Numerical groundwater-flow modeling to evaluate potential effects of pumping and recharge: implications for sustainable groundwater management in the Mahanadi delta region,India   总被引：1，自引：0，他引：1  

Sasmita Sahoo  Madan K. Jha 《Hydrogeology Journal》2017,25(8):2489-2511

Process-based groundwater models are useful to understand complex aquifer systems and make predictions about their response to hydrological changes. A conceptual model for evaluating responses to environmental changes is presented, considering the hydrogeologic framework, flow processes, aquifer hydraulic properties, boundary conditions, and sources and sinks of the groundwater system. Based on this conceptual model, a quasi-three-dimensional transient groundwater flow model was designed using MODFLOW to simulate the groundwater system of Mahanadi River delta, eastern India. The model was constructed in the context of an upper unconfined aquifer and lower confined aquifer, separated by an aquitard. Hydraulic heads of 13 shallow wells and 11 deep wells were used to calibrate transient groundwater conditions during 1997–2006, followed by validation (2007–2011). The aquifer and aquitard hydraulic properties were obtained by pumping tests and were calibrated along with the rainfall recharge. The statistical and graphical performance indicators suggested a reasonably good simulation of groundwater flow over the study area. Sensitivity analysis revealed that groundwater level is most sensitive to the hydraulic conductivities of both the aquifers, followed by vertical hydraulic conductivity of the confining layer. The calibrated model was then employed to explore groundwater-flow dynamics in response to changes in pumping and recharge conditions. The simulation results indicate that pumping has a substantial effect on the confined aquifer flow regime as compared to the unconfined aquifer. The results and insights from this study have important implications for other regional groundwater modeling studies, especially in multi-layered aquifer systems.  相似文献   

A multilinear discrete Nash-cascade model for stage-hydrograph routing in compound river channels     

Bhabagrahi Sahoo  Muthiah Perumal  Tommaso Moramarco  Silvia Barbetta  Soumyaranjan Sahoo 《水文科学杂志》2020,65(3):335-347

ABSTRACT

Stream gauge-based information is the foundation for many hydrological applications in a river basin including the aquatic-habitat conservation. A simple two-parameter model for routing streamflow depth (alternatively, stream–stage) hydrographs and estimating corresponding discharge hydrographs in river channels is proposed using the multilinear approach, based on Nash-type discrete-cascade model. The applicability of this model is investigated by extending its framework to the realm of compound cross-section trapezoidal channels for both in-bank and overbank flows by using 20 flood events of the Tiber River in the Umbria region of Central Italy, and subsequently comparing the simulated results with the corresponding simulations of the HEC-RAS (Hydrologic Engineering Center – River Analysis System) hydrodynamic model and observed flow depth hydrographs. The field application, comparative study, and uncertainty and sensitivity analysis of the results demonstrate that the proposed multilinear discrete Nash-cascade stage-hydrograph (MDNS) routing model has the potential for routing floods in real-world rivers and canal irrigation systems, especially in operational mode.  相似文献   

Mineralogy, chemistry and genesis of Nishikhal manganese ores of South Orissa, India     

B. C. Acharya  D. S. Rao  R. K. Sahoo 《Mineralium Deposita》1997,32(1):79-93

Manganese ores of Nishikhal occur as distinctly conformable bands in the khondalite suite of rocks belonging to the Precambrian Eastern Ghats complex of south Orissa, India. Manganese minerals recorded are cryptomelane, romanechite, pyrolusite, with minor amounts of jacobsite, hausmannite, braunite, lithiophorite, birnessite and pyrophanite. Goethite, graphite, hematite and magnetite are the other opaque minerals and quartz, orthoclase, garnet, kaolinite, apatite, collophane, fibrolite, zircon, biotite and muscovite are the gangue minerals associated with these ores. The mineral chemistry of some of the phases, as well as the modes of association of phosphorous in these ores have been established. The occurrence of well-defined bands of manganese ore; co-folding of manganese ore bands and associated metasedimentary country rocks; the min-eral assemblage of spessartite-sillimanite-braunite-jacobsite-hausmannite; the geochemical association of Mn-Ba-Co-Ni-Zn together with the Si versus Al and Na versus Mg plots of the manganese ores suggest that the Nishikhal deposit is a metamorphosed Precambrian lacustrine deposit. Continental weathering appears to be the source for manganese and iron. After deposition and probable diagenesis, the manganese-rich sediments were metamorphosed along with conformable psammitic and pelitic sediments under granulite facies conditions, and subsequently underwent supergene enrichment to produce the present deposit. Received: 14 March 1995 / Accepted: 11 April 1996  相似文献   

Biostratigraphy and floristic evolution of coal swamp floras of a part of Talcher Basin,India: a window on a Permian temperate ecosystem     

Shreerup Goswami  Kamaljyoti Das  Mrutyunjaya Sahoo  Soumyaranjan Bal  Sanghamitra Pradhan  Kamal Jeet Singh  Anju Saxena 《Arabian Journal of Geosciences》2018,11(17):524

The present megafloral assemblage recorded from the Barakar sediments of Dholpahar section along Singda rivulet near Gopal Prasad Village in Talcher Basin comprises of equisetaceous stems, Gangamopteris buriadica, Palaeovittaria kurzii and 19 species of the genus Glossopteris. Record of Gangamopteris, Palaeovittaria and many narrow mesh forms of Glosspteris viz., G. angustifolia, G. churiensis, G. communis, G. recurva, G. spatulata, G. stenoneura, G. tenuifolia, G. vulgaris and G. zeilleri from two older fossiliferous horizons demonstrates that these fossils were preserved during Lower Barakar sedimentation. The report of middle and broad mesh forms of Glossopteris viz., G. barakarensis, G. browniana, G. indica, G. intermittens, G. karharbariensis, G. nakkarea, G. oldhamii, G. taeniensis and G. retifera in the youngest fossiliferous horizons reveals that these fossils were preserved during the deposition of Upper Barakar sediments. The continuation of some of the Karharbari plant fossils in the early phase of Barakar Formation and their disappearance in the flora of Late Barakar suggests a shift in the climatic setup. Palaeoclimate and palaeovegetation of this area are also summarised in this study. Moreover, the fossil assemblages of different fossiliferous beds of Dholpahar section demonstrate the evolution of midrib and meshes in different reticulate leaves.  相似文献   

Impact of LULC change on the runoff,base flow and evapotranspiration dynamics in eastern Indian river basins during 1985–2005 using variable infiltration capacity approach     

Pulakesh Das  Mukunda Dev Behera  Nitesh Patidar  Bhabagrahi Sahoo  Poonam Tripathi  Priti Ranjan Behera  S K Srivastava  Partha Sarathi Roy  Praveen Thakur  S P Agrawal  Y V N Krishnamurthy 《Journal of Earth System Science》2018,127(2):19

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   

Evaluation of NDWI and MNDWI for assessment of waterlogging by integrating digital elevation model and groundwater level   总被引：1，自引：0，他引：1  

Kanwar Vivek Singh  Shashikanta Sahoo  Avinash Prasad  Brijendra Pateriya 《国际地球制图》2015,30(6):650-661

Accurate information on the extent of waterlogging is required for flood prediction, monitoring, relief and preventive measures. The rule-based classification algorithms were used for differentiating waterlogged areas from other ground features using Resourcesat-2 AWiFS satellite imagery (Indian Remote Sensing Satellite with spatial resolution of 56 m). Two spectral indices normalized difference water index (NDWI) and modified normalized difference water index (MNDWI) were used for extracting waterlogged areas in Sri Muktsar Sahib district of Punjab, India. These indices extracted the waterlogged areas (cropped areas inundated with water) but the water features were less enhanced in the NDWI-derived image (when compared with MNDWI-derived image) due to negative values of NDWI and, mixing of water with built up features. The water features were more enhanced with MNDWI and the values of MNDWI were positive for water features mixed with vegetation. The overall accuracy of waterlogged areas extracted from the MNDWI image was 96.9% with the Kappa coefficient of 0.89. The digital elevation model (DEM) was extracted from ASTER-GDEM. The relationships among depth to the water table recorded before the incessant rain in the region, DEM and classified MNDWI images explained the differences in the extent of waterlogging in various directions of the study area. These results suggest that MNDWI can be used to better delineate water features mixed with vegetation compared to NDWI.  相似文献   

Grey analytic hierarchy process applied to effectiveness evaluation for groundwater potential zone delineation     

Satiprasad Sahoo  Amlanjyoti Kar  Prahlad Ram 《国际地球制图》2017,32(11):1188-1205

An attempt has been made to identify plausible groundwater potential zones (GWPZ) based on Grey Analytic Hierarchy Process Method (Grey-AHP) using integrated remote sensing and geographic information system. Grey-AHP combines the advantages of classical analytic hierarchy process and grey clustering method for accurate estimation of weight coefficients. The method also examines the effectiveness of GWPZ identification process. The proposed methodology has been applied to the Hirakud canal command area, Odisha (India). Feature layers [e.g. soil type, geology] are utilized for groundwater potential index (GWPI) calculation. The resulting GWPI map has been classified into three GWPZ namely: good, moderate and poor. Effectiveness based on grey clustering method is found to be in between ‘better’ and ‘common’ classes. Value of coefficient of determination (R² = 0.865) supports the obtained effectiveness evaluation result. This analysis demonstrates the potential applicability of the methodology for a general aquifer system.  相似文献   

Delineation of structural features over a part of the Bay of Bengal using total and balanced horizontal derivative techniques     

Satya Narayan  Soumyashree Debasis Sahoo  Ujjawal Kumar  Vipin Kumar Pathak  T. J. Majumdar 《国际地球制图》2017,32(4):351-366

The present study deals with classical problem of edge detection in potential field data over complex tectonic regime for both shallower and deeper sources, simultaneously. Balanced horizontal derivative (BHD) technique is a latest edge detection concept which delineates edges using balancing of amplitude responses for both shallower and deeper sources. The BHD technique has been validated by comparing with total horizontal derivative (THD) technique. Initially, three different synthetic models have been generated with spherical, cylindrical and vertical prismatic objects at different depths and corresponding gravity responses have been enhanced using BHD and THD techniques. Structural features have been delineated from EIGEN6C4 free-air gravity data using THD and BHD techniques over a part of the Bay of Bengal. Major lineaments have been identified in N–S direction followed by those identified along the NE–SW, NW–SE and E–W directions. Both studies of synthetic models and real gravity data reveal that BHD is an advanced technique than THD.  相似文献   

Petrology, 40Ar/39Ar age,Sr-Nd isotope systematics,and geodynamic significance of an ultrapotassic (lamproitic) dyke with affinities to kamafugite from the easternmost margin of the Bastar Craton,India     

N. V. Chalapathi Rao  Atiullah  R. Burgess  Purnendu Nanda  A. K. Choudhary  Samarendra Sahoo  B. Lehmann  Ngazipmi Chahong 《Mineralogy and Petrology》2016,110(2-3):269-293

  相似文献   

An Objective Analysis of Support Vector Machine Based Classification for Remote Sensing     

Thomas Oommen  Debasmita Misra  Navin K. C. Twarakavi  Anupma Prakash  Bhaskar Sahoo  Sukumar Bandopadhyay 《Mathematical Geosciences》2008,40(4):409-424

Accurate thematic classification is one of the most commonly desired outputs from remote sensing images. Recent research efforts to improve the reliability and accuracy of image classification have led to the introduction of the Support Vector Classification (SVC) scheme. SVC is a new generation of supervised learning method based on the principle of statistical learning theory, which is designed to decrease uncertainty in the model structure and the fitness of data. We have presented a comparative analysis of SVC with the Maximum Likelihood Classification (MLC) method, which is the most popular conventional supervised classification technique. SVC is an optimization technique in which the classification accuracy heavily relies on identifying the optimal parameters. Using a case study, we verify a method to obtain these optimal parameters such that SVC can be applied efficiently. We use multispectral and hyperspectral images to develop thematic classes of known lithologic units in order to compare the classification accuracy of both the methods. We have varied the training to testing data proportions to assess the relative robustness and the optimal training sample requirement of both the methods to achieve comparable levels of accuracy. The results of our study illustrated that SVC improved the classification accuracy, was robust and did not suffer from dimensionality issues such as the Hughes Effect.  相似文献