具有硫酸盐还原功能,对镉、砷最大耐受浓度为1.0 mmol·L-1左右.在模拟体系中,菌株M5对镉去除率最大达94.13%,对砷去除率最大为27.26%.SEM-EDS和XRD的结果证实了Cd和As被固定成CdS和As2S3,XPS结果表明该菌表面的羧基、羟基和酰胺基主要参与生物吸附.结果为微生物应用修复重金属及类金属污染土壤提供思路和理论依据.  相似文献   
494.
通过构建知识创新能力与城市化、工业化进程的评价指标体系,对长三角地区2000-2011年25个地级以上城市的知识创新能力指数及城市化与工业化进程系数进行测算,并利用协调度模型综合分析评价了知识创新能力与城市化、工业化进程的协调关系.结果显示:①知识创新能力与城市化整体协调度优于其与工业化的协调度;②知识创新能力与城市化协调度逐步磨合到相对理想状态;③知识创新能力与工业化协调度呈现出先上升后下降又上升的较大波动性.  相似文献   
495.
Sex ratios are a crucial parameter for evaluating population viability. In species with complex life history patterns and temperature sex determination mechanisms, such as the loggerhead turtle (Caretta caretta), sex ratios may vary within a population and among populations. In the Mediterranean, juvenile sex ratios appear to not differ significantly from 1:1, although estimates for hatchling sex ratios are highly female biased. The immigration of males from the Atlantic has been suggested as a possible cause of such variation. Here, we present results of a multi-year investigation (2000–2011) on the sex ratios of loggerhead turtles foraging along the south Tyrrhenian coast, Western Mediterranean, with the aim of providing a better understanding of the potentially underlying forces that drive regional and age-dependent differences in sex ratios. Sex was determined through visual examination of the gonads in 271 dead turtles (curved carapace length range 29.5–89 cm). A fragment of the mitochondrial DNA control region was sequenced from 61 specimens to characterise the demographic composition of this foraging assemblage by applying a many-to-many mixed stock analysis approach. No significant association was found between sex ratios and years or size classes, although the largest size was male biased. Juvenile sex ratio was 1.56:1, which was different from an even sex ratio but still less female biased than hatchling sex ratios from Mediterranean beaches. Results of the mixed stock analysis indicate that juvenile sex ratios in the Mediterranean are largely unaffected by immigration of Atlantic individuals into the basin, as previously suggested. Continued long-term monitoring of juvenile sex ratios is necessary to detect biologically significant sex ratio shifts in the Mediterranean loggerhead turtle population.  相似文献   
496.
Stable carbon and nitrogen isotope analysis was used to examine the resources and position of macrobenthos in an estuarine seagrass food web in two sampling moments, during summer and winter. The contribution of each food source to the carbon requirements of consumers was estimated by a mixing model. The used carbon sources were largely seagrass associated, although seagrass tissues were utilized by only few species, and equally contributed to microphytobenthos and suspended particulate organic matter. Based on isotopic data, Lucinidae bivalves have an alternative trophic pathway via symbiosis with chemoautotrophic bacteria. Resource utilization inside and adjacent to seagrass beds did not differ significantly, implying that seagrass-associated inputs extend well beyond the borders of the vegetation patches.  相似文献   
497.
The common onion Allium cepa can be easily used in ecotoxicological bioassays to evaluate the bioavailability and adverse effects of pollutants and complex mixtures like waste, industrial effluent or coal-mining drainage that contain elevated levels of trace metals and polycyclic aromatic hydrocarbons (PAHs). In this study, onions were exposed for 7 days to individual metals (1?µg?mL?1), i.e., aluminium, copper, iron and manganese, or PAHs (1.5?ng?mL?1), i.e., benzo[a]antracene and benzo[a]pirene. Biological effects, measured as growth inhibition of roots and leaves, were integrated with analysis of bioaccumulation in roots, bulbs and leaves. Copper, iron and benzo[a]pirene caused a significant inhibition in root development of newly formed tissues, whereas only slight variations were caused by other chemicals; the number of new root filaments and the length of the leaves did not show significant variations, thus not representing sensitive parameters to evaluate adverse effects of pollutants in A. cepa. Chemicals bioaccumulation was always significant in roots, whereas levels in bulbs and leaves exhibited increased levels only for manganese, and a decrease for aluminium. The overall results confirmed the sensitivity of the bioassays with A. cepa, suggesting their utility for future applications to evaluate the adverse effects of complex mixtures containing metals or PAHs.  相似文献   
498.
A model predictive of the potential mutagenicity of organic compounds was devised by relating mutagenicity data obtained in the Ames reversion test to molecular structure parameters describing their hydrophobic, topological, steric and electronic properties. These included second order valence molecular connectivity index, parachor, molar refraction and polarizability of electrons. A classification rule was calculated, by means of discriminant analysis, using a training set of 117 compounds of various chemical classes. There was agreement between experimental data and theoretical expectations for the majority of compounds (70.9%), with homogeneous figures among the different chemical classes under scrutiny. An exception was represented by halogenated aliphatics with up to 3 C atoms, the mutagenicity of which was poorly predicted by the structural analysis model.  相似文献   
499.
Serratia marcescens, isolated from tannery effluents, was resistant to chromate (0.5 mM) under both aerobic and anaerobic conditions. A stable biofilm was developed, using activated carbon as a support. Extracellular precipitate suggests that insoluble chromium hydroxide was formed. The strain showed an enhanced cell growth in an aerobic culture medium, although under anaerobic conditions chromate reduction was carried out more efficiently. About 95% of chromate was reduced in 4 days.  相似文献   
500.
The North China Plain is one of the most important production areas for wheat and maize in China, and also has the densest agricultural population in China. How to use and develop the limited land resources reasonably, and improve and protect them, have become issues of major concern. This paper is based on sustainability theory, reviewing the fundamental principles of sustainability, and developing an index system with which to evaluate the sustainability status of land use. We also use this method to evaluate the land-use status of the North China Plain and to analyze current factors affecting sustainable land use in this area. In addition, we propose a specific method for evaluating sustainable land use.  相似文献   
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