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821.
An air quality sampling program was designed and implemented to collect the baseline concentrations of respirable suspended
particulates (RSP = PM10), non-respirable suspended particulates (NRSP) and fine suspended particulates (FSP = PM2.5). Over a three-week period, a 24-h average concentrations were calculated from the samples collected at an industrial site
in Southern Delhi and compared to datasets collected in Satna by Envirotech Limited, Okhla, Delhi in order to establish the
characteristic difference in emission patterns. PM2.5, PM10, and total suspended particulates (TSP) concentrations at Satna were 20.5 ± 6.0, 102.1 ± 41.1, and 387.6 ± 222.4 μg m−3 and at Delhi were 126.7 ± 28.6, 268.6 ± 39.1, and 687.7 ± 117.4 μg m−3. Values at Delhi were well above the standard limit for 24-h PM2.5 United States National Ambient Air Quality Standards (USNAAQS; 65 μg m−3), while values at Satna were under the standard limit. Results were compared with various worldwide studies. These comparisons
suggest an immediate need for the promulgation of new PM2.5 standards. The position of PM10 in Delhi is drastic and needs an immediate attention. PM10 levels at Delhi were also well above the standard limit for 24-h PM10 National Ambient Air Quality Standards (NAAQS; 150 μg m−3), while levels at Satna remained under the standard limit. PM2.5/PM10 values were also calculated to determine PM2.5 contribution. At Satna, PM2.5 contribution to PM10 was only 20% compared to 47% in Delhi. TSP values at Delhi were well above, while TSP values at Satna were under, the standard
limit for 24-h TSP NAAQS (500 μg m−3). At Satna, the PM10 contribution to TSP was only 26% compared to 39% in Delhi. The correlation between PM10, PM2.5, and TSP were also calculated in order to gain an insight to their sources. Both in Satna and in Delhi, none of the sources
was dominant a varied pattern of emissions was obtained, showing the presence of heterogeneous emission density and that nonrespirable
suspended particulate (NRSP) formed the greatest part of the particulate load. 相似文献
822.
Singh S Sharma DK Dhar S Kumar A Kumar A 《Environmental monitoring and assessment》2007,130(1-3):301-309
Two measurement campaigns were conducted in two sampling sites, An Thinh and Duy Minh, in northern Vietnam during the months
of November–December 2000 and November 2001–February 2002 in order to investigate the extend of the particulate air pollution
from the Pha Lai coal fired power plant. Fine particle samples were analyzed by Energy Dispersive X-Ray Fluorescence spectrometry
and soot samples were analyzed by reflectometer. The result showed that high concentration of soot and elements mostly coincided
with the air masses originating from the power plant. Sea spray aerosol was found to be the major source of chlorine at both
sites. Ratios of specific elements and principal component analysis (PCA) revealed that coal combustion was the main contributor
to the air pollution at both sites. PCA also indicated that there were other sources responsible for the elements emission,
probably the influence of long distance transport and Asian Brown Cloud. 相似文献
823.
Cadmium pollution resulted from fertilizer applications were studied by determining cadmium levels in agricultural and non-agricultural soils of Bafra and Çar?amba plains. Soil samples of 68 were collected from agricultural (34) and non-agricultural (34) areas. The sample of 2 g was placed in a test tube and digested with hydrochloric acid and nitric acid mixture (3:1, v/v) in an aluminum block. Taking up the evaporated residue was dissolved in 1% nitric acid and total cadmium concentrations were determined with GF-AAS. Mean level of cadmium contents were found in agricultural areas 0.162?±?0.078 for Çar?amba and 0.433?±?0.288 mg kg?1 for Bafra. The accuracy of the method was tested with determining cadmium contents of standard reference material and cadmium spiked soil samples. 相似文献
824.
Demirel Z 《Environmental monitoring and assessment》2007,132(1-3):15-23
In this study, heavy metal contents of groundwater from the Mersin aquifer were determined with photometric methods and used
to determine the main factors controlling the pollution of groundwater in the area. Using MapInfo GIS software, spatial analysis
and integration were carried out for mapping drinking water quality in the basin. From the photometric heavy metal analysis,
it is inferred that the excess concentration of Fe, Ni, Mn, Mo and Cu at some locations is the cause of undesirable quality
for drinking purposes. Similarly, the EC thematic map shows that considerable areas in the basin are having high salinity
hazards. The reason for excess concentration of various heavy metals is the industrial activities and petroleum pipelines
and salinity levels show the sea water intrusion. 相似文献
825.
Syed S 《Environmental monitoring and assessment》2007,130(1-3):311-322
‘Metal ash’ presents a waste disposal problem in most of the developing countries as the industries employ obsolete technologies.
In this paper we describe analysis of tin ash, zinc ash and aluminium ash by means of optical methods, such as X-ray diffraction
(XRD), inductively coupled plasma mass spectrometry (ICP-MS), electron probe micro analysis (EPMA), scanning electron microscopy
(SEM) and chemical methods. The results of tin ash obtained by XRD method matched well with the cassiterite, a naturally occurring
mineral of tin. ICP-MS studies reveal the presence of a large number of tracer metals, which may cause pollution by tertiary
dispersion and this aspect is discussed. Conversely, the data generated by chemical methods are limited. However, the methods
are simple and cost-effective. Then, they can easily be adopted by low-budget industries. Simple and cost-effective process
to recover tin from tin ash is described. It is based on heating tin ash with sodium cyanide to about 900°C to separate tin
component from the metal ash. The process recovers good quality tin and offers a very high yield. The process can be scaled
up to small pilot plant. 相似文献
826.
Jaji MO Bamgbose O Odukoya OO Arowolo TA 《Environmental monitoring and assessment》2007,133(1-3):473-482
The quality of Ogun river in South-West, Nigeria was studied by a field survey for a period of 1 year (covering dry season
and rainy season). Water samples were collected from thirteen sites and analysed for physico-chemical and bacteriological
parameters as well as heavy metals using standard methods. Generally, the values obtained for turbidity, phosphate, oil and
grease, iron and faecal coliform from all the sites in both seasons were above the maximum acceptable limit set by the World
Health Organization (WHO) for drinking water. Also, the manganese content from all the sites in the dry season, lead concentrations
from three sites in the dry season and cadmium concentrations from some sites in both seasons were above the WHO limit. The
values obtained for total dissolved solids, dissolved oxygen and chloride at site M in the dry season and nitrate at site
J in the rainy season were also above the WHO limit. Pollution of Ogun river water along its course is evidenced by the high
concentrations of pollution indicators, nutrients and trace metals above the acceptable limit. This poses a health risk to
several rural communities who rely on the river primarily as their source of domestic water. The study showed a need for continuous
pollution monitoring programme of surface waters in Nigeria. 相似文献
827.
Kraigher H Al Sayegh Petkovsek S Grebenc T Simoncic P 《Environmental monitoring and assessment》2007,128(1-3):31-45
Mycorrhiza is the main spatial and temporal linkage between different constituents in a forest ecosystem. The functional compatibility
and stress tolerance of ectomycorrhizal types is species specific, and therefore the information on the ectomycorrhizal community
structure can add to the understanding of processes in forest ecosystems and can also be applied as tools for bioindication
of pollution stress in forest soils. We have studied the effects of pollution (N and S) on trees and forest soils by: (1)
quantification of ECM types diversity as in situ indicators in forest stands, (2) determination and quantification of pollution-sensitive or -insensitive ECM types as passive
monitors, (3) root growth and development of ECM on nonmycorrhizal spruce seedlings, planted at the studied sites (active
monitors), and (4) ECM infection (a bioassay based on mycorrhizal inoculum potential) of seedlings in an experimental set-up
as ex situ testers. ECM species richness for Norway spruce trees (Picea abies) showed higher values in unpolluted sites than in polluted ones, while the differences were not significant for European
beech trees (Fagus sylvatica). As pollution-sensitive or -insensitive ECM species in spruce forests, we suggest Hydnum rufescens (sensitive) and Paxillus involutus (unsensitive). Mycorrhizal potential in Norway spruce seedlings as a bioassay for soil N and S pollution was effective, and
is suggested as an additional, standardized and widely comparable system in bioindication of soil pollution. 相似文献
828.
Libby, Montana is the only PM2.5 nonattainment area in the western United States with the exceptions of parts of southern California. During January through
March 2005, a particulate matter (PM) sampling program was conducted within Libby’s elementary and middle schools to establish
baseline indoor PM concentrations before a wood stove change-out program is implemented over the next several years. As part
of this program, indoor concentrations of PM mass, organic carbon (OC), and elemental carbon (EC) in five different size fractions
(>2.5, 1.0–2.5, 0.5–1.0, 0.25–0.5, and <0.25 μm) were measured. Total measured PM mass concentrations were much higher inside
the elementary school, with particle size fraction (>2.5, 0.5–1.0, 0.25–0.5, and <0.25 μm) concentrations between 2 and 5
times higher when compared to the middle school. The 1.0–2.5 μm fraction had the largest difference between the two sites,
with elementary school concentrations nearly 10 times higher than the middle school values. The carbon component for the schools’
indoor PM was found to be predominantly composed of OC. Measured total OC and EC concentrations, as well as concentrations
within individual size fractions, were an average of two to five times higher at the elementary school when compared to the
middle school. For the ultrafine fraction (<0.25), EC concentrations were similar between each of the schools. Despite the
differences in concentrations between the schools at the various fraction levels, the OC/EC ratio was determined to be similar. 相似文献
829.
Minero C Maurino V Bono F Pelizzetti E Marinoni A Mailhot G Carlotti ME Vione D 《Chemosphere》2007,68(11):2111-2117
The effect of selected organic and inorganic compounds, present in snow and cloudwater was studied. Photolysis of solutions of nitrate to nitrite was carried out in the laboratory using a UVB light source. The photolysis and other reactions were then modelled. It is shown that formate, formaldehyde, methanesulphonate, and chloride to a lesser extent, can increase the initial formation rate of nitrite. The effect, particularly significant for formate and formaldehyde, is unlikely to be caused by scavenging of hydroxyl radicals. The experimental data obtained in this work suggest that possible causes are the reduction of nitrogen dioxide and nitrate by radical species formed on photooxidation of the organic compounds. Hydroxyl scavenging by organic and inorganic compounds would not affect the initial formation rate of nitrite, but would protect it from oxidation, therefore, increasing the concentration values reached at long irradiation times. The described processes can be relevant to cloudwater and the quasi-liquid layer on the surface of ice and snow, considering that in the polar regions irradiated snow layers are important sources of nitrous acid to the atmosphere. Formate and (at a lesser extent) formaldehyde are the compounds that play the major role in the described processes of nitrite/nitrous acid photoformation by initial rate enhancement and hydroxyl scavenging. 相似文献
830.
Pipeline crossing construction alters river and stream channels, hence may have detrimental effects on aquatic ecosystems.
This review examines the effects of crossing construction on fish and fish habitat in rivers and streams, and recommends an
approach to monitoring and assessment of impacts associated with these activities. Pipeline crossing construction is shown
to not only compromise the integrity of the physical and chemical nature of fish habitat, but also to affect biological habitat
(e.g., benthic invertebrates and invertebrate drift), and fish behavior and physiology. Indicators of effect include: water
quality (total suspended solids TSS), physical habitat (substrate particle size, channel morphology), benthic invertebrate
community structure and drift (abundance, species composition, diversity, standing crop), and fish behavior and physiology
(hierarchy, feeding, respiration rate, loss of equilibrium, blood hematocrit and leukocrit levels, heart rate and stroke volume).
The Before-After-Control-Impact (BACI) approach, which is often applied in Environmental Effects Monitoring (EEM), is recommended
as a basis for impact assessment, as is consideration of site-specific sensitivities, assessment of significance, and cumulative
effects. 相似文献