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61.
The solar phototransformation of furosemide has been investigated in aqueous media. Irradiation of the drug in distilled water, in water and humic acids or nitrate ions, and in sewage sludge water affords a new dehalogenated dimer. The formation of the dimer has been explained by the formation of a cation radical intermediate. The low-measured environmental concentration of furosemide with respect to predicted environmental concentration in the Po and Lambro Rivers could be justified by its phototransformation.  相似文献   
62.
The paper reports a methodology adopted to face problems related to quality assurance in soil sampling. The SOILSAMP project, funded by the Environmental Protection Agency of Italy (APAT), is aimed at (i) establishing protocols for soil sampling in different environments; (ii) assessing uncertainties associated with different soil sampling methods in order to select the "fit-for-purpose" method; (iii) qualifying, in term of trace elements spatial variability, a reference site for national and international inter-comparison exercises. Preliminary results and considerations are illustrated.  相似文献   
63.
Anguilla anguilla L. were exposed to 0, 0.1, 0.3, 0.9 and 2.7 microM abietic (AA), dehydroabietic (DHAA) acids and retene (Re) during 8, 16, 24 and 72 h. The eels plasma cortisol, glucose and lactate were measured. A significant decrease in plasma cortisol was observed at 72 h exposure to 0.9 and 2.7 microM Re. DHAA (0.1 microM) significantly decreased plasma cortisol in eels after 8 and 24 h exposure. However, a significant plasma cortisol increase was found after 16 h, 2.7 microM AA exposure and after 24 h exposure to 0.1 microM and 2.7 microM AA. Furthermore, 72 h exposure to 0.9 microM AA also induced a plasma cortisol increase. A general rise in plasma glucose was detected after all exposure periods to Re. The plasma lactate also increased after 72 h exposure to 2.7 microM AA and after 8 h exposure to 0.1 microM DHAA.  相似文献   
64.
The aim of the study was to determine whether there are signs of adaptation of soil fauna to a gradient of heavy metal contamination. Earthworms Aporrectodea caliginosa, Lumbricus terrestris and Eisenia fetida were collected during the spring and summer of 2000 and 2001 from meadow sites situated between 2 and 32 km from the Bukowno-Olkusz complex of zinc-lead ore mines and smelters. The heavy metal content in the soil near smelters reaches 10,500 mg/kg (d.w.) for Zn, 2600 mg/kg for Pb and 81.9 mg/kg for Cd. The sites differ with respect to species composition of earthworm community, with A. caliginosa being dominant. Complete data was obtained only for A. caliginosa, since other species were not abundant at all investigated sites during the whole period of investigation. The body burdens of Zn, Pb, Cd and Cu in A. caliginosa reached 1500, 100, 220 and 10 microg/g, respectively, in the vicinity of the smelter (2-4 km), and decreased to 400, 2, 36 and 6 microg/g at the most distant site (32 km). Cadmium and lead content was significantly elevated in the whole body of L. terrestris collected at the site 2.5 km distant from the smelters when compared to more distant sites, while in E. fetida only the body burden of cadmium was elevated at the nearest site compared to the next site of transect. Activities of glutathione peroxidase (GPX; EC 1.11.1.9) against hydrogen peroxide (H2O2) or cumene hydroperoxide (cumOOH), glutathione reductase (GR; EC 1.6.4.2), glutathione S-transferase (GST; EC 2.5.1.18) and catalase (CAT; EC 1.11.1.6) were assayed in postmitochondrial supernatant obtained from whole body homogenates. Seasonal and annual variations of enzyme activity were reflected by higher GPX activity in the late summer of 2001 in comparison with the spring and summer of 2000. This may reflect severe drought in the spring and summer of 2000. The activity of both GPX isozymes, GR and GST in A. caliginosa and L. terrestris increased with increasing distance from the smelters and reached maximum at sites III and IV (4 and 8 km from the smelters, respectively) and then it decreased in the animals from site V (32 km). These may be the effects of antagonism between the enzyme inducing and enzyme inhibiting action of smelter emissions, a phenomenon known as a hormetic effect. It is postulated here that this effect is of diagnostic value for metal pollution biomonitoring.  相似文献   
65.
The aim of the study was to compare radon concentrations in neighbouring hospital buildings which were constructed in different years during the period 1963-2000 and are located in areas with similar radon potential. The value of arithmetic mean (AM) radon concentration in soil gas amounted to 14,464 Bq m(-3). In a hospital built 40 years ago, the AM radon concentration in the cellar was 38.4+/-36.7 Bq m(-3) and on higher levels it was 17.1+/-10.3 Bq m(-3). In a hospital built 16 years ago, these values equaled 45.5+/-47.2 Bq m(-3) and 20.4+/-12.5 Bq m(-3), respectively. In the newest hospital, built three years ago, radon concentration (AM) in a cellar was 32.3+/-27.4 Bq m(-3) and the respective value on higher levels amounted to 20.4+/-12.6 Bq m(-3). When comparing radon concentrations in the cellars, no statistically significant differences were found. Similarly, no statistically significant differences were observed between radon concentrations measured on higher levels in investigated hospital buildings.  相似文献   
66.
During the Fifth Framework Programme (FP5) of the European Commission--according to an institutional programme in support to the policy of the European Commission for the implementation of Art. 35 and 36 of the Euratom Treaty as well as in the framework of the OSPAR Convention for the protection of marine environment of the north-east Atlantic--at the Institute for Transuranium Elements (ITU--General Directorate Joint Research Centre--European Commission), a reference laboratory for the measurement of radioactivity in the environment (MaRE laboratory) has been set up. In this paper, the principles and philosophy in order to improve the quality and reliability of analytical data for the measurement and monitoring of radioactivity in the environment under a quality assurance (QA) programme are presented. Examples of how a QA programme at the MaRE laboratory is developed and applied are given. Internal and external quality control (QC) programmes are also discussed.  相似文献   
67.
Community-based coastal resource management has been widely applied within the Philippines. However, small-scale community-based reserves are often inefficient owing to management inadequacies arising because of a lack of local support or enforcement or poor design. Because there are many potential pitfalls during the establishment of even small community-based reserves, it is important for coastal managers, communities, and facilitating institutions to have access to a summary of the key factors for success. Reviewing relevant literature, we present a framework of lessons learned during the establishment of protected areas, mainly in the Philippines. The framework contains summary guidance on the importance of (1) an island location, (2) small community population size, (3) minimal effect of land-based development, (4) application of a bottom-up approach, (5) an external facilitating institution, (6) acquisition of title, (7) use of a scientific information database, (8) stakeholder involvement, (9) the establishment of legislation, (10) community empowerment, (11) alternative livelihood schemes, (12) surveillance, (13) tangible management results, (14) continued involvement of external groups after reserve establishment, and (15) small-scale project expansion.These framework components guided the establishment of a community-based protected area at Danjugan Island, Negros Occidental, Philippines. This case study showed that the framework was a useful guide that led to establishing and implementing a community-based marine reserve. Evaluation of the reserve using standard criteria developed for the Philippines shows that the Danjugan Island protected area can be considered successful and sustainable. At Danjugan Island, all of the lessons synthesized in the framework were important and should be considered elsewhere, even for relatively small projects. As shown in previous projects in the Philippines, local involvement and stewardship of the protected area appeared particularly important for its successful implementation. The involvement of external organizations also seemed to have a key role in the success of the Danjugan Island project by guiding local decision-makers in the sociobiological principles of establishing protected areas. However, the relative importance of each component of the framework will vary between coastal management initiatives both within the Philippines and across the wider Asian region.Published on line  相似文献   
68.
This work presents an analysis of a stirred anaerobic sequencing discontinuous reactor with different substrate feeding strategies resulting in batch, fed-batch/batch and fed-batch operating modes. The reactor, containing granulated biomass, was fed with approximately 2.0L of synthetic domestic wastewater with Chemical Oxygen Demand of nearly 500 mg/L per cycle and operated at 30 degrees C and 50 rpm. Three feeding strategies with a total cycle time of 6 h, including 30-min settling, were adopted: batch mode with a fill cycle of 6 min, a fed-batch/batch mode with fill cycles of 60, 120 and 240 min and fed-batch mode with a fill cycle of 320 min. The system attained average non-filtered and filtered substrate removal efficiency of 78 and 84%, respectively, for all operating conditions, presenting good stability, solid retention and no granule break-up. A first order kinetic model with a residual organic matter concentration was proposed to analyze the influence of the feeding strategy on the performance during a cycle and bicarbonate alkalinity and total volatile acids concentration profiles were also quantified in order to verify the transient stability behavior.  相似文献   
69.
Traditional ecological knowledge (TEK) and the information and insights it offers to natural resource research and management have been given much attention in recent years. On the practical question of how TEK is accessed and used together with scientific knowledge, most work to date has examined documentation and methods of recording and disseminating information. Relatively little has been done regarding exchanges between scientific and traditional knowledge. This paper examines three workshop settings in which such exchanges were intended outcomes. The Barrow Symposium on Sea Ice, the Exxon Valdez Oil Spill Restoration Program Synthesis/Information Workshops, and the Alaska Beluga Whale Committee illuminate certain features of the preparation, format, and context of workshops or series of workshops and their eventual outcomes and influence. The examples show the importance of long-term relationships among participants and thorough preparation before the actual workshop. Further research should look more systematically at the factors that influence the success of a given workshop and the various ways in which participants perceive success.  相似文献   
70.
Isidorov V  Jdanova M 《Chemosphere》2002,48(9):975-979
Qualitative composition of volatile emissions of litter of five species of deciduous trees was investigated by GC-MS. The list of identified substances contains more than 70 organic compounds of various classes. It was established that the composition of components emitted by the litter into the gas phase greatly differs from that of essential oils extracted by hydrodistillation from turned leaves collected from trees during fall. It is suggested that most compounds found in litter emissions are products of vital activity of microorganisms decomposing it. The reported data indicate that after the vegetative period is over the decomposition processes of litter are important seasonal sources of reactive organic compounds under the forest canopy.  相似文献   
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