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91.

With the boom in industrialization, there is an increase in the level of heavy metals in the soil which drastically affect the growth and development of plants. Nickel is an essential micronutrient for plant growth and development, but elevated level of Ni causes stunted growth, chlorosis, nutrient imbalance, and alterations in the defense mechanism of plants in terms of accumulation of osmolytes or change in enzyme activities like guiacol peroxidase (POD), catalase (CAT), and superoxide dismutase (SOD). Ni-induced toxic response was studied in seedlings of finger millet, pearl millet, and oats in terms of seedling growth, lipid peroxidation, total chlorophyll, proline content, and enzymatic activities. On the basis of germination and growth parameters of the seedling, finger millet was found to be the most tolerant. Nickel accumulation was markedly lower in the shoots as compared to the roots, which was the highest in finger millet and the lowest in shoots of oats. Plants treated with a high concentration of Ni showed significant reduction in chlorophyll and increase in proline content. Considerable difference in level of malondialdehyde (MDA) content and activity of antioxidative enzymes indicates generation of redox imbalance in plants due to Ni-induced stress. Elevated activities of POD and SOD were observed with high concentrations of Ni while CAT activity was found to be reduced. It was observed that finger millet has higher capability to maintain homeostasis by keeping the balance between accumulation and ROS scavenging system than pearl millet and oats. The data provide insight into the physiological and biochemical changes in plants adapted to survive in Ni-rich environment. This study will help in selecting the more suitable crop species to be grown on Ni-rich soils.

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92.
An attempt has been made in this study to evaluate the groundwater quality in two industrial blocks of Ghaziabad district. Groundwater samples were collected from shallow wells, deep wells and hand pumps of two heavily industrialized blocks, namely Bulandshahar road industrial area and Meerut road industrial area in Ghaziabad district for assessing their suitability for various uses. Samples were collected from 30 sites in each block before and after monsoon. They were analyzed for a total of 23 elements, namely, Ag, Al, As, B, Ba, Be, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, P, Pb, Se, U, V, and Zn. In addition to these elements, some other parameters were also studied viz: color, odor, turbidity, biological oxygen demand, chemical oxygen demand (COD), dissolved oxygen, total dissolved solids and total suspended solid. The water quality index was also calculated based on some of the parameters estimated. Out of the 23 elements, the mean values of 12 elements, namely, Al, As, Ca, Cd, Cr, Mg, Mn, Na, Ni, Pb, Se, and U, were higher than the prescribed standard limits. The concentrations (in milligram per liter) of highly toxic metals viz., Al, As, Cd, Cr, Ni, Pb, Se, and U, ranged from 1.33–6.30, 0.04–0.54, 0.005–0.013, 4.51–7.09, 0.14–0.27, 0.13–0.32, 0.16–2.11, and 0.10–1.21, respectively, in all groundwater samples, while the permissible limits of these elements as per WHO/BIS standards for drinking are 0.2, 0.01, 0.003, 0.05, 0.07, 0.01, 0.04, and 0.03 mg L?1, respectively. The EC, pH, and COD in all samples varied from 0.74–4.21, 6.05–7.72, and 4.5–20.0 while their permissible limits are 0.7 dS m?1, 6.5–8.5, and 10 mg L?1, respectively. On the basis of the above-mentioned parameters, the water quality index of all groundwater samples ranged from 101 to 491, and 871 to 2904 with mean value of 265 and 1,174 based on two criteria, i.e., physico-chemical and metal contaminations, respectively while the prescribed safe limit for drinking is below 50. The results revealed that the groundwater in the two blocks is unfit for drinking as per WHO/BIS guidelines. The presence of elements like As, Se, and U in toxic amounts is a matter of serious concern.  相似文献   
93.
We analysed aerosol optical and physical properties in an urban environment (Kolkata) during winter monsoon pollution transport from nearby and far-off regions. Prevailing meteorological conditions, viz. low temperature and wind speed, and a strong downdraft of air mass, indicated weak dispersion and inhibition of vertical mixing of aerosols. Spectral features of WinMon aerosol optical depth (AOD) showed larger variability (0.68–1.13) in monthly mean AOD at short-wavelength (SW) channels (0.34–0.5 μm) compared to that (0.28–0.37) at long-wavelength (LW) channels (0.87–1.02 μm), thereby indicating sensitivity of WinMon AOD to fine aerosol constituents and the predominant contribution from fine aerosol constituents to WinMon AOD. WinMon AOD at 0.5 μm (AOD 0. 5) and Angstrom parameter ( α) were 0.68–0.82 and 1.14–1.32, respectively, with their highest value in December. Consistent with inference from spectral features of AOD, surface aerosol loading was primarily constituted of fine aerosols (size 0.23–3 μm) which was 60–70 % of aerosol 10- μm (size 0.23–10 μm) concentration. Three distinct modes of aerosol distribution were obtained, with the highest WinMon concentration at a mass median diameter (MMD) of 0.3 μm during December, thereby indicating characteristics of primary contribution related to anthropogenic pollutants that were inferred to be mostly due to contribution from air mass originating in nearby region having predominant emissions from biofuel and fossil fuel combustion. A relatively higher contribution from aerosols in the upper atmospheric layers than at the surface to WinMon AOD was inferred during February compared to other months and was attributed to predominant contribution from open burning emissions arising from nearby and far-off regions. A comparison of ground-based measurements with Moderate Resolution Imaging Spectroradiometer (MODIS) data showed an underestimation of MODIS AOD and α values for most of the days. Discrepancy in relative distribution of fine and coarse mode of MODIS AOD was also inferred.  相似文献   
94.
Environmental Science and Pollution Research - Vanadium pentoxide can be an inexpensive replacement to vanadium sulfate in synthesizing vanadium redox flow battery (VRFB) electrolytes. In this...  相似文献   
95.
Environmental Science and Pollution Research - Inflammasome activity plays a vital role in various non-microbial disease states correlated with prolonged inflammation. NLRP3 inflammasome function...  相似文献   
96.
Most of freshwater bodies all over the world are becoming polluted, thus decreasing the portability of the water. In India religious practices have deep relationship with water bodies. They also patronized religious practices and constructed numerous relatively small water bodies along with temples throughout the country. Today, with the rapid pace of urban development, most of these water bodies have become sinks for waste discharge, resulting in deterioration of their water quality. Upper Lake of Bhopal, constructed in the eleventh century, is typical example of urban water bodies and a major source of potable water for the people of Bhopal. Till the middle of the last century, the water of Upper Lake did not require any treatment before supply for drinking purposes. Idol worship is common in India. Idols are usually made up of wood, bamboo, straw, jute ropes, clay, and plaster of Paris and are painted with bright synthetic colors, which often contain heavy metals. Other materials, such as straw, jute ropes, flowers, leaves and germinated grains cause short-term deterioration of water quality on their decay, while heavy metals in the paints pose health hazards in the long-run. Religious issues are extremely sensitive and hence it was felt necessary to use the regard that the citizens had for the lake to build a consensus in support of change. The Bhoj Wetland Project was implemented with the aid of Japanese Bank of International Cooperation (JBIC) to take action for preserving the Upper Lake of Bhopal (called Bhoj Wetlands). Our study is highlighted to water quality parameters like turbidity, total hardness, DO (Dissolved oxygen), BOD (Biochemical Oxygen Demand), COD (Chemical Oxygen Demand) and heavy metals in the year 1999 and 2005 i.e. before implementation of project and completion of project.  相似文献   
97.
In this study a new methodology is suggested to approximate the impact area downwind of an air pollution source, where air quality monitoring can be carried out to capture the maximum pollutant concentration. Hourly wind speed for a given month is grouped in to different wind speed ranges and the distance of pollutant travel is approximated from the average wind speed of that wind speed range. Since change in wind direction causes the impact distance to rotate, its rotation is approximated by the SD of wind direction change. Using this approach, area or region down wind of a source is determined and plotted. The pattern of monthly change of wind is better represented by the new type of diagram as compared to the wind rose diagram.  相似文献   
98.
The analyses presented in this paper include the concentration levels of NO2 and O3 measured during 2 successive years in twin cities (Rawalpindi and Islamabad) of Pakistan from November 2009 to March 2011. NO2 was determined using the passive sampling method, while ozone was determined by Model 400E ozone analyzer. The average NO2 and O3 concentration in twin cities of Pakistan was found to be 44?±?6 and 18.2?±?1.24 ppb, respectively. Results indicate that the concentration of NO2 and O3 show seasonal variations. Results also depict that NO2 and O3 concentration levels are high in areas of intense traffic flow and congestion. Rawalpindi has more elevated levels of NO2 and O3 as compared to the Islamabad due to the narrow roads, enclosing architecture of road network and congestion. Climatic variables also influenced the NO2 and O3 concentration, i.e., temperature is positively related with O3, while negatively related with NO2, relative humidity is directly related with NO2 and inversely related with O3, whereas rainfall show negative association with both NO2 and O3 concentration. Comparing the results with WHO standards reveals that NO2 concentration levels at all the sampling points are above the permissible limit, while ozone concentration is still lower than the WHO standards. Thus, there is a need to take appropriate steps to control these continuously increasing levels of NO2 and O3 before they become a serious hazard for the environment and people living in those areas.  相似文献   
99.
Observations on above ground litter decomposition and nutrient release in alpine ecosystem of the Himalaya were carried out. Monthly variation was observed for above ground litter crop and it was higher in the protected sites (PR) when compared with unprotected sites (UNPR). Turnover rate (TR) and time (TT) was also higher in PR sites and it corresponded to maximum net accumulation of standing dead and litter biomass. This resulted into low litter disappearance and therefore, low nutrient fluxes as well. Comparatively, potassium content was a maximum followed by N and OC in above ground crop of litter with significant variation among the sites (P < 0.001 and 0.005, respectively). It was observed that only 9–12% litter of various categories was decomposed annually at the rate of 0.1–0.13%. Overall, decomposition process was a maximum during active growth season and only 13.2–16.2% of total litter was decomposed during the winter months (December–March). Release of OC and NPK to soil organic matter through the decomposition of various litter types was also observed and the pattern of release was similar to that of disappearance channel. All these parameters are reported and possible reasons are described in the present paper.  相似文献   
100.
Humans are primarily exposed to fluoride (Fl), a widespread environmental pollutant, via contaminated drinking water and foodstuffs. The aim of this study was to examine whether sodium fluoride (NaF) exerted cytotoxic effects in human hepatocarcinoma (HepG2) cells. HepG2 cells were incubated with different concentrations of NaF and reactive oxygen species (ROS) levels, cell cycle, apoptosis, and DNA damage determined. Concentration-dependent studies showed that exposure to HepG2 cells with different concentrations of NaF for 24 hr significantly decreased cell viability and intracellular antioxidant capacity. Furthermore, NaF exposure increased lipid peroxidation levels and accumulation of intracellular ROS; and lowered antioxidant glutathione concentrations. In addition to oxidative impairments, NaF treatment enhanced HepG2 cell death via apoptotic pathway as evidenced by DNA fragmentation and cell cycle arrest. Sodium fluoride treatment unregulated p53 level, and Bax and Bcl2 expression. Diminished cell viability and changes in cell cycle accompanied a rise in p53 expression.  相似文献   
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