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991.
Gowri VS Ramachandran S Ramesh R Pramiladevi IR Krishnaveni K 《Environmental monitoring and assessment》2008,138(1-3):41-49
Residential, industrial, commercial, institutional and recreational activities discharge degradable and non-degradable wastes
that reach the coastal water through rivers and cause coastal pollution. In the present study, mass transport of pollutants
by Adyar and Cooum Rivers to the coastal water as a result of land-based discharges was estimated during low tide. The lowest
and the highest flow recorded in Adyar varied from 514.59 to 2,585.08×106 litres/day. Similarly, the flow in Cooum River fluctuated between 266.45 and 709.34×106 litres/day. The present study revealed that the Adyar River transported 53.89–454.11 t/d of suspended solids, 0.06–19.64 t/d
of ammonia, 15.95–123.24 t/d of nitrate and 0.4–17.86 t/d of phosphate, 0.004–0.09 kg/d of cadmium, 0.15–1.29 kg/d of lead
and 3.03–17.58 kg/d of zinc to the coastal water owing to its high discharge. Similarly, the Cooum River transported 11.87–120.06 t/d
of suspended solids, 0.08–58.7 t/d of ammonia, 6.11–29.25 t/d of nitrate and 0.66–10.73 t/d of phosphate, 0.003–0.021 kg/d
of cadmium, 0.02–0.44 kg/d of lead and 1.36–3.87 kg/d of zinc. A higher concentration of suspended solids was noticed in post
monsoon and summer months. An increase in the mass transport of ammonia, nitrate, phosphate in summer months (April and May)
and an increase in the mass transport of cadmium, lead and zinc were observed in monsoon months (October–December) in both
the rivers. Thus mass transport of pollutants study reveal that Cooum and Adyar Rivers in Chennai contribute to coastal pollution
by transporting inorganic and trace metals significantly through land drainage. 相似文献
992.
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
993.
Pesch R Pehlke H Jerosch K Schröder W Schlüter M 《Environmental monitoring and assessment》2008,136(1-3):313-325
In this article a concept is described in order to predict and map the occurrence of benthic communities within and near the
German Exclusive Economic Zone (EEZ) of the North Sea. The approach consists of two work steps: (1) geostatistical analysis
of abiotic measurement data and (2) calculation of benthic provinces by means of Classification and Regression Trees (CART)
and GIS-techniques. From bottom water measurements on salinity, temperature, silicate and nutrients as well as from punctual
data on grain size ranges (0–20, 20–63, 63–2,000 μ) raster maps were calculated by use of geostatistical methods. At first
the autocorrelation structure was examined and modelled with help of variogram analysis. The resulting variogram models were
then used to calculate raster maps by applying ordinary kriging procedures. After intersecting these raster maps with punctual
data on eight benthic communities a decision tree was derived to predict the occurrence of these communities within the study
area. Since such a CART tree corresponds to a hierarchically ordered set of decision rules it was applied to the geostatistically
estimated raster data to predict benthic habitats within and near the EEZ. 相似文献
994.
Has-Schön E Bogut I Kralik G Bogut S Horvatić J Cacić M Cacić I 《Environmental monitoring and assessment》2008,144(1-3):15-22
Heavy metals concentration (mercury, lead, cadmium, arsenic, copper, zinc and chromium) in tissues (muscles, liver, kidney and gonads) of Dalmatian barbelgudgeon, the nase, the souffie and brown trout, inhabiting waters of Busko Blato reservoir in Bosnia and Herzegovina, has been determined by atomic absorption spectrophotometry. The meat of the tested fish sorts does not contain elevated concentration of most analyzed heavy metals with exception of lead (higher than MAC in Italy, Germany and Denmark) and mercury (in muscles of brown trout higher than MAC in most countries). The lowest level of all heavy metals is always detected in gonads, with higher values in fry compared to milt for copper, zinc, chromium and arsenic. The highest copper concentration is observed in the liver from the souffie which is suggested as a suitable biomonitor for copper intoxication. In muscles of all fish sorts, lead was always present in much higher concentration than cadmium, while in kidneys of most fish sorts, lead and cadmium concentrations were similar. We showed that bioaccumulation of some heavy metals in the fish sorts analyzed is tissue and sex dependent. Also, we concluded that the small water exchange in reversible shallow reservoir does not induce elevated concentration of heavy metals in fish tissues inhabiting Busko Blato. 相似文献
995.
Spanos T Simeonov V Simeonova P Apostolidou E Stratis J 《Environmental monitoring and assessment》2008,143(1-3):215-225
The environmetric data analysis of analytical datasets from sediment and benthic organisms samples collected from different sampling sites along the coast of Black Sea near to City of Varna, Bulgaria has given some important indications about the bioindication properties of both type of samples. Various multivariate statistical methods like cluster analysis, principal components analysis, source apportioning modeling and partial least square (PLS) modeling were used in order to classify and interpret the parameters describing the chemical content of the coastal sediments (major components, heavy metals and total organic carbon) and benthic organisms (heavy metals). It has been shown that seriously polluted coastal zones are indicated in the same way by all benthic species, although some specificity could be detected for moderate polluted regions' e.g. polychaeta accumulated preferably Co, Cr, Cu, and Pb; crustacea - As, Cd, and Ni; mollusca - Zn. The identified latent factors responsible for the dataset structure are clearly indicated and apportioned with respect to their contribution to the total mass or total concentration of the species in the samples. The linear regression and PLS models indicated that a reliable forecast about the relation between naturally occurring chemical components and polluting species accumulated in the benthic organisms is possible. 相似文献
996.
Dioxins like various gaseous pollutants and aerosols can be scavenged by appropriate vegetative greenbelts. Based on their stomatal properties and the models for contaminant uptake, uptake of dioxin (2,3,7,8-TCDD) by three important Indian plant species, viz. Eugenia jambolana (Jamun), Azadirachta indica (Neem) and Ficus religiosa (Peepal), has been estimated. 2,3,7,8-TCDD is a contaminant with severe harmful ecological ramifications. Computations show that Ficus religiosa has highest uptake capacity. The present exercise has its utility in designing appropriate green-belts for mitigating adverse environmental and human health impacts due to dioxins. This can be an effective management option for mitigating the damages caused by dioxins. 相似文献
997.
A simplified model for reservoir operation considering the water quality issues: Application of the Young conflict resolution theory 总被引:2,自引:0,他引:2
In this study, an algorithm combining a multi-objective genetic algorithm (GA)-based optimization model and a water quality simulation model is developed for determining a trade-off curve between objectives related to the allocated water quantity and quality. To reduce the run-time of the GA-based optimization model, the main problem is decomposed to long-term and annual optimization models. The reliability of water supply is considered to be the objective function in the long-term stochastic optimization model, but the objective functions of the annual models are related to both the allocated water quantity and quality. The operating policies obtained using this long-term model provide the time series of the optimum reservoir water storages at the beginning and the end of each water year. In the next step, these optimal reservoir storage values are considered as constraints for water storage in the annual reservoir operation optimization models. The epsilon-constraint method is then used to develop a trade-off curve between the reliability of water supply and the average allocated water quality. The Young conflict resolution theory, which incorporates the existing conflicts among decision-makers and stakeholders, is used for selecting the best solution on the trade-off curve. The monthly reservoir operating rules are then calculated using an Adaptive Neuro-Fuzzy Inference System, which is trained using the optimal operating policies. The proposed model is applied to the 15-Khordad Reservoir in the central part of Iran. The results show that this simplified procedure does not reduce the accuracy of the reservoir operating policies and it can effectively reduce the computational burden of the previously developed models. 相似文献
998.
Collivignarelli C Tharnpoophasiam P Vaccari M De Felice V Di Bella V Mingkwan R 《Environmental monitoring and assessment》2008,147(1-3):191-198
University of Brescia and Mahidol University of Bangkok developed a project in Phang Nga province (Thailand), the most damaged by 2004 tsunami. In particular, the study, performed between April and May 2006, dealt with the surface and ground water monitoring in Ban Nam Khem village and the experimental evaluation of possible drinking treatment alternatives. The monitoring highlighted that saline content in the tsunami affected area is decreasing but still very high (conductivity presented values up to 2,600 and 6,230 microS/cm in ground and surface water, respectively); hence, advanced and complicated processes such as reverse osmosis should be adopted to treat such water for drinking purposes. Waiting for ground water salinity to assume acceptable values, activities for the reduction of its organic and microbiological contamination will be started. However, it has to be underlined that the diffusion of drinking water to a greater part of population can be obtained only through the realization of new centralised treatment plants and the improvement of existing ones (serving at the moment about 20% of inhabitants). 相似文献
999.
Vanderstraeten P Lénelle Y Meurrens A Carati D Brenig L Offer ZY Zaady E 《Environmental monitoring and assessment》2008,146(1-3):33-39
The main objective of our research was to compare the airborne particle micromorphology and chemistry in the Brussels environment during agriculture working periods in the surrounding farming region. We used specific methods and instrumentation that are adapted to the climate peculiarities of the Brussels region, the period of investigations (12 months) and the proposed objectives. For the agricultural works we defined the following six periods: before sowing, sowing, after sowing, before harvest, harvest and after harvest. The results indicate a possible temporal correlation between agricultural work periods and airborne particle concentration, micromorphology and chemistry in the Brabant-Brussels region. For wheat and corn plant-growth periods, the average particle size, defined as the area obtained by a planar projection of the particulate, showed important variations in time. For sugar beet and endive, the average area size variations are less important. The roughness and sphericity parameters for the growth periods of the four different plants also showed significant differences. Many of the larger particulates (> 10 microm) are aggregates of even finer particles coated with many still finer ones. The airborne particle chemistry averages (atomic percentage At%), showed that three constituents (Si, S and Fe) dominate all the samples (except for particles 3-10 microm in size, which contain a relatively large percentage of Al). Applying similar investigation methods to study the correlations between airborne particle dynamics in urban zones and the agriculture working periods in their surrounding regions could be of interest to better understand the complexity of the PM problematic. 相似文献
1000.
Cozzi F Adami G Barbieri P Reisenhofer E Bovenzi M 《Environmental monitoring and assessment》2008,144(1-3):389-401
The aim of this study was to measure the concentration of some metals (Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Ti) in PM(10) samples collected in one urban and one industrial site and to assess that PM(10) total mass measurement may be not sufficient as air quality index due to its complex composition. Metals were determined by inductively coupled plasma-atomic emission spectroscopy (ICP-AES) and differential pulsed anodic stripping voltammetry (DPASV). The measured concentrations were used to calculate the content of metals in the PM(10) total mass, and to estimate the enrichment factors and the correlations between PM(10), metal concentrations and meteorological data for the two sites. The mean PM10 concentration during the sampling period in the urban site exceeded the annual European Union (EU) standard (40 microg/m(3)) and, for some sampling days, the daily EU standard (50 microg/m(3)) was also exceeded. In opposite, both EU standards were never exceeded in the industrial site. The overall metal content was nearly double in the industrial site compared to the urban one, and the mean Ni concentration exceeded the EU annual limit value (10 ng/m(3)). The metals with the highest enrichment factor were Cd, Cu, Ni and Pb for both sites, suggesting a dominant anthropogenic source for these metals. Metal concentrations were very low and typical of rural background during Christmas holidays, when factories were closed. PM(10) total mass measurement is not a sufficient air quality index since the metal content of PM(10) is not related to its total mass, especially in sites with industrial activities. This measurement should be associated with the analysis of toxic metals. 相似文献