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931.
Application and sensitivity testing of a eutrophication assessment method on coastal systems in the United States and European Union 总被引:5,自引:0,他引:5
The Assessment of Estuarine Trophic Status (ASSETS) screening model has been extended to allow its application to both estuarine and coastal systems. The model, which combines elements of pressure, state and response, was tested on four systems: Maryland Coastal Bays and Long Island Sound in the United States and The Firth of Clyde (Scotland) and Tagus Estuary (Portugal) in the European Union. The overall scores were: Maryland Coastal Bays: Bad; Firth of Clyde: Poor; Tagus Estuary: Good. Long Island Sound was modelled along a timeline, using 1991 data (score: Bad) and 2002 data (score: Moderate). The improvement registered for Long Island Sound is a consequence of the reduction in nutrient loading, and the ASSETS score changed accordingly. The two main areas where developments are needed are (a) In the definition of type-specific ranges for eutrophication parameters, due to the recognition that natural or pristine conditions may vary widely, and the use of a uniform set of thresholds artificially penalizes some systems and potentially leads to misclassification; (b) In the definition and quantification of measures which will result in an improved state through a change in pressures, as well as in the definition of appropriate metrics through which response may be assessed. One possibility is the use of detailed research models where different response scenarios potentially produce changes in pressure and state. These outputs may be used to drive screening models and analyze the suitability of candidate metrics for evaluating management options. 相似文献
932.
The development of environmental performance policy indicators for public services, and in particular for the defence sector, is an emerging issue. Despite a number of recent initiatives there has been little work done in this area, since the other sectors usually focused on are agriculture, transport, industry, tourism and energy. This type of tool can be an important component for environmental performance evaluation at policy level, when integrated in the general performance assessment system of public missions and activities. The main objective of this research was to develop environmental performance policy indicators for the public sector, specifically applied to the defence sector. Previous research included an assessment of the environmental profile, through the evaluation of how environmental management practices have been adopted in this sector and an assessment of environmental aspects and impacts. This paper builds upon that previous research, developing an indicator framework--SEPI--supported by the selection and construction of environmental performance indicators. Another aim is to discuss how the current environmental indicator framework can be integrated into overall performance management. The Portuguese defence sector is presented and the usefulness of this methodology demonstrated. Feasibility and relevancy criteria are applied to evaluate the set of indicators proposed, allowing indicators to be scored and indicators for the policy level to be obtained. 相似文献
933.
Przemys?aw?Siemion Jolanta?Jab?ońska Janusz?Kapu?niak Jacek?J.?Kozio?Email author 《Journal of Polymers and the Environment》2004,12(4):247-255
Reaction of granular potato starch with urea and biuret resulted in the formation of products, which were soluble neither in cold nor boiling water. The net reaction was a monosubstitution of the hydrogen atom in one hydroxyl group in each D-glucose unit of starch with the either CO–NH2 or CO–NH–CO–NH2 moiety, respectively. Properties of the products, particularly these with urea, depended on the mode of reaction. Reactions were carried out in the microwave oven as well as with convection heating. The products retained the granular form of starch but a vast majority of granules were damaged. -Amylolysis of those materials revealed that their susceptibility to the enzyme increasing in the order: starch-amylolysis with simultaneous insolubility in water make these products suitable as ruminant fodder and, eventually, biodegradable material. 相似文献
934.
Polychlorinated biphenyls (PCBs) are a mixture of 209 possible congeners with different chlorine substitutions and they are potentially hazardous compounds in the environment for human beings. The high lipophilicity and the resistance to biodegradation of PCBs allow the bioaccumulation of these chemicals in the fatty tissues of organisms. The objective of this study was to determine the levels of PCBs in the adipose tissue of women living in Ankara, Turkey. For this purpose, levels of seven major persistent PCB congeners (IUPAC Numbers: 28, 52, 101, 118, 138, 153, 180) were measured in 29 primiparous mothers' adipose tissue samples by gas chromatography with electron capture detection (GC-ECD). PCB IUPAC numbers 138, 153 and 180 were the most abundant congeners, each accounting for > 20% of the total PCB content of adipose tissue. PCB 153 was the dominant congener in all the samples (141.7 +/- 132.3 ng/g lipid wt. basis). The results are compared with the similar studies from other countries. The concentrations of PCB 28, PCB 52 and PCB 101 were found to be higher than those found in industrialized countries. This study is important in terms of being the first study of determination of PCB levels in adipose tissue samples in Turkey. 相似文献
935.
Sandra?BrucetEmail author Dani?Boix Rocìo?López-Flores Anna?Badosa Xavier?D.?Quintana 《Marine Biology》2005,148(1):131-139
Changes in amino acid composition (AAC) during ontogeny of some planktonic crustacean species commonly found in fresh and brackish coastal waters were compared. For these comparisons two calanoid copepods (Eurytemora velox and Calanipeda aquae-dulcis), two cyclopoid copepods (Diacyclops bicuspidatus odessanus and Acanthocyclops robustus) and two Daphnia (Daphnia pulicaria and Daphnia magna) species were selected. A discriminant analysis was performed to determine whether there were significant differences between the AAC of the different stages of each species. Results show gradual changes in AAC during ontogeny of the copepod species. Calanoids showed the greatest differences in AAC between stages, followed by cyclopoids. Gradual changes in AAC were due to the increase in some amino acids such as alanine, valine, glutamic acid, glycine, arginine, proline and tyrosine from nauplii to adults. The latter showed a remarkable increase in all copepod species. In contrast, Daphnia species showed a relatively constant AAC during development, with only minor changes being detected, and not related with ontogeny. Differences in the physico-chemical variables of the lagoons do not seem to be the cause of copepod ontogenic changes in AAC. Data suggest that AAC differences found between stages of copepod species could indicate a gradual change in diet during the life cycle of these copepods. 相似文献
936.
Paranhos Gazineu MH de Araújo AA Brandão YB Hazin CA de O Godoy JM 《Journal of environmental radioactivity》2005,81(1):47-54
Scales and sludge generated during oil extraction and production can contain uranium, thorium, radium and other natural radionuclides, which can cause exposure of maintenance personnel. This work shows how the oil content can influence the results of measurements of radionuclide concentration in scale and sludge. Samples were taken from a PETROBRAS unit in Northeast Brazil. They were collected directly from the inner surface of water pipes or from barrels stored in the waste storage area of the E&P unit. The oil was separated from the solids with a Soxhlet extractor by using aguarras at 90+/-5 degrees C as solvent. Concentrations of 226Ra and 228Ra in the samples were determined before and after oil extraction by using an HPGe gamma spectrometric system. The results showed an increase in the radionuclide concentration in the solid (dry) phase, indicating that the above radionuclides concentrate mostly in the solid material. 相似文献
937.
Gomes JF 《Journal of the Air & Waste Management Association (1995)》2005,55(4):497-501
More than 13 years after publication of the first air quality laws in Portugal and more than 10 years after the publication of the respective emission limits, it seems appropriate to analyze the degree of compliance by the Portuguese manufacturing industry. Using the data from emission measurements made regularly by the Instituto de Soldadura e Qualidade, the only officially accredited laboratory according to standard ISO 17025, I analyzed a set of approximately 400 sources in terms of compliance with the emission limits regarding total suspended particulates, sulfur dioxide, nitrogen oxides, and volatile organic compounds. I evaluated compliance through a nondimensional parameter and plotted it versus the emission flow rate to derive conclusions: the results indicate that emission limits are generally met regarding sulfur dioxide and nitrogen oxides but not for the other pollutants considered in this study. However, noncompliance occurs mainly for very low emission flow rates, which suggests some alterations in the emission limits, which are being revised at the moment. These alterations will include the exemption of measurements in minor sources. 相似文献
938.
This article intends to shed a light on air quality in Turkey and compare air pollutant emissions on a national scale with that of the European countries. In order to estimate the quantities of Turkish emissions in the past and their future predictions, a national emission inventory was prepared with respect to five major pollutants consisting of particulate matter(PM), SOx, NOx, non-methane volatile organic compounds, and CO with 5-year intervals between 1985 and 2005. The results suggest that Turkey is a rather large emission source at the European scale, although emission indicators on unit area and per capita were shown to be somewhat smaller in magnitude. Levels of air pollution in some of the big cities in Turkey were also evaluated from available national monitoring data. These evaluations for the urban air qualities covered SO2 and PM parameters between 1986 and 1996, and results were compared with the present Turkish air quality limits, their probable revisions, WHO (Europe) guidelines and related EC directives. Results showed that the air quality limits were not met, especially during the winter periods in Turkish cities. Urban air pollutants characterizing the air in Turkish cities other than SO2 and PM, however, could not have been evaluated as these pollutants were not systematically monitored in these cities. 相似文献
939.
This note describes a technique for cutting undisturbed brittleblock samples into smaller specimens for further geotechnical testing. This technique revealed very useful in dealing with collapsible soils, where the sampling is recommended to be donewith block soil samples. A further use of this technique as an efficient way for sampling collapsible soils is proposed. 相似文献
940.
In this work, mercury speciation in phosphorus powder matrices and soda lime glass waste from new and spent fluorescent lamp wastes has been studied by thermo-desorption/atomic absorption spectrometry (TDAAS), X-ray diffraction (XRD), cold vapor-atomic absorption (CV-AAS) and atomic emission spectrometry/inductively coupled plasma (ICP/AES). TDAAS results show the presence of oxidized forms of mercury, i.e., Hg(1+) and Hg(2+), especially in wastes with high mercury concentration. Such forms are mobile, and therefore represent a potential hazard waste material. Glass TD profiles of spent fluorescent lamps suggested the presence of mercury strongly linked to the matrix, which desorbs only at high temperatures. 相似文献