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Nitin Patil Vishnu Prakash Reddy Anurag Patangray Surendra Kumar Singh 《Arabian Journal of Geosciences》2018,11(1):8
Groundwater is the most important source of water in meeting irrigation, drinking, and other needs in India. The assessment of the potential zone for its recharge is critical for sustainable usage, quality management, and food security. This study reports alternative mapping of the groundwater recharge potential of a selected block by including large-scale soil data. Thematic layers of soil, geomorphology, slope, land use land cover, topographical wetness index, and drainage density of Darwha block (District Yavatmal, Maharashtra, India) were generated and integrated in a geographic information system environment. The topographic maps, thematic maps, field data, and satellite image were processed, classified, and weighted using analytical hierarchical process for their contribution to groundwater recharge. The layers were integrated by weighted linear combination method in the GIS environment to generate four groundwater potential zones viz., “poor,” “poor to moderate,” “moderate to high,” and “high.” Based on the generated groundwater potential map, about 9830 ha (12%) of the study area was categorized as high potential for recharge, 25,558 ha (31%) as poor to moderate, 33,398 ha (40%) as moderate to high, and 12,565 ha (15%) as poor potential zone. The zonation corresponds well with the field data on greater well density (0.22/ha) and irrigated crop area (27%) in the high potential zone as against 0.02 wells/ha and only 6% irrigated area in the poor zone. The map is recommended for use in regulating groundwater development decisions and judicious expenditure on drilling new wells by farmers and the state authorities. 相似文献
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Accurate interatomic potentials have been employed to compute the phonon density of states of αquartz, stishovite and coesite polymorphs of silica. The temperature variation of several thermodynamic properties is calculated by using the phonon density of states to describe the vibrational entropy contribution to the free energy. Results for these polymorphs are in surprisingly good agreement with available experimental data. Moreover, the microscopic origin of quantitative differences in the heat capacity behavior of low and high density polymorphs is established. 相似文献
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Interpretation of Slug Test Data 总被引：2，自引：0，他引：2
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With trends indicating increase in temperature and decrease in winter precipitation, a significant negative trend in snow-covered areas has been identified in the last decade in the Himalayas. This requires a quantitative analysis of the snow cover in the higher Himalayas. In this study, a nonlinear autoregressive exogenous model, an artificial neural network （ANN）, was deployed to predict the snow cover in the Kaligandaki river basin for the next 30 years. Observed climatic data, and snow covered area was used to train and test the model that captures the gross features of snow under the current climate scenario. The range of the likely effects of climate change on seasonal snow was assessed in the Himalayas using downscaled temperature and precipitation change projection from - HadCM3, a global circulation model to project future climate scenario, under the AIB emission scenario, which describes a future world of very rapid economic growth with balance use between fossil and non-fossil energy sources. The results show that there is a reduction of 9% to 46% of snow cover in different elevation zones during the considered time period, i.e., 2Oll to 2040. The 4700 m to 52oo m elevation zone is the most affected area and the area higher than 5200 m is the least affected. Overall, however, it is clear from the analysis that seasonal snow in the Kaligandaki basin is likely to be subject to substantialchanges due to the impact of climate change. 相似文献
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We have presented the localization of kinetic Alfvén wave (KAW) in intermediate β plasma (m e /m i ?β?1) by developing a model based on pump kinetic Alfvén wave and finite amplitude magnetosonic fluctuations. When KAW is perturbed by these background magnetosonic fluctuations, filamentary structures of KAW magnetic field are formed. First, a semi analytical model based on paraxial approximation has been developed to understand this evolution process. Localized structures and magnetic fluctuation spectrum of KAW has also been studied numerically for finite frequency of KAW. The calculated magnetic fluctuation spectrum follows two types of scalings. Above the proton gyroradius scale lengths (in inertial range), spectrum follows Kolmogorovian scaling. Below this scale dispersion starts and the spectrum steepens to about \(k_{x}^{-2.5}\) . The result shows the steepening of power spectra which can be responsible for particle acceleration in solar wind due to the energy transfer from larger to smaller lengthscales. Obtained magnetic turbulent spectra are consistent with observations of Cluster spacecraft in solar wind. 相似文献
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Arti Thanki Hirendrasinh Padhiyar Nitin Kumar Singh Manish Yadav Johnson Christian 《洁净——土壤、空气、水》2023,51(3):2100336
Moringa oleifera (MO), also known as drumstick tree, has gained worldwide attention among researchers and policy makers, for showing its remarkable potential in environmental management. Recently, MO seed or press cake (a by-product of oil extraction industry) powder has also emerged as an alternative and promising coagulant for environmental remediation. In this view, attempts have been made in this study to evaluate the efficacy of MO seed and press cake powder (MSP & PCP) for the treatment of municipal wastewater. Both MSP and PCP are characterized by using swelling ratio, scanning and transmission electron microscopy analysis. The effect of various operational parameters such as coagulation–flocculation pH (2–10), coagulant dosage (0.1–1 g L−1), and sedimentation time (0–180 min), etc., is investigated to understand the potential of MSP and PCP. At optimized operational conditions, sedimentation kinetics is also performed suggesting that the treatment process is being governed by the second-order kinetic model. The chemical and biological oxygen demand removals at optimized conditions are observed as follows: ≈38 and ≈73% for MSP and ≈47 and ≈85% for PCP. Overall, the results of the present study elucidated that PCP can be employed as a promising alternative of MSP for municipal wastewater with improved treatment efficiencies. 相似文献
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Optimal design of rain gauge network in the Middle Yarra River catchment,Australia 总被引：1，自引：0，他引：1 
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下载免费PDF全文 Rainfall data are a fundamental input for effective planning, designing and operating of water resources projects. A well‐designed rain gauge network is capable of providing accurate estimates of necessary areal average and/or point rainfall estimates at any desired ungauged location in a catchment. Increasing network density with additional rain gauge stations has been the main underlying criterion in the past to reduce error and uncertainty in rainfall estimates. However, installing and operation of additional stations in a network involves large cost and manpower. Hence, the objective of this study is to design an optimal rain gauge network in the Middle Yarra River catchment in Victoria, Australia. The optimal positioning of additional stations as well as optimally relocating of existing redundant stations using the kriging‐based geostatistical approach was undertaken in this study. Reduction of kriging error was considered as an indicator for optimal spatial positioning of the stations. Daily rainfall records of 1997 (an El Niño year) and 2010 (a La Niña year) were used for the analysis. Ordinary kriging was applied for rainfall data interpolation to estimate the kriging error for the network. The results indicate that significant reduction in the kriging error can be achieved by the optimal spatial positioning of the additional as well as redundant stations. Thus, the obtained optimal rain gauge network is expected to be appropriate for providing high quality rainfall estimates over the catchment. The concept proposed in this study for optimal rain gauge network design through combined use of additional and redundant stations together is equally applicable to any other catchment. © 2014 The Authors. Hydrological Processes published by John Wiley & Sons Ltd. 相似文献
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Formation of atoll garnets in the UHP eclogites of the Tso Morari Complex,Ladakh, Himalaya 总被引：1，自引：0，他引：1
Mallika K Jonnalagadda Nitin R Karmalkar Raymond A Duraiswami Shivani Harshe Sarah Gain William L Griffin 《Journal of Earth System Science》2017,126(8):107
The eclogites of the Tso Morari Complex, Ladakh, NW Himalayas preserve both garnets with spectacular atoll textures, as well as whole porphyroblastic garnets. Whole garnets are euhedral, idiomorphic and enclose inclusions of amphibole, phengite and zoisite within the cores, and omphacite and quartz/coesite towards the rims. Detailed electron microprobe analyses and back-scattered electron images show well-preserved prograde zoning in the whole garnets with an increase in Mg and decrease in Ca and Mn contents from the core to the rim. The atoll garnets commonly consist of euhedral ring over island/peninsular core containing inclusions of phengite, omphacite and rarely amphibole between the core and ring. Compositional profiles across the studied atoll grains show elemental variations with higher concentrations of Ca and Mn with low Mg at the peninsula/island cores; contrary to this low Ca, Mn and high Mg is observed at the outer rings. Temperature estimates yield higher values at the Mg-rich atoll garnet outer rings compared to the atoll cores. Atoll garnet formation was favoured by infiltration of fluid formed due to breakdown of hydrous phases, and/or the release of structurally bounded OH from nominally anhydrous minerals at the onset of exhumation. Infiltration of fluids along pre-existing fracture pathways and along mineral inclusion boundaries triggered breakdown of the original garnet cores and released elements which were subsequently incorporated into the newly-grown garnet rings. This breakdown of garnet cores and inward re-growth at the outer ring produced the atoll structure. Calibrated geo-thermobarometers and mineral equilibria reflect that the Tso Morari eclogites attain peak pressures prior to peak temperatures representing a clockwise path of evolution. 相似文献
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Abstract Upper Lake is the lifeline of Bhopal City, India for drinking and other water needs. In recent years, environmentalists have expressed their serious concern on deteriorating water quality of this lake. Conventional field sampling methods for monitoring lake water quality lack spatial information about the pollution in the lake. It is desirable to have spatial information about the lake for better management and control. In the present paper the remote sensing data from IRS-1C LISS III have been integrated into a GIS environment to analyse and create a pollution zone map of the Upper Lake. Spectral reflectance analysis was carried out to find the suitability of wavelengths for determining chlorophyll‐a concentration (chl‐a), suspended solid concentration (SSC) and secchi depth (SD). Empirical models relating spectral reflectance and chl‐a, SSC and SD were developed using least square regression analysis. These models were found valid on unused samples. Chl‐a, SSC and SD distribution maps were generated using proposed models and were incorporated as datalayers in the GIS for further analysis of pollution zones. The spatial information of pollution offered by the pollution zone map could delineate regions of lake having high pollution load. The methodology employed in this work can be used for regular monitoring of the pollution in surface water bodies and serve the data needs for better management of the water quality. 相似文献