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541.
There are numerous challenges that evaluators face when determining the success of urban climate resilience initiatives (e.g., how to attribute impacts to initiatives). Fortunately, a growing body of literature—much of it dealing with climate change adaptation—has emerged which can help address these challenges. This narrative review of academic and grey literature reviews various monitoring and evaluation methods that can assess the inputs, processes, outputs, outcomes, and impacts that result from climate resilience planning and action. Since there is no commonly accepted monitoring and evaluation approach, the literature stresses the importance of acknowledging the context in which resilience is being evaluated, in order to ensure that appropriate methods are chosen. This context includes the ways that the resilience framework and definition chosen for a project constrain and determine the monitoring and evaluation approaches which can be adopted. As a result of this, a blend of quantitative and qualitative approaches is often recommended, with sufficient evidence suggesting that qualitative approaches (e.g., outcome harvesting) are essential. Nuanced approaches to monitoring and evaluation give evaluators additional means of reporting progress, and of demonstrating success, which is especially important as cities begin to implement resilience initiatives in the coming years.  相似文献   
542.
The Oswaldo Cruz Foundation Campus (FIOCRUZ), in a suburban region of the city of Rio de Janeiro, was selected as a case study to assess the pollution released from vehicle and industrial facilities in Basin III, the most polluted area of the city. Concentrations of particulate matter (PM10) and trace metals in airborne particles were determined in an intensive field campaign. The samplings were performed every six days for 24 h periods, using a PM10 high volume sampler, from September 2004 to August 2005. PM10 mass concentrations were determined gravimetrically and the metals by ICP-OES. For PM10, the arithmetic mean for the period is 169 ± 42 μg m−3 which is 3.4 times the national recommended standard of 50 μg m−3. Additionally, 51% of the samplings exceeded the recommended 24 h limit of 150 μg m−3. Ca, Mg, Fe, Zn and Al were the metals that presented the higher concentrations. The correlation matrix gave two main clusters and three significant principal components (PC). Both PC1 and PC2 are associated to crustal, vehicular and industrial emissions while PC3 is mainly associated to geological material. Enrichment factors for Zn, Cu, Cd and Pb indicate that for these elements, anthropic sources prevail over natural inputs. PM10 levels showed a good correlation with hospital admissions for respiratory diseases in children and elderly people.  相似文献   
543.
Assessment of irrigation water quality. A proposal of a quality profile   总被引:1,自引:0,他引:1  
Water quality indices provide a simple and understandable tool for managers on the quality and possible uses for irrigation water, however an individual quality factor alone is not enough to evaluate the irrigation water quality because it could be restrictive and sometime it could give an unfavorable qualification. The aim of this paper was propose a quality profile of irrigation water using the preexisting water quality indices to be applied to arid and semi-arid regions. As a case studied, the water of the Del Molle River (Nogolí, San Luis, Argentina) was researched. Samples were collected during the period October 2005-May 2006. Conductivity, pH, total hardness, sulphate, nitrate, nitrite, alkalinity, chloride, sodium, potassium, TDS, DO and phosphate were analyzed. The irrigation water quality, according to Riverside Norm, belongs to C(2)-S(1) class, according to Wilcox Norm as excellent to good, according to Scott quality factor it is good and according to SAR < 10 and according to RCS it is recommendable. From the obtained data, it can be concluded that the water quality profile was good, so it is useful for normal irrigation agriculture.  相似文献   
544.
The fairness of PAYT systems: some guidelines for decision-makers   总被引:1,自引:0,他引:1  
Although the whole idea behind the PAYT approach is to develop a fairer system of waste charges than currently used, there still remains a number of issues that need to be considered when designing any given application of the PAYT principle, bearing in mind the variety of possible PAYT systems and the set of factors that influence their implementation. We assume that the perception of the system's fairness affects acceptance and thus participation, in the sense that the higher the perceived fairness the higher will be the acceptance of the system and, therefore, the higher the participation will be. Consequently, when it comes to analysing the acceptance of the implementation of a PAYT system or its effective functioning, waste management decision-makers should be interested in making sure that the system is perceived as fair in order to ensure a high participation rate. In addition, from a social point of view, decision-makers and politicians may be interested in the consequences of the operation of the system for other social values and in its impacts on particular groups of participants. This presentation examines the conditions for fairness and the considerations that should be taken into account so as to design a fair PAYT system in a specific municipality.  相似文献   
545.
Although human presence is one of the main characteristics of the Mediterranean identity since ancient times, a false dialectic between conservation and social-economic development has emerged in recent decades. On the one hand, an economic growth policy is taken as the paradigm of social-economic development; on the other hand, there is a multi-scale conservation policy, in which natural protected areas, as patches of preserved nature, are used as one of the main tools to deal with the challenge of sustainability. The Mediterranean Basin is the habitat of many unique species and one of the 25 main biodiversity hotspots in the world, and as a consequence a strong conservation policy has been used to protect environmental values. At the same time, Mediterranean countries are deeply involved in promoting strong economic growth policies, which are not always compatible with environmental ones. In this paper, Spain has been studied as one model of this situation. Due to political reasons, Spanish economic growth and conservationist policies were pursued together during the last 20 years. As a result, Spain owns one of the largest networks of natural protected areas in Western Europe, and at the same time it has experienced one of the strongest periods of economic growths in the European and Mediterranean context during the 1980s and 1990s. An historical series of resource use in five annual periods in the last 20 years of conservation policy, and the effects on the preservation of natural capital have been investigated by means of the eMergy (spelled with an 'm') synthesis approach, which was used to characterize the flow of environmental services supplied by ecosystems, but not in monetary terms. This study shows that Spain is becoming less self-sufficient and more inefficient in resource use, comprehensively measured in eMergy terms. A large part of Spain's economy depends on imported goods and services, and most economic activities are based on tourist services and associated construction, which promotes intensification in the urban use of the territory and more intense environmental impacts and resource use intensification of those countries supplying the raw materials. The consequence is a decoupling of the Spanish economy from local environmental services and the increase of Ecological footprint of Spain, measured by means of eMergy-based indicators. In spite of the increase in number, area and associated budget of the natural protected areas and other conservation measures, the general sustainability of the nation is decreasing.  相似文献   
546.
The quality of the sludge in Wastewater Treatment Plants (WWTPs) depends on the suitable colonization of the flocs by microorganisms. Due to the functional importance of these biological constituents, several biological or biological-related parameters have been commonly used for the control of depuration efficiency. According to national and international water regulation recommendations, interlaboratory studies have a great relevance to determine which parameters are more reliable for their extensive application in routine control. However, these studies are also very useful to demonstrate consistency in results from multiple laboratories and to develop reliable and reproducible methodologies which might be necessary for protocol validation and also for accreditation issues to meet regulatory environmental requirements. The main purpose of this work was to assess the results obtained in consecutive interlaboratory assays in order to determine the concordance degree in the application of biological parameters by participating laboratories. Following the international recommendations about these studies, a common working protocol was proposed. Statistical tests indicated that Sludge Index and several routine physical-chemical analyses [V30, Mixed Liquor Suspended Solids (MLSS), Mixed Liquor Volatile Solids (MLVS) and Sludge Volumetric Index (SVI)] show low variability and therefore are suitable tools for laboratory control. Shannon Index and Sludge Biotic Index also presented low variability although a more precise protocol would be necessary, in particular the methodology to count small flagellates. The abundance and identification of protist species showed low concordance among laboratories and three factors were responsible for the low reliability of data: population density, size and morphological distinguishable characters of the specimens.  相似文献   
547.
Users of automatic air pollution monitors are largely unaware of how certain parameters, like temperature, can affect readings. The present work examines the influence of temperature changes on chemiluminescence NO(x) measurements made with a Thermo Scientific 42i analyzer, a model widely used in air monitoring networks and air pollution studies. These changes are grouped into two categories according to European Standard EN 14211: (1) changes in the air surrounding the analyzers and (2) changes in the sampled air. First, the sensitivity tests described in Standard EN 14211 were performed to determine whether the analyzer performance was adapted to the requirements of the standard. The analyzer met the performance criteria of both tests; however, some differences were detected in readings with temperature changes even though the temperature compensator was on. Sample temperature changes were studied more deeply as they were the most critical (they cannot be controlled and differences of several tens of degrees can be present in a single day). Significant differences in readings were obtained when changing sample temperature; however, maximum deviations were around 3% for temperature ranges of 15°C. If other possible uncertainty contributions are controlled and temperature variations with respect to the calibration temperature are not higher than 15°C, the effect of temperature changes could be acceptable and no data correction should have to be applied.  相似文献   
548.
It is known that Brazil still has a privileged position of water quantity and quality, but water use has not proceeded in a responsible manner and often results in impairment of quality. This study aims to evaluate limnological parameters, parasites and bacteria, and concentrations of heavy metals (Cd, Pb, Cu, Cr, Mn, Hg, and Zn) in surface water of Ribeirão Preto Stream. The Ribeirão Preto Stream is located in urban areas under anthropogenic influence. The results showed that the levels of dissolved oxygen values were lower than those established by the National Environmental Council (CONAMA Resolution No 357/2005). The reading of electrical conductivity showed values typical of impacted environments. The parasitological analysis revealed the presence of nematode larvae. The bacteriological analysis showed higher values for total coliform and Escherichia coli than those set by the Brazilian National Environment Council (CONAMA). The heavy metals Cd, Pb, Cu, Cr, Mn, Hg, and Zn showed concentrations in accordance with the guidelines established by CONAMA. The results provide data on the quality of these waters and showed the necessity to protect the watercourse from point sources of contamination, recommending their continued monitoring.  相似文献   
549.
The European Water Framework Directive commits partner countries to evolve uniform protocols for monitoring the environmental condition of natural water bodies, crucially integrating biological and ecological criteria from the associated ecosystems. This has encouraged considerable research on the development of bioindicator-based systems of water quality monitoring. A critical step towards this end is providing evidence that the proposed bioindicator system adequately reflects the human pressures to which a specific water body is submitted. Here we investigate the utility of pulse-amplitude-modulated (PAM) fluorometry, a fast, non-destructive and increasingly popular bioindicator-based method, in assessing water quality based on the widespread Mediterranean seagrass Posidonia oceanica, an important constituent of submersed benthic vegetation. Specifically, we evaluated the ability of PAM to discriminate between sites along a pre-established gradient of anthropogenic pressures and the consistency and reliability of PAM parameters across spatial scales. Our results show that the maximum quantum yield (Fv/Fm), representing the structural photosynthetic efficiency of the plant, responds significantly to the degree of site-level anthropogenic pressure. However, Fv/Fm values in our study increased with increasing pressure, in striking contrast with other studies that report declines in Fv/Fm values with increasing stress. A potential explanation for this discrepancy is that our study sites were influenced by multiple diffuse stressors (characteristic of most coastal waters) that could potentially interact with each other to influence Fv/Fm values in often unpredictable ways. The photosynthetic variables calculated from rapid light curves (ETRmax, maximum electron transport rate; α, initial slope of the curve; I k, saturating irradiance), which represent an instant picture of the photosynthetic activity of the plant, were unable to clearly discriminate between sites subject to different anthropogenic pressures due to considerable small-scale variability. Taken together, these results suggest that even though PAM fluorometry may be a good candidate tool for monitoring water bodies in terms of costs and applicability, considerably more needs to be understood about how its parameters respond to real-world stressors, particularly when they act in concert with each other. With our present understanding of seagrass photosynthetic responses to anthropogenic stress, it would be ill advised to employ PAM as anything but a complementary tool to validate environmental stress derived with other, more robust methodologies.  相似文献   
550.
Water quality has degraded dramatically in the Chocancharava River (Río Cuarto, Córdoba, Argentina) due to point and non-point sources. This paper aims to assess spatial and temporal variations of physical and chemical parameters of the river. Six sampling sites and six sampling campaigns were developed. During the period 2007–2008, wet and dry seasons were included. A statistical analysis was carried out with 23 physical and chemical variables. Then, a new statistical analysis was carried out including the Riparian Corridors Quality Index and the physical and chemical variables (24 variables). Considering a multivariate system, analysis of variance, principal component analysis and cluster analysis were used. From the statistical analysis, the river was divided into two zones with different degrees of contamination. The most polluted zone is due to pollution inputs of urban, industrial and agricultural sources. This area showed a remarkable deterioration in water quality, mainly due to wastewater discharges. According to Riparian Quality, better results were found in sections of poor water quality, due to the fact that the river bank forest was less degraded downstream of the sewage discharge.  相似文献   
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