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[en] Aims: Fecal indicator bacteria concentrations were evaluated in Havana Bay. Methods: Concentrations of traditional fecal indicator bacteria were calculated between April 2010 and February 2011, by MPN methods. Concentrations of thermo tolerant coliform (CTT), Escherichia coli, fecal streptococci (EF), intestinal enterococci (ENT) in seawater, and Clostridium perfringens in sediment surface, were determined. Results: CTT and E. coli levels were far above Cuban water quality standard for indirect contact with water, showing the negative influence of sewage and rivers on the bay. The EF and ENT were measured during sewage spills at the discharge site and they were suitable indicators of fecal contamination, but these indicators didn't show the same behavior in other selected sites. This result comes from its well-known inactivation by solar light in tropical zones and the presumable presence of humid acids in the waters of the bay. Conclusion: Fecal indicator bacteria and its statistical relationships reflect recent and chronic fecal contamination at the bay and near shores.
[en] One of the essential aims of the CALDEX project is the comparative evaluation of the conventional tank calibration procedure using an incremental addition of liquor and of the calibration with a continuous liquid feed. The three calibration exercises performed with water in continuous mode have been evaluated. Estimates of volume determination uncertainty are given for all manometers which can be compared with the evaluations from other calibration procedures
[en] A preliminary Multimetric Macroinvertebrate Index for Rivers of the Department of Boyaca (IMARBO) was developed to assess the ecological status of five rivers and streams in the upper and middle basins of the Chicamocha River. Physicochemical and biological parameters of the aquatic macroinvertebrate community were characterized in three reference reaches and nine locations with different degrees of alteration due to deforestation, modification of habitats and domestic and industrial wastes. The environmental stress gradient was established by principal component analysis (PCA) and bivariate correlations. 21 metrics from the macroinvertebrate community were calculated, of which six were selected for the IMARBO conformation through correlations with the environmental gradient. For the selected metrics, its Discriminative Efficiency (DE) was calculated between reference and disturbed stations. The index included Ephemeroptera, Plecoptera and Trichoptera (EPT) family richness, % of Ephemeroptera richness,% of Plecoptera richness, total abundance of individuals, % of Filters abundance and the BMWP/Col index. With the percentiles of the metrics in the reference reaches, the biotic integrity and ecological quality scales of the rivers studied were developed, which were preliminarily validated with an independent database in a basin close to the one studied. The proposed index constitutes a preliminary approximation that will require future verifications through a greater number of data. However, the results made it possible to clearly differentiate the least polluted rivers with a high biotic integrity (Gameza and Mongui) from those that are greatly deteriorated and whose macroinvertebrate communities have very low biotic integrity (Chicamocha, Malsitio, Nobsa). In this way, the IMARBO index could become a useful tool for the environmental management of the rivers in the region.
[en] The last international features proposed by the Organization for Economic Cooperation Development (OECD) and United Nations (UN) are analyzed in the use of the environmental indicators, in typology, selection criteria, and models, for organizing the information for management, environmental performance, and decision making. The advantages and disadvantages of each model are analyzed, as well as their environmental index characteristics. The analyzed models are Pressure - State - Response (PSR) and its conceptual developments: Driving Force - State Response (DSR), Driving Force - Pressure - State - Impact - Response (DPSIR), Model- Flow-Quality (MFQ), Pressure - State - Impact - Effect - Response (PSIER), and, finally, Pressure-State - Impact - Effect - Response - Management (PSIERM). The use of one or another model will depend on the quality of the available information, as well as on the proposed objectives
[en] The use of biological indicators is widespread in environmental monitoring, although it has long been recognised that each bioindicator is generally associated with a range of potential limitations and shortcomings. To circumvent this problem, this study adopted the complementary use of bioindicators representing different trophic levels and providing different type of information, in an innovative approach to integrate knowledge and to estimate the overall health state of ecosystems. The approach is illustrated using mercury contamination in primary producers (mosses), primary consumers (domestic pigeons and red-legged partridges) and top predators (Bonelli's eagles) in southern Portugal. Indicator kriging geostatistics was used to identify the areas where mercury concentration was higher than the median for each species, and to produce an index that combines mercury contamination across trophic levels. Spatial patterns of mercury contamination were consistent across species. The combined index provided a new level of information useful in incorporating measures of overall environmental contamination into pollution studies. - Mercury levels in bioindicators at three trophic levels were combined using geostatistics to build an integrated environmental contamination index.
[en] The analysis of 90 surficial sediments from three docks of the Naples Harbour (Levante, Granili, and Diaz) permits to compare the distribution modes of heavy metals with grain sizes, total organic carbon content (TOC) and distribution patterns of benthic foraminifera. Foraminiferal density and species richness decrease with the increasing toxic elements concentrations from the Levante to the Diaz dock. Median concentrations of Ni, Pb, Zn, and Hg (medians of 21.43 mg/kg, 270.24 mg/kg, 489.65 mg/kg, and 1.18 mg/kg, respectively) were reported for the Diaz dock where foraminifera are absent, thus suggesting a possible impact of toxic elements on the benthic ecosystem balance. Compared to the unpolluted marine sediments of the Granili dock, the Levante area shows higher heavy metals levels and a quasi-oligotypic benthic assemblage. This is dominated by the tolerant species Ammonia tepida that may be used as bio-indicator of pollution of anthropised marine sediments. - Benthic foraminiferal density and species distribution may be used as pollution indicators
[en] Systems for remotely detecting the presence or absence of a fluid in a vessel comprising a probe with two electrodes, the electric resistance between them depending on the condition to be detected. The electrodes, which are insulated with respect to the earth, are connected through a first pair of leads to the terminals of a current generator and, through a second pair of leads, to the terminals of a current and or voltage variation detection circuit. It can be used for monitoring the state of the core of a nuclear reactor pond, or of its protective casing. In the event of an operational incident occurring in the reactor, the water likely to be present between the probe electrodes is a highly deionized water, the presence of which could not be revealed by conventional probes. The probe can be made without difficulty from materials withstanding nuclear radiations
[fr]Dispositif pour detecter a distance la presence ou l'absence d'un fluide dans une enceinte, comprenant une sonde a deux electrodes, la resistance electrique entre ces dernieres etant fonction de la condition a detecter. Les electrodes, isolees par rapport a la masse, sont connectees par l'intermediaire d'un premier couple de conducteurs aux bornes d'un generateur de courant, et par l'intermediaire d'un second couple de conducteurs aux bornes d'un circuit de detection d'une variation de courant et/ou de tension. On peut l'utiliser pour controler l'etat du coeur de la piscine d'un reacteur nucleaire, ou de son enveloppe de protection. En cas d'incident de fonctionnement du reacteur, l'eau susceptible de se trouver entre les electrodes de la sonde est une eau fortement desionisee, dont la presence serait indecelable par des sondes classiques. La sonde peut etre facilement realisee en materiaux resistant aux radiations nucleaires
[en] This article undertakes a review of alternative measures and indicators of energy poverty targeted to specific audiences and for particular purposes. At the national and international scales there have been some efforts for constructing measures of energy poverty. However, much more needs to be done to develop an internationally consistent measurement framework and to put in place data collection systems that will enable regular reporting. At the programme and project level, indicator systems by necessity need to be designed for specific purposes. Nevertheless, the article proposes that in many instances it is desirable to widen the scope of metrics used for designing and evaluating policies and programmes. In the past, monitoring and evaluation indicators have focused largely on outputs, service delivery or dissemination. Central to the recommendations laid out in the paper is the call for widening the focus of evaluation and necessity to design indicators that adequately assess the needs of beneficiaries and describe the living conditions of families and communities, who are targeted by such programmes and initiatives. - Highlights: ► Consistent measurement frameworks and regular data collection systems on energy poverty are needed. ► Metrics used for designing and evaluating energy access programmes should be widened. ► Indicators that adequately assess needs and describe living conditions of targeted beneficiaries are required.