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541.
Singh K Singh DP Dixit CK Singh N Sharma C Sahai S Jha AK Kumari M Khan ZH Gupta PK 《Environmental monitoring and assessment》2012,184(7):4553-4564
A field campaign on aerosol chemical properties and trace gases measurements was carried out along the Delhi-Hyderabad-Delhi road corridor (spanning about 3,200 km) in India, during February 1-29, 2004. Aerosol particles were collected on quartz and cellulose filters using high volume (PM(10)) sampler at various locations along the route (i.e., urban, semi-urban, rural, and forest areas) and have been characterized for major cations (Na(+), Ca(2+), Mg(2+), K(+), and NH (4) (+)), anions (Cl(-), NO (3)(-), and SO (4)(2-)), and heavy metals (Cu, Cd, Fe, Zn, Mn, and Pb). Simultaneously, we measured NO(2) and SO(2) gases. These species show large spatial and temporal variations. The ambient PM(10) concentration has been observed to be the highest (55 ± 4 μg m(-3)) near semi-urban areas followed by forest areas (48 ± 2 μg m(-3)) and in rural areas (44 ± 22 μg m(-3)). The concentrations of NO( x ) (NO(2)+NO) and SO(2) ranged from 16 to 69 μg m(-3) and 4 to 11 μg m(-3), respectively. Among anions, NO(3)(-) and SO(4) (2-) are the major constituents of PM(10). The urban and semi-urban sites showed enhanced concentrations of Fe, Zn, Mn, Cd, and Pb. This study provide information about atmospheric concentrations of various species in the northern to central India, which may be important for policy makers to better understand the air quality of the region. 相似文献
542.
Chauhan VS Yunus M Sankararamakrishnan N 《Environmental monitoring and assessment》2012,184(8):4889-4901
The level of arsenic (As) contamination and the geochemical composition of groundwater in Shuklaganj area located on the banks of the Ganges Delta of Kanpur-Unnao district were elucidated. Samples (n?=?59) were collected from both India Mark II hand pumps (depth, 30-33 m) and domestic hand pump tube wells (10-12 m) located within 5 km from the banks of Ganges. Samples were analyzed for various parameters, including total inorganic As, sulfate, nitrate, alkalinity, ammonia, and iron. Hydrochemistry of the groundwater aquifer was studied through the trilinear plots between monovalent and divalent cations and anions. In Indian mark II hand pumps, arsenic concentration ranged from below detection limit to 448 μg/L. Most of the samples contained both As(III) and As(V). The pH of the samples ranged from 7.1 to 8.2. Except for a few, most of the samples were reducing in nature as evident by their negative oxidation reduction potentials. A positive correlation for arsenic with iron, ammonia, and dissolved organic carbon shows the probability of biodegradation of organic matter and reductive dissolution of Fe oxyhydroxide processes to leach As in aquifers. For confirmation of the suggested arsenic mobilization mechanism, the presence and absence of sulfate-reducing bacteria and iron-reducing bacteria were also tested. 相似文献
543.
This paper presents the implementation of a Geospatial approach for improving the Municipal Solid Waste (MSW) disposal suitability
site assessment in growing urban environment. The increasing trend of population growth and the absolute amounts of waste
disposed of worldwide have increased substantially reflecting changes in consumption patterns, consequently worldwide. MSW
is now a bigger problem than ever. Despite an increase in alternative techniques for disposing of waste, land-filling remains
the primary means. In this context, the pressures and requirements placed on decision makers dealing with land-filling by
government and society have increased, as they now have to make decisions taking into considerations environmental safety
and economic practicality. The waste disposed by the municipal corporation in the Bhagalpur City (India) is thought to be
different from the landfill waste where clearly scientific criterion for locating suitable disposal sites does not seem to
exist. The location of disposal sites of Bhagalpur City represents the unconsciousness about the environmental and public
health hazards arising from disposing of waste in improper location. Concerning about urban environment and health aspects
of people, a good method of waste management and appropriate technologies needed for urban area of Bhagalpur city to improve
this trend using Multi Criteria Geographical Information System and Remote Sensing for selection of suitable disposal sites.
The purpose of GIS was to perform process to part restricted to highly suitable land followed by using chosen criteria. GIS
modeling with overlay operation has been used to find the suitability site for MSW. 相似文献
544.
Hydrochemical analysis to evaluate the seawater ingress in a small coral island of India 总被引:1,自引:0,他引:1
Banerjee P Singh VS Singh A Prasad RK Rangarajan R 《Environmental monitoring and assessment》2012,184(6):3929-3942
The sustainable development of the limited groundwater resources in the tropical island requires a thorough understanding
of detail hydrogeological regime including the hydrochemical behavior of groundwater. Detail analysis of chemical data of
groundwater helps in assessing the different groundwater zone affected by formation as well as sea water. Groundwater and
saline water interaction is better understood using groundwater major ion chemistry over an island aquifer. Multivariate methods
to analyze the geochemical data are used to understand geochemical evolution of groundwater. The methods are successfully
used to group the data to evaluate influence of various environs in the study area. Various classification methods such as
piper, correlation method, and salinity hazard measurements are also employed to critical study of geochemical characteristics
of groundwater to identify vulnerable parts of the aquifer. These approaches have been used to successfully evaluate the aquifer
zones of a tiny island off the west coast of India. The most part of island is found to be safe for drinking, however some
parts of island are identified that are affected by sea water ingress and dissolution of formation minerals. The analysis
has successfully leaded to identification of that part of aquifer on the island which needs immediate attention for restoration
and avoids further deterioration. 相似文献
545.
Dey RK Swain SK Mishra S Sharma P Patnaik T Singh VK Dehury BN Jha U Patel RK 《Environmental monitoring and assessment》2012,184(5):3279-3291
The present investigation reports the assessment of hydrochemical/geochemical processes controlling the concentration of fluoride
in groundwater of a village in India (Boden block, Orissa). Boden block is one of the severely affected fluoride-contaminated
areas in the state of Orissa (India). The sampling and subsequent analysis of water samples of the study area was carried
out following standard prescribed methods. The results of the analysis indicate that 36.60% groundwater F− concentration exceeds the limit prescribed by the World Health Organization for drinking water. The rock interaction with
groundwater containing high concentration of HCO3− and Na+ at a higher pH value of the medium could be one of the important reasons for the release of F− from the aquatic matrix into groundwater. Geochemical classification of groundwater based on Chadha rectangular diagram shows
that most of the groundwater samples having fluoride concentration more than 1.5 mg L−1 belongs to the Na-K-HCO3 type. The saturation index values evaluated for the groundwater of the study area indicated that it is oversaturated with
respect to calcite, whereas the same is undersaturated with respect to fluorite content. The deficiency of calcium ion concentration
in the groundwater from calcite precipitation favors fluorite dissolution leading to excess of fluoride concentration. The
risk index was calculated as a function of fluoride level in drinking water and morbidity of fluorosis categorizes high risk
for villages of Amera and Karlakote panchayat of Boden block. 相似文献
546.
547.
Wazir Singh Lakra Uttam Kumar Sarkar Rupali Sani Kumar Ajay Pandey Vineet Kumar Dubey Om Prakash Gusain 《The Environmentalist》2010,30(4):306-319
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
548.
Spatial Variability of Groundwater Depth and Quality Parameters in the National Capital Territory of Delhi 总被引:3,自引:0,他引:3
The groundwater quantity and quality scenario is of much concern in the National Capital Territory of Delhi, India, which
necessitates an investigation to envisage the extent of spatial variability of groundwater depth and pollutant concentration
levels in this region. Therefore, in this study, an effort was made to generate the spatial variability map of groundwater
depth and quality parameters (viz. chloride, electrical conductivity, fluoride, magnesium, and nitrate). Ordinary kriging
was used to analyze the spatial variability of groundwater depth and quality parameters, whereas indicator kriging was used
to analyze groundwater quality parameters equal to or greater than the pollution threshold values. It was observed that the
semivariogram parameters fitted well in the exponential model for water depth and in the spherical model for water quality
parameters. The generated spatial variability maps indicated that in 43% of the study area, groundwater depth was within 20 m.
The salinity level was higher than 2.5 dS m−1 in 69% of the study area and the nitrate concentration exceeded 45 mg l−1 in 36% of the area. The probability maps showed that about 24% of the area had the highest probability (0.8–1.0) of exceedence
of the threshold electrical conductivity value and an area of 2% exhibited the highest probability of exceedence of the threshold
value of nitrate concentration in the groundwater. The generated spatial variability and probability maps will assist water
resource managers and policymakers in development of guidelines in judicious management of groundwater resources for agricultural
and drinking purposes in the study area. 相似文献
549.
550.
High bat (Chiroptera) diversity in the Early Eocene of India 总被引:1,自引:0,他引:1
Smith T Rana RS Missiaen P Rose KD Sahni A Singh H Singh L 《Die Naturwissenschaften》2007,94(12):1003-1009
The geographic origin of bats is still unknown, and fossils of earliest bats are rare and poorly diversified, with, maybe,
the exception of Europe. The earliest bats are recorded from the Early Eocene of North America, Europe, North Africa and Australia
where they seem to appear suddenly and simultaneously. Until now, the oldest record in Asia was from the Middle Eocene. In
this paper, we report the discovery of the oldest bat fauna of Asia dating from the Early Eocene of the Cambay Formation at
Vastan Lignite Mine in Western India. The fossil taxa are described on the basis of well-preserved fragments of dentaries
and lower teeth. The fauna is highly diversified and is represented by seven species belonging to seven genera and at least
four families. Two genera and five species are new. Three species exhibit very primitive dental characters, whereas four others
indicate more advanced states. Unexpectedly, this fauna presents strong affinities with the European faunas from the French
Paris Basin and the German Messel locality. This could result from the limited fossil record of bats in Asia, but could also
suggest new palaeobiogeographic scenarios involving the relative position of India during the Early Eocene. 相似文献