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981.
Ambient particles vary greatly in their ability to affect visibility, climate and human health. The fine fraction of aerosol
is responsible for greater and wider effects on human health; thus, investigation of this fraction is very important. Continuous
measurements of PM2.5 (particulate matter below 2.5 μm in size) concentrations at the Preila monitoring station started in
2003. During a period of 2 years, the episodes of high daily and semi-hourly concentrations of PM2.5 were measured. These
episodes did not depend on the season or time of day. The substantial role of long-range transport of pollutants to these
increases in concentration was shown using chemical and statistical analysis. It was found that most of the severe episodes
occurred when air masses came from a specific site besides it was established that air masses of different origin were characterized
by different mixing layer depth. Lower mixing depth was observed in air masses characterized by higher observed concentrations
at the measuring site and vice versa. PM2.5 concentrations showed diurnal and seasonal variations whose pattern reflected
the regional origin of the aerosol. The regional pollution level was evaluated by the statistical analysis of PM2.5 concentrations.
The background annual average of PM2.5 mass concentration for the eastern coast of the Baltic Sea was 15.1 ± 0.8 μg m−3. 相似文献
982.
Nitrogen (N) pollution is a growing concern in forests of the greater Sierra Nevada, which lie downwind of the highly populated
and agricultural Central Valley. Nitrogen content of Letharia vulpina tissue was analyzed from 38 sites using total Kjeldahl analysis to provide a preliminary assessment of N deposition patterns.
Collections were co-located with plots where epiphytic macrolichen communities are used for estimating ammonia (NH3) deposition. Tissue N ranged from 0.6% to 2.11% with the highest values occurring in the southwestern Sierra Nevada (range:
1.38 to 2.11). Tissue N at 17 plots was elevated, as defined by a threshold concentration of 1.03%. Stepwise regression was
used to determine the best predictors of tissue N from among a variety of environmental variables. The best model consisted
only of longitude (r
2 = 0.64), which was reflected in the geographic distribution of tissue values: the southwestern Sierra Nevada, the high Sierras
near the Tahoe Basin, and the Modoc Plateau, are three apparent N hotspots arranged along the tilted north–south axis of the
study area. Withholding longitude and latitude, the best regression model suggested that NH3 estimates and annual number of wetdays interactively affect N accumulation (r
2 = 0.61; % N ∼ NH3 + wetdays + (NH3 × wetdays)). We did not expect perfect correspondence between tissue values and NH3 estimates since other N pollutants also accumulate in the lichen thallus. Additionally, other factors potentially affecting
N content, such as growth rate and leaching, were not given full account. 相似文献
983.
The air temperature distributions in August (summer) and December (winter) were measured in an approximately 15 × 15-km urban
area in Hyogo Prefecture, Japan, in order to study the spatial distribution of the air temperature and to propose effective
measures against the heat island phenomenon. The air temperature was measured mainly by using thermometer shelters installed
in an elementary school and a junior high school. The characteristic air temperature distribution depended on the season.
The air temperature was higher inland than in the coastal region in August but was higher in the coastal region in December.
The air temperature index indicated that the area where higher air temperatures would most likely appear was 5 to 10 km inland
from the coast in August and around the coast in December. The seasonal air temperature distribution was presumably due to
the strength of solar radiation and anthropogenic exhaust heat. 相似文献
984.
Yazvenko SB McDonald TL Blokhin SA Johnson SR Melton HR Newcomer MW Nielson R Wainwright PW 《Environmental monitoring and assessment》2007,134(1-3):93-106
Exxon Neftegas Limited, as operator of the Sakhalin-1 consortium, is developing oil and gas reserves on the continental shelf
off northeast Sakhalin Island, Russia. DalMorNefteGeofizika (DMNG) on behalf of the Sakhalin-1 consortium conducted a 3-D
seismic survey of the Odoptu license area during 17 August–9 September 2001. A portion of the primary feeding area of the
endangered western gray whale (Eschrichtius robustus) is located in the vicinity of the seismic survey. This paper presents data to assess whether western gray whale bottom feeding
activity, as indicated by visible mud plumes, was affected by seismic operations. The mitigation and monitoring program associated
with the seismic survey included aerial surveys during 19 July–19 November 2001. These aerial surveys documented the local
and regional distribution, abundance, and bottom feeding activity of western gray whales. Data on gray whale feeding activity
before, during and after the seismic survey were collected, with the whales assumed to be feeding on the benthos if mud plumes
were observed on the surface. The data were used to assess the influence of seismic survey and other factors (including environmental)
on feeding activity of western gray whales. A stepwise multiple regression analysis failed to find a statistically significant
effect (α = 0.05) of the seismic survey on frequency of occurrence of mud plumes of western gray whales used as a proxy to evaluate
bottom feeding activity in Piltun feeding area. The regression indicated that transect number (a proxy for water depth, related
to distance from shore) and swell height (a proxy for sea state) were the only variables that had a significant effect on
frequency of whale mud plumes. It is concluded that the 2001 seismic survey had no measurable effect (α = 0.05) on bottom feeding activity of western gray whales off Sakhalin Island.
M.W. Newcomer, deceased 相似文献
985.
Objective This study was done to estimate whether heavy metals in the air may affect endometrial chemical composition.
Materials and Methods A total of 30 albino Wistar rats were employed and randomly divided into three groups. The rats of Group 1 and 2 were acutely
and sub-chronically exposed to the gas form of heavy metals, respectively. Group 3 was used as a control group. Endometrial
tissue worth of heavy metals of the groups was measured in through using scanning electron microscope.
Results A statistically no significant difference was found for endometrial chemical composition of all of the heavy metals (chrome,
manganese, iron, cobalt, nickel, zinc and lead) between group 1 and 2 (p > 0.05). On the other hand, there was statistically significant difference for all of the heavy metals between group 1 and
group 3 (p < 0.05), while there was statistically significant difference for chrome, manganese, iron, cobalt and nickel (p < 0.05), but zinc and lead (p > 0.05) between group 2 and 3.
Conclusion Air pollutants of Pb and Zn resulting mostly from combustion of fossil fuels and certain special industrial process in Kirikkale
may be a risk factor for the high pregnancy loses by changing endometrial homeostasis. 相似文献
986.
Yannopoulos PC 《Environmental monitoring and assessment》2007,135(1-3):163-180
An economic and quick methodology for performing a preliminary spatial assessment of a city air quality with the purpose to
identify locations and zones susceptible to high pollution levels is proposed. A Patras case-study is selected, regarding
the air pollutants of sulfur dioxide (SO2) and oxides of nitrogen (NOx). A total number of 451 samples of short duration, of which 225 were randomly picked in morning rush hours and 226 within
evening rush hours, were collected from 50 locations of the major Patras area during a year period, when peaks of primary
air pollutants usually occur. Concentration measurements at prescribed locations used to statistically calculate spatial average
concentrations approximating 1-h mean values with mean probable errors less than 25.9% for SO2, NO and NOx and less than 15.5% for NO2. Then iso-concentration contour diagrams plotted indicate high pollution zones and possibly appropriate locations for continuous
or random monitoring according to the European Community (EC) Directives. The 1-h mean concentrations were in good correlation
to the corresponding traffic rates and useful relationships are given (0.54 ≤ r ≤ 0.63). In addition, comparisons with data available for other cities, as well as with the limit and guide values provided
by the EC and the World Health Organization (WHO) were given. The present data could be useful for the design and optimization
of a city network of stations for monitoring air quality, for environmental impact assessments, future reference and comparisons
due to city development needs, as well as for validating dispersion models. 相似文献
987.
This study compared three forecasting models based on the mean absolute percentage errors (MAPE) of their accuracy in forecasting
air pollution in a traffic tunnel: the Grey model (GM), the combination model used four sample point and five sample point
prediction with GM (1,1)(GM(1,1)4 + 5), and the modified grey model (MGM). An MGM was combined using the four points of the original sequence using the original
grey prediction GM (1,1) for short-term forecasting. The proposed method cannot only enhance the prediction accuracy of the
original grey model, but can also solve the jump data forecasting problem something for which the original grey model is inappropriate.
The MAPE was applied to the models, and the MGM found the proposed method to be simple and efficient. The MAPE of MGM, calculated
over 3 h of forecasts, were as follows: 10.12 (Upwind), 10.07 (Middle) and 7.68 (Downwind) for CO; 10.79 (Upwind), 6.05 (Middle)
and 5.98 (Downwind) for NO
x
, and 11.67 (Upwind), 7.32 (Middle) and 4.56 (Downwind) for NMHC. The MGM model results reveal that the combined forecasts
can significantly decrease the overall forecasting error. Results of this demonstrate that MGM can accurately forecast air
pollution in the Kaohsiung Chung–Cheng Tunnel. 相似文献
988.
This paper presents the externalities of sulfur dioxide (SO2) in the Taichung metropolitan, Taiwan. The human effects of SO2 from stationary sources are a key element for local air quality management. A methodology to evaluate those effects in monetary
term had been adapted and applied. This method was modified from the EU-based impact pathway approach link to the skill of
geographic information systems. The studied area was divided into 66 districts and the quantity of SO2 was allocated to each district. Then, the ambient concentration of SO2 was estimated by using the ordinary kriging method. A risk analysis was employed to characterize the health impacts caused
by SO2. Finally, a monetary transfer approach based on the European data was conducted to estimate local damage costs per ton of
SO2. Health impacts, especially acute mortality, dominate in term of costs. The calculation showed that damage costs ranged from
0.56 to 7.38 USD/kg SO2 based on the 2002 emission data. The results could be used in the internalization of SO2 externalities and management of the stationary sources in the studied area. This paper also concludes that the externalities
caused by stationary-related SO2 emissions are some 28.5 million US dollars in Taichung metropolitan (Taiwan) in 2002. 相似文献
989.
Yazvenko SB McDonald TL Blokhin SA Johnson SR Meier SK Melton HR Newcomer MW Nielson RM Vladimirov VL Wainwright PW 《Environmental monitoring and assessment》2007,134(1-3):45-73
Exxon Neftegas Limited, operator of the Sakhalin-1 consortium, is developing oil and gas reserves on the continental shelf
off northeast Sakhalin Island, Russia. DalMorNefteGeofizika (DMNG), on behalf of the Sakhalin-1 consortium, conducted a 3-D
seismic survey of the Odoptu license area during 17 August–9 September 2001. A portion of the primary known feeding area of
the endangered western gray whale (Eschrichtius robustus) is located adjacent to the seismic block. The data presented here were collected as part of daily monitoring to determine
if there was any measurable effect of the seismic survey on the distribution and abundance of western gray whales. Mitigation
and monitoring program included aerial surveys conducted between 19 July and 19 November using the methodology outlined by
the Southern California High Energy Seismic Survey team (HESS). These surveys provided documentation of the distribution,
abundance and bottom feeding activity of western gray whales in relation to seismic survey sounds. From an operations perspective,
the aerial surveys provided near real-time data on the location of whales in and outside the feeding area, and documented
whether whales were displaced out of an area normally used as feeding habitat. The objectives of this study were to assess
(a) temporal changes in the distribution and abundance of gray whales in relation to seismic survey, and (b) the influence
of seismic survey, environmental factors, and other variables on the distribution and abundance of gray whales within their
preferred feeding area adjacent to Piltun Bay. Multiple regression analysis revealed a limited redistribution of gray whales
southward within the Piltun feeding area when the seismic survey was fully operational. A total of five environmental and
other variables unrelated to seismic survey (date and proxies of depth, sea state and visibility) and one seismic survey-related
variable (seg3d, i.e., received sound energy accumulated over 3 days) had statistically significant effects on the distribution and abundance
of gray whales. The distribution of two to four gray whales observed on the surface (i.e., about five to ten whales in total)
has likely been affected by the seismic survey. However, the total number of gray whales observed within the Piltun feeding
area remained stable during the seismic survey.
M. W. Newcomer, Deceased. 相似文献
990.
Vincent G Kopferschmitt-Kubler MC Mirabel P Pauli G Millet M 《Environmental monitoring and assessment》2007,133(1-3):25-30
Quaternary Ammonium Compounds (QACs) are widely found in disinfectants used in hospitals. Benzalkonium chloride (BAC) and didecyldimethylammonium chloride (DDAC) predominate in the disinfecting formulations. These compounds are strong irritants and can play a role in the induction of Occupational Asthma among the professionals of health and cleaning. In order to evaluate the potential health effect of these quaternary ammonium compounds to hospital employers, the development of an analytical method for their quantification in indoor air was developed. DDAC aerosols are trapped by adsorption on XAD-2 resin SKC tube. The air in hospital buildings was sampled using a constant debit Gillian pump at a flow of 1.0 l/min (+/-5%). Ion Chromatography (IC) was chosen for the analysis of DDAC especially for its high sensitivity and specificity. The Limit of Detection (LOD) by IC for DDAC is 0.56 mug/ml. Therefore the LOD of atmospheric DDAC is 28 microg/m(3) with an air volume of 100 l and a desorption volume of 5 ml. All DDAC air samples were lower than the LOD of the analytical method by IC. Under the standard conditions of use of the disinfecting solutions (Surfanios, Ampholysine Plus and Amphospray 41), the insignificant volatility of DDAC would not seem to be able to contaminate the indoor hospital atmosphere during the disinfection process. However, the DDAC can contaminate working atmospheres if it is put in suspension by aerosolisation. 相似文献