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941.
Kalbande DM Dhadse SN Chaudhari PR Wate SR 《Environmental monitoring and assessment》2008,138(1-3):233-238
Abstract Industrial development and consumption of petroleum products leads to increase air pollution levels especially in
urban and industrial areas. Heavy metal components associated with air pollutants have far reaching effects with respect to
economic and ecological importance of pollens. The pollens are male reproductive organs of the plant and travel through air
from flower to flower for pollination purpose. During this period they are exposed to air pollutants. Present investigation
thus pertains to study of effect of air pollutants on pollens especially biosorption and bioaccumulation of heavy metals.
The pollens of three commonly occurring plants namely Cassia siamea, Cyperus rotundus, Kigelia pinnata have been studied from the NH-6 of Nagpur city, India. The pollens exposed to polluted air showed the presence of higher
concentrations of Ca, Al and Fe as compared to unexposed pollens. Higher concentration of these metals was observed in Cyperus rotundus followed by Cassia siamea and Kigelia pinnata. These results indicate that pollens act as good indicator of air pollution giving results in short time of exposure of 5–10 h.
Apart from this, it is also reported that some of these metals play crucial role in the metabolic activity in pollens for
example Calcium is necessary for growth of pollen tube and other metabolic activities in pollens. The presence of these metals
in pollens may also enhance the allergenicity of the pollens. Similarly accumulation of heavy metals may also deteriorate
the quality of pollen for their economical use. The viability of pollen is also affected by these pollutants in sensitive
species leading to impairment of their fertility. 相似文献
942.
Wet weather impact on trihalomethane formation potential in tributaries to drinking water reservoirs
During rain storm events, land surface runoff and resuspension of bottom sediments cause an increase in Trihalomethane (THM)
precursors in rivers. These precursors, when chlorinated at water treatment facilities will lead to the formation of THMs
and hence impact drinking water resources. In order to evaluate the wet weather impact on the potential formation of THMs,
river samples were collected before, during and after three rain storms ranging from 15.2 to 24.9 mm precipitation. The samples
were tested for THM formation potential and other indicators including UV254 absorbance, turbidity and volatile suspended
solid (VSS). Average levels of THMs increased from 61 μg/l during dry weather to 131 μg/l during wet weather, and then went
back to 81 μg/l after rain ended. Wet weather values of THM are well above the maximum contaminant level (MCL) 80 μg/l, set
by EPA for drinking water. THM indicators also exhibited similar trends. Average levels increased from 0.6 to 1.8 abs; 2.6
to 6 ntu; and 7.5 to 15 mg/l respectively for UV254, turbidity and VSS. A positive correlation was observed between THM formation
and THM indicators. The t-test of significance (p-value) was less than 0.05 for all indicators, and R values ranged from 0.85 to 0.92 between THMs and the indicators, and 0.72 to 0.9 among indicators themselves. 相似文献
943.
944.
Affum HA Oduro-Afriyie K Nartey VK Adomako D Nyarko BJ 《Environmental monitoring and assessment》2008,137(1-3):15-24
Lichens collected in an unpolluted forest (background) in November 2004, transplanted at 41 sampling sites along the Madina-Tetteh
Quarshie road, retrieved in February 2005 and analysed were found to contain higher concentrations of Manganese (Mn), Vanadium
(V), lead, Cadmium (Cd), Chromium (Cr) and Nickel (Ni) than in the background area. Observations showed that of all the heavy
metals studied, Manganese concentrations were highest at all sampling points with maximum values around a traffic light, an
intersection and car fitting/mechanic workshops. Significant correlations were found between Ni and Mn, Mn and Cr and Mn and
V. Statistical analysis also revealed a relatively even dispersion of the studied elements on the eastern side of the road
than on the western side. 相似文献
945.
Qu G Omotoso MM Gamal El-Din M Feddes JJ 《Environmental monitoring and assessment》2008,144(1-3):277-283
Odorous air samples collected from several sources were presented to an olfactometer, an electronic nose, a hydrogen sulfide (H(2)S) detector and an ammonia (NH(3)) detector. The olfactometry measurements were used as the expected values while measurements from the other instrumentation values became input variables. Five hypotheses were established to relate the input variables and the expected values. Both linear regression and artificial neural network analyses were used to test the hypotheses. Principal component analysis was utilized to reduce the dimensionality of the electronic nose measurements from 33 to 3 without significant loss of information. The electronic nose or the H(2)S detector can individually predict odor concentration measurements with similar accuracy (R (2) = 0.46 and 0.50, respectively). Although the NH(3) detector alone has a very poor relationship with odor concentration measurements, combining the H(2)S and NH(3) detectors can predict odor concentrations more accurately (R (2) = 0.58) than either individual instrument. Data from the integration of the electronic nose, H(2)S, and NH(3) detectors produce the best prediction of odor concentrations (R (2) = 0.75). With this accuracy, odor concentration measurements can be confidently represented by integrating an electronic nose, and H(2)S and NH(3) detectors. 相似文献
946.
Metal pollution assessment of sediment and water in the Shur River 总被引:13,自引:0,他引:13
Karbassi AR Monavari SM Nabi Bidhendi GR Nouri J Nematpour K 《Environmental monitoring and assessment》2008,147(1-3):107-116
Intensified industrialization and human activities have resulted in the release of various contaminants into the environment. Among them, heavy metals are often present as a result of mining, milling and industrial manufacturing. In the present investigation, bulk concentrations Pb, Cd, Zn, Cu, Fe, Ca and Al in Shur River (Iran) bed sediments and water around the Sarcheshmeh copper mine were measured from several sample locations. In addition, partitioning was assessed to determine the proportions of metals in different forms. The degree of sediment contamination was evaluated using an Enrichment Factor (EF) and geo-accumulation index (I (geo)) and a newly developed pollution index (I (POLL)). Elevated metals in sediment and water were found to be correlated with areas of the river that were proximal to direct and indirect mining activities. Cadmium and Zn showed the highest pollution index. Cluster analysis was performed in order to assess heavy metal interactions between water and sediment. Chemical partitioning studies revealed that organic metallic bonds were not significantly present in the sediment of the Shur River. 相似文献
947.
A new method for municipal solid waste incinerator (MSWI) fly ash inertization, based on colloidal silica 总被引:1,自引:0,他引:1
Bontempi E Zacco A Borgese L Gianoncelli A Ardesi R Depero LE 《Journal of environmental monitoring : JEM》2010,12(11):2093-2099
Municipal solid waste incineration (MSWI) is a straightforward way to manage waste, however the disposal of process byproducts, mainly bottom and fly ash, is still a problem, because of their hazardous contents. Fly ash is a byproduct of many other processes that involve combustion to produce energy. In this paper we present and discuss a new method for MSWI fly ash inertization, mainly based on the use of colloidal silica as a stabilization agent for metals. In the patented procedure, fly ash of different provenance can be used to produce an inert and non-hazardous material, that can be reused. In fact to make the recovery process more efficient, landfilling should be totally avoided. For this reason, to enhance the possibility of reuse, a washing process, for salts recovery, is proposed as a final step of the inertization procedure. The obtained inert material is called COSMOS (COlloidal Silica Medium to Obtain Safe inert), and it is composed of calcium carbonate, calcium sulfate, silicon oxide and a wide quantity of non-soluble amorphous compounds. COSMOS does not contain any corrosive salts. This makes it extremely interesting for cement industry applications with several other advantages, and environmental benefits. The new proposed inertization procedure appears very promising, because it allows MSWI fly ash to be considered a valuable resource. Thanks to the obtained results, a demonstration project, in the frame of LIFE+, has been funded by the European Commission (LIFE+ 2008 project ENV/IT/000434, ). 相似文献
948.
Concentration of heavy metals (Cd, Ni, Zn, Fe, Cu, Mn, Pb, Cr, Hg and As) in the waters of River Yamuna and in the soil of
agricultural fields along its course in Delhi are reported from 13 sites, spread through the Delhi stretch of Yamuna, starting
from the Wazirabad barrage till the Okhla barrage. Varying concentration of heavy metals was found. Peaks were observed in
samples collected downstream of Wazirabad and Okhla barrage, indicating the anthropogenic nature of the contamination. The
Wazirabad section of the river receives wastewater from Najafgarh and its supplementary drains, whereas the Shahdara drain
releases its pollution load upstream of the Okhla barrage. Average heavy metal concentration at different locations in the
river water varied in the order of Fe>Cr>Mn>Zn>Pb>Cu>Ni>Hg>As>Cd. The river basin soil shows higher level of contamination
with lesser variation than the water samples among sampling locations, thereby suggesting deposition over long periods of
time through the processes of adsorption and absorption. The average heavy metal concentration at different locations in soil
varied in the order of Fe>Mn>Zn>Cr>Pb>Ni>Hg>Cu>As>Cd. 相似文献
949.
Al-Tayar NG Nagaraja P Vasantha RA Shresta AK 《Environmental monitoring and assessment》2012,184(1):181-191
A simple, rapid, and sensitive method involving the interaction of 2,4-dinitrophenylhydrazine with imipramine hydrochloride
in presence of vanadium (V) in sulfuric acid medium has been proposed for the determination of vanadium. The purple-colored
product developed showed an absorption maximum at 560 nm and was stable for 24 h. The working curve was linear over the concentration
range of 0.1–2.8 μg ml − 1, with sensitivity of detection of 0.0124 μg ml − 1. Molar absorptivity and Sandell’s sensitivity were found to be 2.6 × 104 l/mol cm and 0.0039 μg cm − 1, respectively. The accuracy of the proposed method was assessed by Student’s t test and variance ratio F test, and the results were on par with the reported method. The method was successfully used in the determination of V in
water, human urine, soil, and plant samples, and it was free from interference by various concomitant ions. 相似文献
950.
de Figueiredo DR Ferreira RV Cerqueira M de Melo TC Pereira MJ Castro BB Correia A 《Environmental monitoring and assessment》2012,184(1):471-485
The information on bacterial community composition (BCC) in Portuguese water bodies is very scarce. Cértima River (central
western Portugal) is known to have high levels of pollution, namely organic. In the present work, the BCC from a set of 16
water samples collected from Cértima River Basin and its main tributaries was characterized using 16S rDNA–denaturing gradient
gel electrophoresis, a culture-independent molecular approach. Molecular data were related to environmental parameters through
multivariate analysis to investigate potential impact of water pollution along the river. Principal component analysis using
environmental data showed a water quality gradient from more pristine waters (at the mountain tributaries) to waters with
increasingly eutrophic potential (such as Fermentelos Lake). This gradient was mainly defined by factors such as organic and
inorganic nutrient sources, electrical conductivity, hydrogen carbonate concentration, and pH. Molecular results showed variations
in BCC along Cértima River Basin but in the main river section, a Bacteroidetes phylotype (Flavobacterium sp.) proved to be dominant throughout the river course. Multivariate analysis suggests that spatial variation of BCC along
the Cértima River Basin depended mainly on parameters such as Chl a, total suspended solid (TSS), total organic carbon, electrical conductivity, and HCO
_boxclose^-_{3}^{-} levels. Bacteroidetes phylotypes were all related to higher electrical conductivity and HCO3-_{3}^{-} levels although some of these were also correlated with high SO42-_{4}^{2-} and others with high soluble reactive phosphorus, nitrate, TN, and Kjeld-N levels. The Gammaproteobacteria occurrence was correlated with high SO42-_{4}^{2-} levels. One of the Betaproteobacteria phylotypes showed to correlate with low redox potential (Eh) and high temperature, pH, TSS, and Chl a levels while another one showed a negative correlation with Chl a values. 相似文献