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Precipitation samples collected during 2005–2009 from a rural forest station of Bhubaneswar were analyzed for their chemical composition. The samples were collected through a wet-only (WO) collector and two bulk (B1 and B2) collectors. The ions were evenly balanced indicating good data quality. The overall pH of rainwater was slightly acidic and ~47% of all rain events during the period were acidic (pH?<?5.6). Multilinear regression analysis showed relation between the free acidity (H+) and other components in rainwater. Enrichment factors (EF) of the major components with respect to their sources such as marine and crustal were calculated. Maximum EF was observed for NO 3 ? for both marine and crustal sources for all the three collectors. Source apportionments were also carried for the ions. Trend analysis showed continuous increase in most of the ions over years during the study period driven by anthropogenic emissions. Statistical/factorial analysis established correlation among different ions.  相似文献   
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The sudden release of a quantity of gas into the atmospheric boundary layer produces a contaminant cloud. The expected mass fraction function provides a relatively simple measure of the contaminant concentration values found within the cloud and represents the ensemble-averaged fraction of the conserved release mass found at the different contaminant concentration intervals as the cloud evolves. The plume generated by a line source in grid turbulence is used to investigate the expected mass fraction function as it applies to scalar concentration values found on a typical line normal to the plume axis. Simultaneous particle image velocimetry and planar laser induced fluorescence are used to measure velocity and concentration fields, respectively. The measured expected mass fraction functions are observed to be approximately self-similar when concentration values are normalized by the centreline mean concentration. The moments of the expected mass fraction function are observed to be simply related to the centreline moments of the probability density function of scalar concentration. Arguments based on a source fluid, non-source fluid decomposition of the scalar probability density function are used to explain these observations. The results are compared with the theoretical and experimental results established for a line source of scalar in grid turbulence.  相似文献   
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The carbonaceous chondrites are intriguing and unique in the sense that they are the only rocks that provide pristine records of the early solar nebular processes. We report here results of a detailed mineralogical, chemical, amino acid and isotopic studies of a recently observed fall at Mukundpura, near Jaipur in Rajasthan, India. Abundance of olivines in this meteorite is low and of serpentine minerals is high. FeO/SiO_2 = 1.05 in its Poorly Characterized Phases(PCP) is similar to that observed in other CM2.0 chondrites. The water content of ~9.8 wt.% is similar to that found in many other CM chondrites.Microscopic examination of matrix shows that its terrestrial weathering grade is WO but aqueous parent body alteration is high, as reflected in low abundance of identifiable chondrules and abundant remnants of chondrules(~7%). Thus, most of the chondrules formed initially have been significantly altered or dissolved by aqueous alterations on their parent bodies. The measured bulk carbon(2.3%) and nitrogen content and their isotopic(δ13C =-5.5‰, δ15N = 23.6%0) composition is consistent with CM2.0 classification probably bordering CM1. Several amino acids such as Alanine, Serine, Proline, Valine, Threonine,Leucine, Isoleucine, Asparagine and Histamine are present. Tyrosine and Tryptophan may occur in trace amounts which could not be precisely determined. All these data show that Mukundpura chondrite lies at the boundary of CM2.0 and CM1 type carbonaceous chondrites making it one of the most primitive chondrites.  相似文献   
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Uttarakhand state in India is well known for its mountainous ecosystems,traditional communities and a variety of ecotourism destinations.Among various tourism activities,River Rafting along the banks of the Ganges River has increased tremendously for two decades,and has had unprecedented impacts on the traditional communities and the bio-diversity.Therefore,it is meaningful to do a comprehensive study on the various impacts associated with river rafting so as to suggest the pathways to achieve the environmental sustainability in this region.In this study,we collected primary data from randomly selected population units across all stake holders such as local people(n = 100),and camp personnel(n = 22),through a pre-tested questionnaire survey between August 2009 and May 2010.The questionnaire contains issues on culture,social,economic,institutional and associated perceived impacts on pollution and biodiversity including views for sustainability.Secondary information was also collected from various sources and government records to supplement and strengthen the analysis.The impacts were analyzed qualitatively through a ranking mechanism to facilitate the decision making process.The perception of the interviewee about the various possible impacts of rafting was discussed with mitigating mechanism.The ranking analysis as percollected data reveals that economy and education of local community was improved significantly;however aquatic and terrestrial fauna,social cohesion and pollution(water,air,land) were significantly deteriorated.The results show that the existing practices are not sufficient to address the adverse impacts.Improvement in practices is necessary,mainly in the policy regime.Based on the analysis,some measures are recommended on how to protect community interest and environment with the development of river rafting as an ecotourism opportunity.  相似文献   
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Abstract

Estimation of snowmelt runoff is very important in the Western Himalayan rivers in India where it is required to plan for hydropower generation and the water management during the non‐monsoon season. An attempt has been made to estimate snowmelt runoff on a 10 day average basis in Beas Basin up to Pandoh Dam during May, 1998 and November, 1999 using a Snowmelt Runoff Model (SRM), which is a degree day method. The input parameters for the model are derived from existing maps, satellite data, metrological and hydrological data. The relief of the basin is divided into 12 elevation zones of 500 m each. The temperature was extrapolated to these elevation zones using temperature lapse rate calculated using the observed temperature at seven stations within the basin. Snow covered area in the basin was determined using Indian Remote Sensing Satellites IRS ‐ 1C / 1D Wide Field Sensor (WIFS). The runoff from the snow covered area and snow free area was separately calculated in each elevation zone. The model parameter degree‐day factor is taken from literature and runoff coefficients for snow and rain are derived using the observed data. The total discharge at the dam site is computed by a weighted sum of runoff components from all the elevation zones. There is a good agreement between the observed and computed runoff with a coefficient of determination of 0.854 and the difference in volume is + 4.6 %.  相似文献   
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As a catchment phenomenon, land use and land cover change (LULCC) has a great role in influencing the hydrological cycle. In this study, decadal LULC maps of 1985, 1995, 2005 and predicted-2025 of the Subarnarekha, Brahmani, Baitarani, Mahanadi and Nagavali River basins of eastern India were analyzed in the framework of the variable infiltration capacity (VIC) macro scale hydrologic model to estimate their relative consequences. The model simulation showed a decrease in ET with 0.0276% during 1985–1995, but a slight increase with 0.0097% during 1995–2005. Conversely, runoff and base flow showed an overall increasing trend with 0.0319 and 0.0041% respectively during 1985–1995. In response to the predicted LULC in 2025, the VIC model simulation estimated reduction of ET with 0.0851% with an increase of runoff by 0.051%. Among the vegetation parameters, leaf area index (LAI) emerged as the most sensitive one to alter the simulated water balance. LULC alterations via deforestation, urbanization, cropland expansions led to reduced canopy cover for interception and transpiration that in turn contributed to overall decrease in ET and increase in runoff and base flow. This study reiterates changes in the hydrology due to LULCC, thereby providing useful inputs for integrated water resources management in the principle of sustained ecology.  相似文献   
8.
Acid- and water-soluble component of suspended particulate matter was studied from January 2009 to December 2009 at Bhubaneshwar, an urban coastal location of eastern India, by high-volume sampler, environmental dust monitor using GRIMM®, and scanning electron microscope and energy dispersive X-ray spectrometer. The water-soluble components accounted for 30–45 % of the total suspended particulate matter, and the major elements were observed to be ammonium and nitrate as the cationic and anionic species, respectively. The acid-soluble component like copper, nickel, cobalt, iron, and lead accounted for 5–15 % of the total particulate matter concentration. The composition of particulate matter shows a clear seasonal variation in relation to wind speed, wind direction, and trajectories of the air mass movement. The GRIMM spectrometer analysis shows higher concentration of fine particulate matter. Source apportionment and enrichment factor analysis indicated that except sodium and chloride, all other elements have emerged from different sources such as crustal as well as anthropogenic.  相似文献   
9.
The potentialities of satellite remote sensing for acquiring informations useful for forest management have already been recognised. The analysis of satellite data can provide reconnaissance survey maps showing the spatial distribution of forest type and other useful information of the existing forest resources in the area in very short time. The present study has been carried out in Godavari river Basin, Nallamalai and Seshachalam hiil ranges, which are potential areas for Teak, bamboo and red-sanders respectively. The three Landsat scenes have been analysed using Multispectral Data Analysis System (M-Das) to make maps on 1:250,000 scale. The Computer classified colour coded maps show the spatial distribution of the industrially important species and association with other forest types existing in the area. The results have been discussed in the context of using Landsat data for reconnaissance survey of forest resources at a national level.  相似文献   
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