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81.
Assessment and spatial distribution of groundwater quality in industrial areas of Ghaziabad, India 总被引:2,自引:0,他引:2
Savita Kumari Anil Kumar Singh Ashok Kumar Verma N. P. S. Yaduvanshi 《Environmental monitoring and assessment》2014,186(1):501-514
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
82.
Jadhav U Kadu S Thokal N Padul M Dawkar V Chougale A Salve A Patil M 《Environmental science and pollution research international》2011,18(7):1129-1138
Background, aim, and scope
The focus of the present study is to know the potential of bacterial isolate for tannic acid degradation at low temperature. Also, we tried to evaluate the suitability of phytotoxicity testing protocol for the determination of tannic acid toxicity. 相似文献83.
T. K. M. Prashantha Kumar Trivene R. Mandlimath P. Sangeetha S. K. Revathi S. K. Ashok Kumar 《Environmental Chemistry Letters》2018,16(2):389-400
Excessive nitrogen (N) and phosphorous (P) release into run-off waters from human activities is a major cause of eutrophication. Several techniques are available to remove N and P-containing pollutants, such as chemical precipitation, biological treatment, membrane processes, electrolytic treatment, ion-exchange and adsorption. In order to remove low concentration levels of nitrate and phosphate, adsorption is a cost-effective solution. In this review, we present a list of nanoscale adsorbents such as zero-valent metal, metal oxides/metal hydroxides, and carbon-based materials. We discuss their adsorption capacities, isotherms, kinetics and mechanisms. 相似文献
84.
Michael D. Sohn Pamela Reynolds Navtej Singh Ashok J. Gadgil 《Journal of the Air & Waste Management Association (1995)》2013,63(12):1422-1432
Abstract Releases of airborne contaminants in or near a building can lead to significant human exposures unless prompt response measures are taken. However, possible responses can include conflicting strategies, such as shutting the ventilation system off versus running it in a purge mode or having occupants evacuate versus sheltering in place. The proper choice depends in part on knowing the source locations, the amounts released, and the likely future dispersion routes of the pollutants. We present an approach that estimates this information in real time. It applies Bayesian statistics to interpret measurements of airborne pollutant concentrations from multiple sensors placed in the building and computes best estimates and uncertainties of the release conditions. The algorithm is fast, capable of continuously updating the estimates as measurements stream in from sensors. We demonstrate the approach using a hypothetical pollutant release in a five-room building. Unknowns to the interpretation algorithm include location, duration, and strength of the source, and some building and weather conditions. Two sensor sampling plans and three levels of data quality are examined. Data interpretation in all examples is rapid; however, locating and characterizing the source with high probability depends on the amount and quality of data and the sampling plan. 相似文献
85.
S. Paramasivam K. Jayaraman Takela C. Wilson Ashok K. Alva Luma Kelson Leandra B. Jones 《Journal of environmental science and health. Part. B》2013,48(3):317-324
Ammonia (NH3) emission from livestock manures used in agriculture reduces N uptake by crops and negatively impacts air quality. This laboratory study was conducted to evaluate NH3emission from different livestock manures applied to two soils: Candler fins sand (CFS; light-textured soil, pH 6.8 and field capacity soil water content of 70 g kg? 1) from Lake Alfred, Florida and Ogeechee loamy sand (OLS; medium-textured soil, pH 5.2 and field capacity soil water content of 140 g kg? 1) from Savannah, Georgia. Poultry litter (PL) collected from a poultry farm near Douglas, Georgia, and fresh solid separate of swine manure (SM) collected from a farm near Clinton, North Carolina were used. Each of the soil was weighed in 100 g sub samples and amended with either PL or SM at rates equivalent to either 0, 2.24, 5.60, 11.20, or 22.40 Mg ha? 1 in 1L Mason jars and incubated in the laboratory at field capacity soil water content for 19 days to monitor NH3 volatilization. Results indicated a greater NH3 loss from soils amended with SM compared to that with PL. The cumulative NH3volatilization loss over 19 days ranged from 4 to 27% and 14 to 32% of total N applied as PL and SM, respectively. Volatilization of NH3 was greater from light-textured CFS than that from medium-textured OLS. Volatilization loss increased with increasing rates of manure application. Ammonia volatilization was lower at night time than that during the day time. Differences in major factors such as soil water content, temperature, soil type and live stock manure type influenced the diurnal variation in volatilization loss of NH3 from soils. A significant portion (> 50%) of cumulative NH3 emission over 19 d occurred during the first 5–7 d following the application of livestock manures. Results of this study demonstrate that application of low rates of livestock manure (≤ 5.60 Mg ha? 1) is recommended to minimize NH3 emissions. 相似文献
86.
Ashok Kumar 《Journal of the Air & Waste Management Association (1995)》2013,63(8):827-832
Production from the world’s largest tar sands plant began in July 1978. Under the permit to construct the plant, Syncrude Canada Ltd. is permitted to emit 287 long tons of SO2/day as long as Alberta’s Clean Air Regulations are not Violated. In order to predict such violations for emission control purposes, it is important to know the diurnal variation of the thermal boundary layer (TBL) height. In this paper, a numerical model for the prediction of TBL height as a function of time of day is given based on the solution of appropriate conservation equations relating both the heat flux and the temperature jump across the inversion layer to the height of the TBL. The resulting equations are solved by the Runge-Kutta method. The model is tested against the field data collected as part of a base-line data acquisition program. A comparison is also made of two different methods (kink method and conventional method) to calculate thermal boundary heights from the mini-sonde data. Problems in the use of the results of TBL heights using these two methods for predicting pollution potential near the plant are also discussed. 相似文献
87.
Monitoring Long-Term Ecological Changes Through the Ecological Monitoring and Assessment Network: Science-Based and Policy Relevant 总被引:2,自引:0,他引:2
Ecological monitoring and its associated research programshave often provided answers to various environmental management issues. In the face of changing environmental conditions, ecological monitoring provides decision-makers with reliable information as they grapple with maintaining a sustainable economy and healthy environment. The EcologicalMonitoring and Assessment Network (EMAN) is a national ecological monitoring network consisting of (1) about 100 casestudy sites across the country characterized by long-term multi-disciplinary environmental work conducted by a multitudeof agencies (142 partners and counting); (2) a variety of lesscomprehensive yet more extensive monitoring sites; (3) a network where core monitoring variables of ecosystem change aremeasured; and (4) geo-referenced environmental observations. Environment Canada is the co-ordinating partner for the network through the EMAN Co-ordinating Office. EMAN's mission is to focus a scientifically-sound, policy-relevant ecosystem monitoring and research network based on (a) stabilizing a network of case-study sites operated by a varietyof partners, and (b) developing a number of cooperative dispersedmonitoring initiatives in order to deliver unique and needed goods and services. These goods and services include: (1) an efficient and cost-effective early warning system which detects,describes and reports on changes in Canadian ecosystems at a national or ecozone scale; and (2) cross-disciplinary and cross-jurisdictional assessments of ecosystem status, trends and processes. The early warning system and assessments of ecosystem status, trends and processes provide Environment Canada and partner organizations with timely information thatfacilitates increasingly adaptive policies and priority setting. Canadians are also informed of changes and trends occurring in Canadian ecosystems and, as a result, are betterable to make decisions related to conservation and sustainability. 相似文献
88.
Abhilash Vijayan Ashok Kumar 《Atmospheric environment (Oxford, England : 1994)》2010,44(34):4209-4218
This paper presents results from an in-vehicle air quality study of public transit buses in Toledo, Ohio, involving continuous monitoring, and experimental and statistical analyses to understand in-vehicle particulate matter (PM) behavior inside buses operating on B20-grade biodiesel fuel. The study also focused on evaluating the effects of vehicle’s fuel type, operating periods, operation status, passenger counts, traffic conditions, and the seasonal and meteorological variation on particulates with aerodynamic diameter less than 1 micron (PM1.0). The study found that the average PM1.0 mass concentrations in B20-grade biodiesel-fueled bus compartments were approximately 15 μg m?3, while PM2.5 and PM10 concentration averages were approximately 19 μg m?3 and 37 μg m?3, respectively. It was also observed that average hourly concentration trends of PM1.0 and PM2.5 followed a “μ-shaped” pattern during transit hours.Experimental analyses revealed that the in-vehicle PM1.0 mass concentrations were higher inside diesel-fueled buses (10.0–71.0 μg m?3 with a mean of 31.8 μg m?3) as compared to biodiesel buses (3.3–33.5 μg m?3 with a mean of 15.3 μg m?3) when the windows were kept open. Vehicle idling conditions and open door status were found to facilitate smaller particle concentrations inside the cabin, while closed door facilitated larger particle concentrations suggesting that smaller particles were originating outside the vehicle and larger particles were formed within the cabin, potentially from passenger activity. The study also found that PM1.0 mass concentrations at the back of bus compartment (5.7–39.1 μg m?3 with a mean of 28.3 μg m?3) were higher than the concentrations in the front (5.7–25.9 μg m?3 with a mean of 21.9 μg m?3), and the mass concentrations inside the bus compartment were generally 30–70% lower than the just-outside concentrations. Further, bus route, window position, and time of day were found to affect the in-vehicle PM concentrations significantly. Overall, the in-vehicle PM1.0 concentrations inside the buses operating on B20-grade biodiesel ranged from 0.7 μg m?3 to 243 μg m?3, with a median of 11.6 μg m?3.Statistical models developed to study the effects of vehicle operation and ambient conditions on in-vehicle PM concentrations suggested that while open door status was the most important influencing variable for finer particles and higher passenger activity resulted in higher coarse particles concentrations inside the vehicle compartments, ambient PM concentrations contributed to all PM fractions inside the bus irrespective of particle size. 相似文献
89.
The pot experiments were conducted to evaluate the effect of different concentrations of arsenic, chromium and zinc contaminated soils, amended with biosludge and biofertilizer on the growth of Jatropha curcas which is a biodiesel crop. The results further showed that biosludge alone and in combination with biofertilizer significantly improved the survival rates and enhanced the growth of the plant. With the amendments, the plant was able to grow and survive upto 500, 250 and 4,000 mg kg(-1) of As, Cr and Zn contaminated soils, respectively. The results also showed that zinc enhanced the growth of J. curcas more as compared to other metals contaminated soils. The heavy metal accumulation in plant increased with increasing concentrations of heavy metals in soil, where as a significant reduction in the metal uptake in plant was observed, when amended with biosludge and biofertilizer and biosludge alone. It seems that the organic matter present in the biosludge acted as metal chelator thereby reducing the toxicity of metals to the plant. Findings suggest that plantation of J. curcas may be promoted in metal contaminated soils, degraded soils or wasteland suitably after amending with organic waste. 相似文献
90.
Kumar S Dagar SS Mohanty AK Sirohi SK Puniya M Kuhad RC Sangu KP Griffith GW Puniya AK 《Die Naturwissenschaften》2011,98(6):457-472
Methanogens, the members of domain Archaea are potent contributors in global warming. Being confined to the strict anaerobic environment, their direct cultivation as
pure culture is quite difficult. Therefore, a range of culture-independent methods have been developed to investigate their
numbers, substrate uptake patterns, and identification in complex microbial communities. Unlike other approaches, fluorescence
in situ hybridization (FISH) is not only used for faster quantification and accurate identification but also to reveal the
physiological properties and spatiotemporal dynamics of methanogens in their natural environment. Aside from the methodological
aspects and application of FISH, this review also focuses on culture-dependent and -independent techniques employed in enumerating
methanogens along with associated problems. In addition, the combination of FISH with micro-autoradiography that could also
be an important tool in investigating the activities of methanogens is also discussed. 相似文献