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21.
Yafa C Farmer JG Graham MC Bacon JR Barbante C Cairns WR Bindler R Renberg I Cheburkin A Emons H Handley MJ Norton SA Krachler M Shotyk W Li XD Martinez-Cortizas A Pulford ID MacIver V Schweyer J Steinnes E Sjøbakk TE Weiss D Dolgopolova A Kylander M 《Journal of environmental monitoring : JEM》2004,6(5):493-501
Given the increasing interest in using peat bogs as archives of atmospheric metal deposition, the lack of validated sample preparation methods and suitable certified reference materials has hindered not only the quality assurance of the generated analytical data but also the interpretation and comparison of peat core metal profiles from different laboratories in the international community. Reference materials play an important role in the evaluation of the accuracy of analytical results and are essential parts of good laboratory practice. An ombrotrophic peat bog reference material has been developed by 14 laboratories from nine countries in an inter-laboratory comparison between February and October 2002. The material has been characterised for both acid-extractable and total concentrations of a range of elements, including Al, As, Ca, Cd, Cr, Cu, Fe, Hg, Mg, Mn, Na, Ni, P, Pb, Ti, V and Zn. The steps involved in the production of the reference material (i.e. collection and preparation, homogeneity and stability studies, and certification) are described in detail. 相似文献
22.
Blain S Guillou J Tréguer P Woerther P Delauney L Follenfant E Gontier O Hamon M Leilde B Masson A Tartu C Vuillemin R 《Journal of environmental monitoring : JEM》2004,6(6):569-575
The MAREL Iroise data buoy provides physico-chemical measurements acquired in surface marine water in continuous and autonomous mode. The water is pumped 1.5 m from below the surface through a sampling pipe and flows through the measuring cell located in the floating structure. Technological innovations implemented inside the measuring cell atop the buoy allow a continuous cleaning of the sensor, while injection of chloride ions into the circuit prevents biological fouling. Specific sensors for temperature, salinity, oxygen and fluorescence investigated in this paper have been evaluated to guarantee measurement precision over a 3 month period. A bi-directional link under Internet TCP-IP protocols is used for data, alarms and remote-control transmissions with the land-based data centre. Herein, we present a 29 month record for 4 parameters measured using a MAREL buoy moored in a coastal environment (Iroise Sea, Brest, France). The accuracy of the data provided by the buoy is assessed by comparison with measurements of sea water weekly sampled at the same site as part of SOMLIT (Service d'Observation du Milieu LIToral), the French network for monitoring of the coastal environment. Some particular events (impact of intensive fresh water discharges, dynamics of a fast phytoplankton bloom) are also presented, demonstrating the worth of monitoring a highly variable environment with a high frequency continuous reliable system. 相似文献
23.
Llansó RJ Dauer DM Vølstad JH Scott LC 《Environmental monitoring and assessment》2003,81(1-3):163-174
The Chesapeake Bay benthic index of biotic integrity (B-IBI) was developed to assess benthic community health and environmental quality in Chesapeake Bay. The B-IBI provides Chesapeake Bay monitoring programs with a uniform tool with which to characterize bay-wide benthic community condition and assess the health of the Bay. A probability-based design permits unbiased annual estimates of areal degradation within the Chesapeake Bay and its tributaries with quantifiable precision. However, of greatest interest to managers is the identification of problem areas most in need of restoration. Here we apply the B-IBI to benthic data collected in the Bay since 1994 to assess benthic community degradation by Chesapeake Bay Program segment and water depth. We used a new B-IBI classification system that improves the reliability of the estimates of degradation. Estimates were produced for 67 Chesapeake Bay Program segments. Greatest degradation was found in areas that are known to experience hypoxia or show toxic contamination, such as the mesohaline portion of the Potomac River, the Patapsco River, and the Maryland mainstem. Logistic regression models revealed increased probability of degraded benthos with depth for the lower Potomac River, Patapsco River, Nanticoke River, lower York River, and the Maryland mainstem. Our assessment of degradation by segment and water depth provided greater resolution of relative condition than previously available, and helped define the extent of degradation in Chesapeake Bay. 相似文献
24.
Bioindicator organisms: Heavy metal pollution evaluation in the Ionian Sea (Mediterranean Sea—Italy)
Trace metal concentrations of mercury, cadmium, lead and chromium in Patella caerulea, and Mullus barbatus were investigated to provide information on pollution of Ionian Sea, since these metals have the highest toxic potential. High chromium levels (0.47–0.97 g g–1 ww) were registered in limpet samples collected from two station near the Gulf of Taranto, while elevated concentration of mercury (0.31–1.50 g g–1 ww) were found in mullet specimens from Sicily. The metal concentrations recorded at the clean stations may be considered as useful background levels to which to refer for comparison within the Mediterranean area. On the contrary, the high levels of chromium and mercury found respectively in the areas near the Gulf of Taranto and at Capo Passero being of concern in terms of environmental health need frequent monitoring. 相似文献
25.
Sommar J Feng X Gårdfeldt K Lindqvist O 《Journal of environmental monitoring : JEM》1999,1(5):435-439
Although it makes up only a few per cent. of total gaseous mercury (TGM) in the atmosphere, the fraction of oxidised (divalent) mercury plays a major role in the biogeochemical cycle of mercury due to its high affinity for water and surfaces. Quantitative knowledge of this fraction present in mixing ratios in the parts-per-10(15) (ppq) range is currently very scarce. This work is based on approximately 220 data for divalent gaseous mercury (DGM) collected during 1995-99 in ambient air. Over the course of the measurements, the sampling and analytical methods were modified and improved. This is described here in detail and includes transition from wet leaching and reduction procedures to thermo-reductive desorption, the use of annular as well as tubular denuders and adoption of an automated sampling system. The concentration of DGM exhibited a strong seasonal behaviour in contrast to atomic gaseous mercury, with low values in winter and maximum values in summer. The DGM/TGM ratios were frequently found to be below the detection limit (< or = 1%) and in the range 1-5%. A trend of diurnal DGM patterns was observed and implies photolytically induced sources. Scavenging of DGM during rain events was also noticed. 相似文献
26.
Clench-Aas J Bartonova A Grønskei KE Hagen LO Braathen OA Walker SE 《Journal of environmental monitoring : JEM》1999,1(4):341-347
This paper presents methodology and results of a dynamic individual air pollution exposure model (DINEX) that calculates the hourly exposure for each adult in a panel study. Each of over 260 participants, through the use of a diary, provided information used in the model to calculate his/her personal, individualised exposure. The participants filled out the diary daily, hour by hour, over two, two month periods. The exposure assessment model coupled the diary information and results of an indoor/outdoor measurement program, with the results of dispersion modelling on an hourly basis for an industrial area in Norway. The estimated air pollution concentrations from the dispersion model, based on continuous meteorological measurements, were calibrated with air pollutant concentrations measured continuously. 相似文献
27.
Sunesson AL Sundgren M Levin JO Eriksson K Carlson R 《Journal of environmental monitoring : JEM》1999,1(1):45-50
Tube type samplers with two different adsorbents, Chromosorb 106 and Tenax TA, were evaluated by laboratory experiments and field tests for simultaneous diffusive sampling of alpha-pinene, beta-pinene and delta 3-carene and subsequent thermal desorption-gas chromatographic analysis. No statistically significant effects of exposure time, concentrations of monoterpenes or relative humidity were found for samplers with Chromosorb 106 when running a factorial design, with the exception of the adsorption of delta 3-carene, for which some weak effects were noted. Samplers with Tenax TA were affected by the sampling time as well as the concentration for all terpenes, with a strong interaction effect between these two factors. The terpenes showed good storage stability on both adsorbents. No effect of back-diffusion was noted when using Chromosorb 106, while Tenax TA showed some back-diffusion effects. The uptake rates, in ml min-1, for the terpenes on Chromosorb 106 were 0.36 for alpha-pinene, 0.36 for beta-pinene and 0.40 for delta 3-carene. The corresponding average values on Tenax TA were 0.30 for alpha-pinene, 0.32 for beta-pinene and 0.38 for delta 3-carene. The field validation proved that diffusive sampling on Chromosorb 106 agreed well with pumped sampling on charcoal for stationary samples, while the personal samples indicated a discrepancy of 25% between Chromosorb 106 and charcoal samples. Tenax TA generally gave lower results than Chromosorb 106 in all field samples. Samplers packed with Chromosorb 106 could be used to monitor terpene levels in workplaces such as sawmills. The major advantages with this method are the sampling procedure, which is simple to perform compared to other techniques, the easily automated analysis procedure and the possibility to reuse the samplers. 相似文献
28.
Madbuli H. Noweir Ahmad A. Moreb Abdullah O. Bafail 《Environmental monitoring and assessment》1996,40(3):225-237
The present work was conducted to define the magnitude of the problem of heat exposure in Jeddah and the role of both the climatic and the industrial factors on the total heat load. Indoor heat exposure was studied in an industrial complex of 5 plants for cables' manufacturing. Outdoor heat exposure was studied in shaded and unshaded operations in Jeddah Islamic Port (JIP). The heat exposure parameters, including air temperature (Ta), wet bulb temperature (Tw), and globe temperature (Tg), as well as the wet bulb globe temperature (WBGT) heat stress index, the relative humidity and the air velocity, were assessed at representative locations. Results of the study indicated that:
An outline of a control strategy has been suggested, emphasizing evaporative engineering heat control, work and hygienic practices and auxiliary cooling clothing. 相似文献
(a) | the levels of heat exposure exceeded the TLV in mostly all the work areas where no air-conditioning is provided. |
(b) | the ambient heat is the factor contributing most to the heat load both in summer and in winter. |
(c) | the radiant heat from furnaces and hot metal rolling and milling adds more heat load to the work environment in specific operations. |
29.
Michael O. Angelidis Panagiotis G. Markantonatos Nikiforos Ch. Bacalis 《Environmental monitoring and assessment》1995,35(2):137-153
The impact of point (domestic and industrial effluents) and non-point (agricultural land runoff) pollution sources on the quality of the receiving waters of the Evrotas River (Laconia, Greece) was investigated during a monitoring study from August 1991 to August 1992. The part of the river which was located near the city of Sparta was seasonally influenced by the discharge of effluents from orange juice plants (operating during winter) and by the discharge of septage for the emptying of cesspools which are serving part of the city. The low dilution of incoming pollutants (septage) during the low water flow in summer lead to the decreasing self-purification capacity of the river and the development of septicity conditions in some of its parts. In the vicinity of intensively cultivated areas, the high concentrations of nitrogen and phosphorus which were detected in the river water during winter and spring may be partly attributed to the leaching of the applied fertilizers because of nirogen mobilization and soil erosion, following the season's precipitations. The protection of the Evrotas River water Quality must therefore include adequate treatment of the septage produced in the area, as well as the construction of wastewater treatment plants for the major industries of the area. The non-point pollution could be controlled by the restoration of the Evrotas riparian vegetation, together with a more rational use of fertilizers in the area. 相似文献
30.
Static bioassays were carried out using two aquatic snails (Pilia sp. and Lanistes sp.) as test organisms in soft natural dilution water, with waste drilling fluid as the test material, at 28±2°C. Comparison of results for the control and different concentrations of the waste drilling fluid were made by means of the F-statistic method. The waste drilling fluid was practically non-toxic to the two aquatic snails. 相似文献