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91.
Chromium is a pollutant present in electroplating waste water and its removal is necessary for the protection of the environment. Vetiveria zizanioides (VZ) was grown in chromium effluent concentrations of 50, 100 and 200 mg kg ?1 soil amended with organic manure and the potential for phytoremediation was determined. The amounts of Cr in plant tissues (root and shoot), soil and percentage electrolyte leakage of VZ roots were analysed. From the results, VZ amended with organic manure showed the greatest potential for Cr removal because of its faster growth and larger biomass achieved over the whole length of the experiment. In this study, 92.25% Cr removal efficiency was obtained with a Cr concentration of 50 mg kg ?1 soil and removal efficiencies of 90.5% and 85% were obtained with 100 and 200 mg kg?1, respectively after a period of two months of VZ growth.  相似文献   
92.
The present investigation reports the effect of repeated (90 days) administration of carbendazim on the biochemical and hematological parameters in male goats. Carbendazim administered orally at a daily dose of 50 mg kg?1 body weight for 90 consecutive days resulted in increased plasma concentration of aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH), gamma-glutamyl transferase (GGT), creatinine and albumin, while alkaline phosphatase (ALP) and glucose levels were decreased. Decrease in total leukocyte (TLC) and neutrophil count and increase in lymphocyte count was observed in the treatment group. The findings of the present investigation indicate that sub-chronic exposure to carbendazim in male goats causes hepatic and slight kidney dysfunctions.  相似文献   
93.
The various indigenous uses and structure of chir pine forests were studied in Uttaranchal state of the Indian Republic. A questionnaire survey was conducted in 50 villages of Uttaranchal to gather information on the indigenous uses of chir pine. For the study of community composition and structure of chir pine forest, at least 15 quadrats of 10 x 10 m were selected randomly across various localities, and the number of individuals, along with other dominant tree and shrub species, were enumerated in each quadrat. About 10 indigenous uses of chir pine were prominent in Uttaranchal. Besides resin, an important non-wood product, different parts of chir pine, such as cones, trunk, stems, wood, leaves and bark, were used by the local people. Chir pine is a subject of the folklore and mythology of indigenous cultures in Uttaranchal. Chir pine forest formed three major communities in Uttaranchal viz., sal-pine (Shorea robusta-Pinus roxburghii), pine pure stands and oak-pine (Quercus leucho-trichophora-Pinus roxburghii). These communities sustained various multiple-use trees and shrubs along with various edible mushrooms (eg. Agaricus campestris, Morchella esculenta and Sparassis crispa). The results of this study are discussed in the light of chir pine conservation and management policies.  相似文献   
94.
ABSTRACT: A convenient method for the statistical analysis of hydrologic extremes is to use probability papers to fit selected theoretical distributions to extremal observations. Three commonly accepted statistical distributions of extreme hydrologic events are: the double exponential distribution, the bounded exponential distribution, and the Log Pearson Type III distribution. In most cases, probability papers are distribution specific. But, for the Log Pearson Type III distribution, the probability paper is characterized by a population-specific parameter, namely, the coefficient of skewness. It is not practicable to procure probability papers for all possible values of this parameter. Therefore, a computer program is developed to generate population-specific probability papers and to perform statistical analysis of the data using computer graphics. Probability papers covering return periods up to 1000 years or more are generated for the three distributions mentioned above. Using a plot routine, available extremal observations are plotted on selected probability papers and a linear regression analysis is used to fit a straight line to the data. Predictions of hydrologic extremes for higher recurrence intervals can be made by extrapolating the fitted straight lines.  相似文献   
95.
Environmental Science and Pollution Research - The major global concern on energy is focused on conventional fossil resources. The burning of fossil fuels is an origin of greenhouse gas emissions...  相似文献   
96.
A study was conducted in the residential areas of Delhi, India, to assess the variation in ambient air quality and ambient noise levels during pre-Diwali month (DM), Diwali day (DD) and post-Diwali month during the period 2006 to 2008. The use of fireworks during DD showed 1.3 to 4.0 times increase in concentration of respirable particulate matter (PM10) and 1.6 to 2.5 times increase in concentration of total suspended particulate matter (TSP) than the concentration during DM. There was a significant increase in sulfur dioxide (SO2) concentration but the concentration of nitrogen dioxide (NO2) did not show any considerable variation. Ambient noise level were 1.2 to 1.3 times higher than normal day. The study also showed a strong correlation between PM10 and TSP (R 2 ≥ 0.9) and SO2 and NO2 (R 2 ≥ 0.9) on DD. The correlation between noise level and gaseous pollutant were moderate (R 2 ≥ 0.5). The average concentration of the pollutants during DD was found higher in 2007 which could be due to adverse meteorological conditions. The statistical interpretation of data indicated that the celebration of Diwali festival affects the ambient air and noise quality. The study would provide public awareness about the health risks associated with the celebrations of Diwali festival so as to take proper precautions.  相似文献   
97.
This study compares speciated model-predicted concentrations (i.e., mixing ratios) of volatile organic compounds (VOCs) with measurements from the Photochemical Assessment Monitoring Stations (PAMS) network at sites within the northeastern US during June–August of 2006. Measurements of total non-methane organic compounds (NMOC), ozone (O3), oxides of nitrogen (NOx) and reactive nitrogen species (NOy) are used for supporting analysis. The measured VOC species were grouped into the surrogate classes used by the Carbon Bond IV (CB4) chemical mechanism. It was found that the model typically over-predicted all the CB4 VOC species, except isoprene, which might be linked to overestimated emissions. Even with over-predictions in the CB4 VOC species, model performance for daily maximum O3 was typically within ±15%. Analysis at an urban site in NY, where both NMOC and NOx data were available, suggested that the reasonable ozone performance may be possibly due to compensating overestimated NOx concentrations, thus modulating the NMOC/NOx ratio to be in similar ranges as that of observations.  相似文献   
98.
The study aimed at determining the socio-economic issues due to municipal solid waste dumping, the extent of groundwater contamination and the groundwater dependency around Perungudi dumpsite in Tamil Nadu, India. Sampling and analysis of groundwater and leachate show the contamination migration is due to dumpsite leachate. The concentrations of contaminants were more severe within 1.5?km along groundwater flow direction mainly due to the geological profile. The Piper diagram also shows that the groundwater sampled within 3?km in the flow direction was classified as Na–Cl type. Studies conducted within contaminated areas to determine the groundwater usage showed that higher percentage of lower and middle socio-economic status categories was using the groundwater for domestic purposes, which may lead to health issues. The present study suggests that proper solid waste management and groundwater remediation techniques along with the people’s involvement are necessary to reduce the consequences of groundwater contamination on the people residing around the dumpsite.  相似文献   
99.
In this study, the effect of silver nanoparticles and silver ions on Arabidopsis thaliana was investigated at physiological and molecular levels. The seedlings were grown in sublethal concentrations of silver nanoparticles and silver ions (0.2, 0.5, and 1 mg/L) in 1/4 Hoagland’s medium for 14 days under submerged hydroponic conditions. Significantly higher reduction in the total chlorophyll and increase in anthocyanin content were observed after exposure to 0.5 and 1 mg/L silver nanoparticles as compared to similar concentrations of silver ions. Lipid peroxidation increased significantly after exposure to 0.2, 0.5, and 1 mg/L of silver nanoparticles and 0.5 and 1 mg/L of silver ions. Qualitative analysis with dichloro-dihydro-fluorescein diacetate and rhodamine 123 fluorescence showed a dose-dependent increase in reactive oxygen species production and changes in mitochondrial membrane potential in the roots of seedlings exposed to different concentrations of silver nanoparticles. Real-time PCR analysis showed significant upregulation in the expression of sulfur assimilation, glutathione biosynthesis, glutathione S-transferase, and glutathione reductase genes upon exposure to silver nanoparticles as compared with silver ions. Overall, based on the physiological and molecular level responses, it was observed that exposure to silver nanoparticles exerted more toxic response than silver ions in A. thaliana.  相似文献   
100.
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