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91.
The biologically treated distillery effluent (BTDE) contains intense colour, high total dissolved solids (TDS), chemical oxygen demand (COD) and biochemical oxygen demand (BOD). These properties even after primary, secondary and tertiary treatments contain high concentrations of TDS, COD and BOD. The paper highlights the safe disposal and treatment of BTDE on land through High Rate Transpiration System (HRTS). HRTS is a zero discharge, low cost, high-tech method for improving the quality of BTDE for potential reuse. The experiments conducted at bench and pilot scale showed that HRTS having coconut husk as a bedding material could successfully treat the BTDE with a hydraulic load of 200 m3 ha−1 day−1 having BOD of 100 mg l−1 and 500 m3 ha−1 day−1 having BOD of 500 mg l−1 with average COD load of 0.686 and 2.88 ton ha−1 day−1 during the post and pre monsoon periods respectively. There was no significant increase in the organic carbon of the soil irrigated with BTDE. The concentrations of various pollutants analyzed in the leachate were within the prescribed limit for the drinking water sources. The colour removal was 99 to 100% and BOD and COD were possible to treat with optimum hydraulic loading of BTDE through HRTS planted with Dendrocalamus strictus.  相似文献   
92.
Environmental Science and Pollution Research - Green vegetation improvement is an economical strategy to mitigate dust air pollution. The anticipated performance index (API) is considered a main...  相似文献   
93.
We investigated the possible drivers of the N:P stoichiometric shift and its relationship with micro-algal production of transparent exopolymeric particles (TEP) along a 35?km gradient of the Ganga River. The objective was to evaluate if the trade-off between N:P stoichiometry and production of TEP helps in maintaining water quality of the river. Mesocosm experiments were conducted to examine N:P-TEP linkages and its role in turbidity removal. In situ measurements did not show Si to be a limiting nutrient (N:Si?Aulacosira granulata and Fragilaria intermedia. Settling efficiency, turbidity removal and sedimentation of TEP, biogenic silica (BSi) and biomass all increased with decreasing N:P ratio proportionately to the amount of TEP produced in the mesocosm. The study demonstrates that trade-off between N:P stoichiometry and the production of TEP generates feedback to buffer the ecological impacts of nutrient pollution.  相似文献   
94.
This paper provides baseline information about the total annual dust fall, and its constituents and seasonal variation, from a sub-tropical opencast coalmine area in Bina, India. Dust samples were collected monthly for 2 years (June 2002-May 2004) from five sampling sites in the region and analyzed in the laboratory for water-soluble and -insoluble matter. Water-insoluble components constituted the major fraction of the total annual dust fall. Two-way ANOVA indicated significant variations in dust fall at different sites, over the months and in their interactions. The dust deposition rate was highest during summer (March-June), followed by winter (November-February) and lowest in the rainy season (July-October). Maximum dust fall was observed near the coal handling plant (at site 2) followed by the receiving pit of the coal handling plant (site 3), near the main sub-station (site 4), Jawahar colony (site 1) and Gharasari village (site 5). An inverse and significant relation was observed between dust fall and precipitation. Our studies have shown that the main residential areas are experiencing higher levels of dust fall which makes them unsuitable for living. We suggest that residential areas should be moved farther away from the mining area in the opposite direction of prevalent winds.  相似文献   
95.
Samples were collected every 2-4 weeks from a set of 37 monitoring wells over a period of 2-3 years in Araihazar, Bangladesh, to evaluate the temporal variability of groundwater composition for As and other constituents. The monitoring wells are grouped in 6 nests and span the 5-91 m depth range. Concentrations of As, Ca, Fe, K, Mg, Mn, Na, P, and S were measured by high-resolution ICPMS with a precision of 5% or better; concentrations of Cl were measured by ion chromatography. In shallow wells <30 m deep, As and P concentrations generally varied by <30%, whereas concentrations of the major ions (Na, K, Mg, Ca and Cl) and the redox-sensitive elements (Fe, Mn, and S) varied over time by up to +/-90%. In wells tapping the deeper aquifers >30 m often below clay layers concentrations of groundwater As were much lower and varied by <10%. The concentrations of major cations also varied by <10% in these deep aquifers. In contrast, the concentration of redox-sensitive constituents Fe, S, and Mn in deep aquifers varied by up to 97% over time. Thus, strong decoupling between variations in As and Fe concentrations is evident in groundwaters from shallow and deep aquifers. Comparison of the time series data with groundwater ages determined by (3)H/(3)He and (14)C dating shows that large seasonal or inter-annual variations in major cation and chloride concentrations are restricted to shallow aquifers and groundwater recharged <5 years ago. There is no corresponding change in As concentrations despite having significant variations of redox sensitive constituents in these very young waters. This is attributed to chemical buffering due to rapid equilibrium between solute and solid As. At two sites where the As content of groundwater in existing shallow wells averages 102 microg/L (range: <5 to 648 microg/L; n=118) and 272 microg/L (range: 10 to 485 microg/L; n=65), respectively, a systematic long-term decline in As concentrations lends support to the notion that flushing may slowly deplete an aquifer of As. Shallow aquifer water with >5 years (3)H/(3)He age show a constant As:P molar ratio of 9.6 over time, suggesting common mechanisms of mobilization.  相似文献   
96.
Kumar A  Pandey AK  Singh SS  Shanker R  Dhawan A 《Chemosphere》2011,83(8):1124-1132
Extensive production and consumption of nanomaterials such as ZnO and TiO2 has increased their release and disposal into the environment. The accumulation of nanoparticles (NPs) in ecosystem is likely to pose threat to non-specific targets such as bacteria. The present study explored the effect of ZnO and TiO2 NPs in a model bacterium, Salmonella typhimurium. The uptake of ZnO and TiO2 bare NPs in nano range without agglomeration was observed in S. typhimurium. TEM analysis demonstrated the internalization and uniform distribution of NPs inside the cells. Flow cytometry data also demonstrates that both ZnO and TiO2 NPs were significantly internalized in the S. typhimurium cells in a concentration dependent manner. A significant increase in uptake was observed in the S. typhimurium treated even with 8 and 80 ng mL−1 of ZnO and TiO2 NPs with S9 after 60 min, possibly the formation of micelles or protein coat facilitated entry of NPs. These NPs exhibited weak mutagenic potential in S. typhimurium strains TA98, TA1537 and Escherichia coli (WP2uvrA) of Ames test underscoring the possible carcinogenic potential similar to certain mutagenic chemicals. Our study reiterates the need for re-evaluating environmental toxicity of ZnO and TiO2 NPs presumably considered safe in environment.  相似文献   
97.
Environmental Chemistry Letters - The continuous growth of the world population has raised heatlh&nbsp;issues such as the inefficiency of common drugs, such as antibiotics, due to...  相似文献   
98.
99.
People perceive places differently because of the different material, social, and symbolic aspects of the locations and because individuals have different backgrounds and different reasons for being at the locations. Two studies examined how role and religious beliefs affect perceptions of the environment at the Magh Mela, an annual religious festival at the confluence of the Ganges and Yamuna Rivers in north India. In the first study (n=375), we interviewed individuals who were at the Mela for one of six reasons (religious pilgrims, sweepers, boatmen, police, businessmen, or student volunteers) about their religious beliefs and their perceptions of the Mela. Results indicated that the evaluations of pilgrims, who were at the Mela for religious reasons, were associated with evaluations of physical amenities and religious social support, whereas the other five groups, who were at the Mela primarily for nonreligious purposes, evaluated the Mela on the basis of material characteristics only. In the second study (n=311), we found that religious leaders’ evaluations of the Mela were affected by material characteristics, religious social support, and intrinsic religious belief.  相似文献   
100.
In the present communication habitat ecology, species diversity; distribution and different indices of fish biodiversity management were studied in a Central India river (River Betwa, a tributary of River Ganga basin approved under India’s first river linking plan). Correlation between fish species richness with the hydrological attributes showed good relationship and water depth, dissolved oxygen and pH were found the most important variables in shaping fish assemblage. Altogether, sixty-three fish species belonging to 20 families and 45 genera were collected from five sampling stations spread along the upstream, mid stream and lower streams. Cyprinids were the most dominated group represented by 26 species belonging to 15 genera, followed by Bagridae (6 species from 3 genera), and Schilbeidae (4 species from 4 genera). The distribution of fish showed interesting pattern and about 10% species were common to all the sites showing long migration range. Shannon-Weiner diversity index showed considerable variation and ranged from 1.89 to 3.51. Out of 63 species status of 10 species were not known due to data deficit, 29 categorized as lower risk, 14 as vulnerable, 8 as endangered, while the remaining two species were introduced. Our study shows that the River supports considerable diversity of the fishes and is important for conservation and about 34% fish fauna is threatened being either vulnerable or endangered. We assessed that the river supports considerable percentage of food fish (89.47), ornamental fish (49.12%) and sport fish (5.26%). Among the eight major types of fish habitats identified along the entire stretch of river, open river, shallow water and deep pools were habitats contributing maximum diversity. Fish species richness (FSR) were significantly different (P < 0.05) in all the habitats except channel confluence and scour pool. Trophic niche model may be useful for assessing altered as well as less altered fish habitat of the tropical rivers. Since this river will be interlinked in near future, this study would be useful for conservation planning and management and also for future assessment after interlinking. Issues related to various threats to aquatic environment and conservation management strategies have been discussed.  相似文献   
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