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781.
Ali-Khodja H Belaala A Demmane-Debbih W Habbas B Boumagoura N 《Environmental monitoring and assessment》2008,138(1-3):219-231
Total suspended particulate matter and deposition fluxes of particles were investigated in the town of Didouche Mourad which
is located 13 km north of Constantine. Samples of air particulate matter were collected at one site located in the heart of
the town and situated 3 km north of a cement plant. Samples were collected from 2 November 2002 to 28 April 2003 every 3 days
using a high volume air sampler. Sampling intervals were 24 h in all cases. During the same period, samples of dust fallout
were collected at the same site. Samples were collected at 30-day intervals. Lead, chromium, manganese, nickel, copper, cobalt
and cadmium deposition fluxes were measured and both the soluble and insoluble fractions were determined. Furthermore, the
information gathered by this study was correlated with the corresponding hourly weather data provided by a weather station
installed at the study station. The possible sources for dust and trace metals were analyzed by comparing average contributions
of wind aspects to the concentrations and depositions of mass and chemical species with the average frequencies of wind direction.
The mean concentration was 300 μg/m3. The average dust deposition rate through the period of study was 221 mg/(m2.day). Results indicate that anthropogenic sources contribute greatly to trace elements. An exposure assessment to the heavy
metals taking into account the inhalation route and soil dust ingestion was carried out and allowed direct comparison of trace
metal intakes via these routes. 相似文献
782.
Diapouli E Chaloulakou A Mihalopoulos N Spyrellis N 《Environmental monitoring and assessment》2008,136(1-3):13-20
Simultaneous indoor and outdoor PM10 and PM2.5 concentration measurements were conducted in seven primary schools in the Athens area. Both gravimetric samplers and continuous
monitors were used. Filters were subsequently analyzed for anion species. Moreover ultrafine particles number concentration
was monitored continuously indoors and outdoors. Mean 8-hr PM10 concentration was measured equal to 229 ± 182 μg/m3 indoors and 166 ± 133 μg/m3 outdoors. The respective PM2.5 concentrations were 82 ± 56 μg/m3 indoors and 56 ± 26 μg/m3 outdoors. Ultrafine particles 8-h mean number concentration was measured equal to 24,000 ± 17,900 particles/cm3 indoors and 32,000 ± 14,200 particles/cm3 outdoors. PM10 outdoor concentrations exhibited a greater spatial variability than the corresponding PM2.5 ones. I/O ratios were close or above 1.00 for PM10 and PM2.5 and smaller than 1.00 for ultrafine particles. Very high I/O ratios were observed when intense activities took place. The
initial results of the chemical analysis showed that accounts for the 6.6 ± 3.5% of the PM10 and for the 3.1 ± 1.4%.The corresponding results for PM2.5 are 12.0 ± 7.7% for and 3.1 ± 1.9% for . PM2.5
indoor concentrations were highly correlated with outdoor ones and the regression line had the largest slope and a very low
intercept, indicative of no indoor sources of fine particulate . The results of the statistical analysis of indoor and outdoor concentration data support the use of as a proper surrogate for indoor PM of outdoor origin. 相似文献
783.
Vanerkar AP Kulkarni NP Zade PD Kamavisdar AS 《Environmental monitoring and assessment》2008,143(1-3):239-245
As mining operations get mechanized, the rate of profit generation increases and so do the rate of occupational hazards. This study deals with one such hazard - occupational vibration. The present study was carried out to determine the whole body vibration (WBV) exposure of the heavy earth moving machinery (HEMM) operators in two types of metalliferous mines in India, when they were engaged in the mining activity. Cross-comparison was done of the vibration dose value (VDV) for HEMM operators as well as each type of mine. The VDV for the shovel operator in bauxite mine was observed to be 13.53 +/- 5.63 m/s(7/4) with 25% of the readings higher than the prescribed limit whereas in iron ore mine VDV for dumper operator was 10.81 +/- 3.44 m/s(7/4) with 14.62% readings on the higher side. Cross-comparison of the VDV values for bauxite and iron ore mines revealed that it was 9.57 +/- 4.93 and 8.21 +/- 5.12 m/s(7/4) with 21.28 and 14.95% of the readings on the higher side respectively. The Student's t test level was found to be insignificant for both type of mines, indicating that the WBV exposure is not dependent on the type of mine but is dependent on the working condition and type of HEMM in operation. 相似文献
784.
Golobocanin D Zujić A Milenković A Miljević N 《Environmental monitoring and assessment》2008,142(1-3):185-198
Bulk samples collected on a daily basis at three principal meteorological stations in central Serbia were analyzed on chloride (Cl(-)), nitrate [Formula: see text], sulfate [Formula: see text], sodium (Na(+)), ammonium [Formula: see text], potassium (K(+)), calcium (Ca(2+)), and magnesium (Mg(2+)) in addition to precipitation amount, pH and conductivity measurements over the period 1998-2004. The data were subjected to variety of analyses (linear regression, principal component analysis, time series analysis) to characterize precipitation chemistry in the study area. The most abundant ion was [Formula: see text] with annual volume weighted mean concentration of 242 microeq L(-1). Neutralization of precipitation acidity occurs both as a result of the dissolution of alkaline compounds containing Ca(2+), Mg(2+), and K(+) as well as the absorption of ammonia. The ratio of [Formula: see text] was above 5, which indicated that the combustion process of low-grade domestic lignite for electricity generation from coal-fired thermal power plants was the main source of pollution in the investigated area. A considerable mean annual bulk wet deposition of SO(4)-S determined by precipitation amount and concentrations of sulfate in the precipitation was calculated to be 12-35 kg ha(-1). 相似文献
785.
Seasonal variations of heavy metal contamination in river Gomti of Lucknow city region 总被引:2,自引:0,他引:2
Lohani MB Singh A Rupainwar DC Dhar DN 《Environmental monitoring and assessment》2008,147(1-3):253-263
The present study deals with the seasonal variations in the concentrations of heavy metals namely chromium, lead and mercury by using spectrophotometric methods. The water samples were collected at regular intervals from five selected sites of river Gomti in the pre-monsoon period (months of February-May) and the post monsoon period (months of October-January). The concentrations of chromium (VI) and mercury (II) were determined by using Genesys-10 UV-VIS Spectrophotometer while lead (II) concentrations were determined using Atomic Absorption Spectrophotometer, Perkin-Elmer 5000 model. The concentrations of all the three metals were found to be higher in the pre-monsoon period than in the post-monsoon period. The statistical analysis of the data was discussed in both the seasons in terms of mean, standard deviation and coefficient of variation. 相似文献
786.
Singh M Kalra N Chakraborty D Kamble K Barman D Saha S Mittal RB Pandey S 《Environmental monitoring and assessment》2008,142(1-3):97-108
This study aims in linking the biophysical and socioeconomic data base layers with the technical coefficients or simulation models for agri-production estimates and land use planning under normal and extreme climatic events, and exploring the resource and inputs management options in village Shikohpur, Gurgaon district located in the northwest part of India. The socioeconomic profile of Shikohpur is highly skewed with mostly small and marginal farmers. Though the areas under wheat in Shikohpur are increasing, the productivity is declining or remaining stagnant over the years. Most of the area during kharif season (June-September) remains fallow. Pearl millet based cropping systems (pearl millet-mustard and pearl millet-wheat) are predominant. Soils are mostly loamy sand to sandy loam with average of 70-80% sand content. Organic C content in soil is less than 0.3%, due to high prevailing temperature with little rainfall and also intensive agriculture followed in this region. Though the annual average seasonal rainfall in Gurgaon did not have much variation over the years, occurrence of extreme climate events has increased in the last two decades. The crop intensity is low and the water table is declining. Water and nitrogen production functions were developed for the important crops of the region, for their subsequent use in scheduling of the inputs. InfoCrop, WTGROWS and technical coefficients were used for crop planning and resource management under climate change and its variability, extreme events, limited resource availability and crop intensification. These will help in disseminating necessary agro-advisories to the farmers so that they will be able to manipulate the inputs and agronomic management practices for sustained agricultural production under normal as well as extreme climatic conditions. 相似文献
787.
Rai UN Dubey S Shukla OP Dwivedi S Tripathi RD 《Environmental monitoring and assessment》2008,144(1-3):469-481
The water bodies of Lucknow, Unnao and Kanpur (U.P.), India polluted through various point and non point sources were found to be either eutrophic or oligotrophic in nature. These water bodies supported a great number of algal diversity, which varied seasonally depending upon the physico-chemical properties of water. Further, the water bodies polluted through non point sources supports diverse algal species, while the water bodies polluted through point sources supports growth of tolerant blue green algae. High biomass producing algal species growing in these water bodies have accumulated significant amount of metals in their tissues. Maximum amount of Fe was found accumulated by species of Oedogonium sp. II (20,523.00 mug g(-1) dw) and Spirogyra sp. I (4,520.00 mug g(-1) dw), while maximum Chromium (Cr) was found accumulated in Phormedium bohneri (2,109.00 mug g(-1) dw) followed by Oscillatoria nigra (1,957.88 mug g(-1) dw) and Oedogonium sp. I (156.00 mug g(-1) dw) and Ni in Ulothrix sp. (495.00 mug g(-1) dw). Results showed that some of these forms growing in polluted environment and accumulating high amounts of toxic metals may be used as bioindicator species, however, their performance in metal contaminated water under different ecological niche is to be ascertained. 相似文献
788.
Michael G. Hutchins Amelie Deflandre-Vlandas Paulette E. Posen Helen N. Davies Colin Neal 《Environmental Modeling and Assessment》2010,15(2):93-109
A combined semi-distributed hydrological model (CASCADE/QUESTOR) is used to evaluate the steady-state that may be achieved
after changes in land-use or management and to explore what additional factors need to be considered in representing catchment
processes. Two rural headwater catchments of the River Derwent (North Yorkshire, UK) were studied where significant change
in land-use occurred in the 1990s and the early 2000s. Much larger increases in mean nitrate concentration (55%) were observed
in the catchment with significant groundwater influence (Pickering Beck) compared with the surface water-dominated catchment
(13% increase). The increases in Pickering Beck were considerably greater than could be explained by the model in terms of
land-use change. Consequently, the study serves to focus attention on the long-term increases in nitrate concentration reported
in major UK aquifers and the ongoing and chronic impact this trend is likely to be having on surface water concentrations.
For river environments, where groundwater is a source, such trends will mask the impact of measures proposed to reduce the
risk of nitrate leaching from agricultural land. Model estimates of within-channel losses account for 15–40% of nitrate entering
rivers. 相似文献
789.
Langston WJ O'Hara S Pope ND Davey M Shortridge E Imamura M Harino H Kim A Vane CH 《Environmental monitoring and assessment》2012,184(1):289-311
Biomonitoring of contaminants (metals, organotins, polyaromatic hydrocarbons (PAHs), PCBs) was undertaken in Milford Haven
Waterway (MHW) and a reference site in the Tywi Estuary (St Ishmael/Ferryside) during 2007–2008. Bioindicator species encompassed
various uptake routes—Fucus vesiculosus (dissolved contaminants); Littorina littorea (grazer); Mytilus edulis and Cerastoderma edule (suspension feeders); and Hediste (=Nereis) diversicolor (sediments). Differences in feeding and habitat preference have subtle implications for bioaccumulation trends though, with
few exceptions, contaminant burdens in MHW were higher than the Tywi reference site, reflecting inputs. Elevated metal concentrations
were observed at some MHW sites, whilst As and Se (molluscs and seaweed) were consistently at the higher end of the UK range.
However, for most metals, distributions in MH biota were not exceptional. Several metal-species combinations indicated increases
in bioavailability upstream, which may reflect the influence of geogenic/land-based sources—perhaps enhanced by lower salinity.
TBT levels in MH mussels were below OSPAR toxicity thresholds and in the Tywi were close to zero. Phenyltins were not accumulated
appreciably in M. edulis, whereas some H. diversicolor populations appear subjected to localized (historical) sources. PAHs in H. diversicolor were distributed evenly across most of MHW, although acenaphthene, fluoranthene, pyrene, benzo(a)anthracene and chrysene were highest at one site near the mouth; naphthalenes in H. diversicolor were enriched in the mid-upper Haven (a pattern seen in M. edulis for most PAHs). Whilst PAH (and PCB) concentrations in MH mussels were mostly above reference and OSPAR backgrounds, they
are unlikely to exceed ecotoxicological thresholds. Bivalve Condition indices (CI) were highest at the Tywi reference site
and at the seaward end of MH, decreasing upstream—giving rise to several significant (negative) relationships between CI and
body burdens. Despite the possible influence of salinity gradient as a complicating factor, multivariate analysis indicated
that a combination of contaminants could influence the pattern in condition (and the biomarkers metallothionein and TOSC).
Integrating bioaccumulation data with biological and biochemical endpoints is seen as a useful way to discriminate environmental
quality of moderately contaminated areas such as MHW and to prioritise cause and effect investigations. 相似文献
790.
Fernandes CE Das A Nath BN Faria DG Loka Bharathi PA 《Environmental monitoring and assessment》2012,184(5):2677-2689
We investigated the influence on bacterial community and biochemical variables through mechanical disturbance of sediment-akin
to small-scale mining in Kalbadevi beach, Ratnagiri, a placer-rich beach ecosystem which is a potential mining site. Changes
were investigated by comparing three periods, namely phase I before disturbance, phase II just after disturbance, and phase
III 24 h after disturbance as the bacterial generation time is ≤7 h. Cores from dune, berm, high-, mid-, and low-tide were
examined for changes in distribution of total bacterial abundance, total direct viability (counts under aerobic and anaerobic
conditions), culturability and biochemical parameters up to 40 cm depth. Results showed that bacterial abundance decreased
by an order from 106 cells g − 1 sediment, while, viability reduced marginally. Culturability on different-strength nutrient broth increased by 155% during
phase II. Changes in sedimentary proteins, carbohydrates, and lipids were marked at berm and dune and masked at other levels
by tidal influence. Sedimentary ATP reduced drastically. During phase III, Pearson’s correlation between these variables evolved
from non-significant to significant level. Thus, simulated disturbance had a mixed effect on bacterial and biochemical variables
of the sediments. It had a negative impact on bacterial abundance, viability and ATP but positive impact on culturability.
Viability, culturability, and ATP could act as important indicators reflecting the disturbance in the system at short time
intervals. Culturability, which improved by an order, could perhaps be a fraction that contributes to restoration of the system
at bacterial level. This baseline information about the potential mining site could help in developing rational approach towards
sustainable harnessing of resources with minimum damage to the ecosystem. 相似文献