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941.
Auto-pollution is the by-product of our mechanized mobility, which adversely affects both plant and human life. However, plants growing in the urban locations provide a great respite to us from the brunt of auto-pollution by absorbing the pollutants at their foliar surface. Foliar surface configuration and biochemical changes in two selected plant species, namely Ficus religiosa L. and Thevetia nerifolia L., growing at IT crossing (highly polluted sites), Picup bhawan crossing (moderately polluted site) and Kukrail Forest Picnic Spot (Low polluted site) were investigated. It was observed that auto-exhaust pollution showed marked alterations in photosynthetic pigments, protein and cysteine contents and also in leaf area and foliar surface architecture of plants growing at HP site as compared to LP site. The changes in the foliar configuration reveal that these plants can be used as biomarkers of auto-pollution. 相似文献
942.
The concentration of uranium has been assessed in drinking water samples collected from different locations in Bathinda district,
Punjab, India. The water samples are taken from hand pumps and tube wells. Uranium is determined using fission track technique.
Uranium concentration in the water samples varies from 2.23± 0.05 to 87.05± 0.29 μg/L. These values are compared with safe
limit values recommended for drinking water. The uranium concentration in almost all drinking water samples is found to be
more than the safe limit. Analysis of some heavy metals viz. Zn, Cd, Pb and Cu in water is made. The concentration of sodium,
potassium, calcium, magnesium, chlorine and total hardness along with the pH value and conductivity of the water samples are
measured. Some of the samples show stunningly high values of these parameters. 相似文献
943.
Trace element concentration in groundwater of Pesarlanka Island, Krishna Delta, India 总被引:3,自引:0,他引:3
N. C. Mondal V. S. Singh S. C. Puranik V. P. Singh 《Environmental monitoring and assessment》2010,160(1-4):215-227
There is a growing concern over the potential accumulation of trace element concentration in groundwater of coastal aquifer owing seawater encroachment in the last several decades. A total of 29 groundwater samples collected from Pesarlanka Island, Krishna delta, Andhra Pradesh, India were analyzed for 13 trace elements (B, V, Mn, Fe, Ni, Co, Cu, Zn, As, Sr, Cd, Ba, and Pb) using inductively coupled plasma mass spectrometry. The results reveal that B, Fe, Ni, As, Sr, and Pb vary from 11.22 to 710.2, 1.25 to 684.6, 0.02 to 37.33, 27.8 to 282.3, 164.1 to 7,009, and 1.97 to 164.4 μg/l, respectively. Ba, Cd, Co, Cu, Ni, V, and Zn are almost within permissible limits for drinking water, but As, Fe, Mn, Pb, B, and Sr are above the permissible limit. The toxic element Pb is 1.64 times more than the maximum permissible limits of drinking water. The minimum value of As is also 2.78 times more, whereas the maximum is 28.2 times the permissible limit. The spatial distributions of alkaline earths (Sr, Ba), transition metals (V, Co, Ni, Fe), metallic elements (Cu, Pb), and (As) were found in considerable variation in the entire Island. Good cross-correlations were found between As, B, Co, and Sr with total dissolved solids and among other trace elements such as B, As, Co, and Sr. The variability observed within the groundwater samples is closely connected to the sea spray input; hence, it is primarily a consequence of geographical and meteorological factors, such as distance from the ocean and time of year. The trace element levels, in particular those of heavy metals, are very low, suggesting an origin from natural sources rather than from anthropogenic contamination. A few trace elements (Sr and B) are found as sensitive parameters responding to changes in fresh to saline groundwater environment. The highly elevated trace elements in this area which may be attributed to marine sediments or death and decay of plants are presented in this paper. 相似文献
944.
D. P. Singh Ranu Gadi T. K. Mandal C. K. Dixit Khem Singh T. Saud Nahar Singh Prabhat K. Gupta 《Environmental monitoring and assessment》2010,163(1-4):1-13
The variation in air quality was assessed from the ambient concentrations of various air pollutants [total suspended particle (TSP), particulate matter ≤10 μm (PM10), SO2, and NO2] for pre-Diwali, Diwali festival, post-Diwali, and foggy day (October, November, and December), Delhi (India), from 2002 to 2007. The extensive use of fireworks was found to be related to short-term variation in air quality. During the festival, TSP is almost of the same order as compared to the concentration at an industrial site in Delhi in all the years. However, the concentrations of PM10, SO2, and NO2 increased two to six times during the Diwali period when compared to the data reported for an industrial site. Similar trend was observed when the concentrations of pollutants were compared with values obtained for a typical foggy day each year in December. The levels of these pollutants observed during Diwali were found to be higher due to adverse meteorological conditions, i.e., decrease in 24 h average mixing height, temperature, and wind speed. The trend analysis shows that TSP, PM10, NO2, and SO2 concentration increased just before Diwali and reached to a maximum concentration on the day of the festival. The values gradually decreased after the festival. On Diwali day, 24-h values for TSP and PM10 in all the years from 2002 to 2007 and for NO2 in 2004 and 2007 were found to be higher than prescribed limits of National Ambient Air Quality Standards and exceptionally high (3.6 times) for PM10 in 2007. These results indicate that fireworks during the Diwali festival affected the ambient air quality adversely due to emission and accumulation of TSP, PM10, SO2, and NO2. 相似文献
945.
A. K. Nayak T. Damodaran C. S. Singh S. K. Jha D. Raja V. K. Mishra D. K. Sharma Gurbachan Singh 《Environmental monitoring and assessment》2010,170(1-4):185-193
A post tsunami study was conducted to assess the changes in soil properties in the Andaman Island, in India. The present study reported tsunami led conversion of acid soils to saline acid soils and acid sodic soils to acid saline sodic soils in the areas South Andaman inundated during tsunami and permanently receded later and in the low-lying area submerged during high tides. Upon intense leaching acid saline soils and acid saline sodic may further develop typical characteristics of acidic soils and acidic sodic soil, respectively. The soil at Guptapara inundated almost due to tsunami with minimal pyrite oxidation has potential to develop into highly acidic soils upon drainage. The tsunami by and large has modified some depositional layer affecting the salt accumulation to a greater extent and iron to a lesser extent and least to sodicity. 相似文献
946.
Passive monitoring of nitrogen dioxide in urban air: a case study of Durban metropolis, South Africa
To devise and implement strategies to manage the quality of urban air, a metropolis needs air pollution data on which an air quality management plan can be formulated. Although air pollutants can come from several sources, many reports suggest that nitrogen dioxide from motor vehicle emissions is the major contributor to air pollution in cities. Since vehicles stop or move slowly through traffic intersections, concentrations of nitrogen dioxide (NO(2)) are expected to be relatively high at these sites. Inexpensive Ogawa passive samplers were placed at selected traffic intersections in the Durban Metropolis to trap the NO(2) which was then analysed by a sensitive laboratory-based method. The data obtained by this method was compared with data from sophisticated system comprising an active sampler cum on-line chemiluminescence detector. The sampling was done over a twelve month period to cover all seasons. Statistical analysis of the data showed that there was no significant difference between the means for the two methods. This study has established that an Ogawa passive sampler may be used as an economical and reliable collector for NO(2) in ambient air under varying climatic conditions. Further, the analysis method using a UV-Visible spectrophotometer was sensitive enough to detect NO(2) at the 10-20 ppb level. The cost of the method should be well within the budgets of most municipalities and it would motivate them to develop policies to alleviate traffic congestion. 相似文献
947.
Sacred groves are well recognized in the world in terms of biodiversity conservation. The present study was conducted in the Nakuleshwar sacred grove, in the valley of Thal kedar hill in the Kumaon region of Pithoragarh district in Indian Himalaya, in appreciation of its role in biodiversity conservation. The study aimed at the documentation and inventory of the sacred grove, its phytodiversity, threats and conservation in the Himalayan region, and to achieve this, systematic field surveys were conducted during 2007?C2010 covering all four seasons. A total of 83 species from 71 genera and 50 families were identified, of which 43 species are flowering plants, including 7 trees, 7 shrubs, 4 climbers and 25 herbs, and 40 species are non-flowering plants of which lichens are represented by 12 species from 8 genera, bryophytes 6 species from 5 genera, and pteridophytes 7 species from 9 genera, while gymnosperms are represented by a single species. Acer oblongum, Cinnamomum tamala, Cedrus deodara, Coriaria nepalensis act as keystone species in the grove. Ophiopogon inermis is a common herb during the rainy season while Goodyera hemsleyana (Orchid) is a new distribution record for the western Himalaya. A total of 43 species from 38 genera are used ethnobotanically by local people for various ailments. Mahonia nepaulensis, Asparagus adscendens, Thalictrum foliolosum, Cinnamomum tamala and Berberis asiatica are highly exploited species and need to be conserved. Climatic conditions of the grove are moderate and the floristic patch of the grove is completely different from the plant diversity of the surrounding area and matches with the diversified floral wealth of comparatively higher altitudes. Due to anthropogenic pressure, this grove is facing new threats of degradation, hence needing special attention. 相似文献
948.
Singh SK Ramaiah N 《Journal of environmental biology / Academy of Environmental Biology, India》2011,32(3):339-346
Denaturing gradient gel electrophoresis (DGGE) was used to elucidate spatial and temporal variations in bacterial community composition (BCC) from four locations along the central west coast of India. DNA extracts from 36 water samples collected from surface, mid-depth (-10 m) and dose to bottom (-20 m) during premonsoon, postmonsoon, monsoon were analyzed by PCRfor amplifying variable region of 16S rRNAgene and subsequently through DGGE. Prominent bands were excised, cloned and sequenced indicated the preponderance of gammaproteobacteria, bacteroidetes and cyanobacteria. Non-metric dimensional scaling of the DGGE gels indicated that the spatial variations in BCC were prominent among the sampling locations. Temporal variations in the BCC appear to be influenced by monsoonal processes. The canonical correspondence analyses suggest that the concentration of chlorophyll a and nitrate are two important environmental factors for both spatial and temporal variations in BCC. Chlorophyll a seems to be impart a top-down control of BCC while nitrate, the bottom-up control. Our results also suggest that BCC can vary over a small geographic distance in highly dynamic, seasonally predisposed tropical coastal waters. 相似文献
949.
Meena PD Chattopadhyay C Kumar A Awasthi RP Singh R Kaur S Thomas L Goyal P Chand P 《Journal of environmental biology / Academy of Environmental Biology, India》2011,32(3):375-379
High severity of Altemaria blight disease is a major constraint in production of rapeseed-mustard in India. The aim of this study was to investigate the suppressive potential of chemicals viz., zinc sulphate, borax, sulphur, potash and calcium sulphate, aqueous extracts viz., Eucalyptus globosus (50 g l-1) leaf extract and garlic (Allium sativum) bulb (20 g l-1) extract, cow urine and bio-agents Trichoderma harzianum, Pseudomonas fluorescence in comparison with the recommended chemical fungicide (mancozeb), against foliar disease Alternaria blight of Indian mustard [Brassica juncea (L.) Czern. and Coss] under five different geographical locations of India. Mancozeb recorded the lowest mean severity (leaf: 33.1%; pod: 26.3%) of Alternaria blight with efficacy of garlic bulb extract alone (leaf = 34.4%; pod = 27.3%) or in combination with cow urine (leaf = 34.2%; pod = 28.6%) being statistically at par with the recommended chemical fungicide. Chemicals also proved effective in reducing Alternaria blight severity on leaves and pods of Indian mustard (leaf = 36.3-37.9%; pod = 27.5-30.1%). The effective treatments besides providing significant reduction in disease severity also enabled increase in dry seed yield of the crop (mancozeb = 2052 kg ha-1; garlic = 2006 kg ha-1; control = 1561 kg ha-1). 相似文献
950.
A study was conducted to evaluate the water quality of Jaipur City. Groundwater samples from hand pumps and tube wells of eleven sampling stations were analyzed during monsoon session with the help of standard methods of APHA. The analytical results shows higher concentration of total dissolved solids, electrical conductivity, total hardness and nitrate, which indicate signs of deterioration but values of pH, calcium, magnesium, sulphate and fluoride are within permissible limit as per WHO standards. From the Hill-Piper trilinear diagram, it is observed that the majority of ground water from sampling stations are calcium-magnesium-chloride-sulphate type water. The values of sodium absorption ratio and electrical conductivity of the ground water were plotted in the US salinity laboratory diagram for irrigation water. Most of the samples fall in C3S1 quality with high salinity hazard and low sodium hazard. Chemical analysis of groundwater shows that mean concentration of cation (in meq/l) is in order magnesium > sodium > calcium > potassium while for the anion (in meq/l) it is chloride > bicarbonate > sulphate > nitrate > carbonate > fluoride. 相似文献