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1.
The development of groundwater favourability map is an effective tool for the sustainability management of groundwater resources in typical agricultural regions, such as southern Perak Province, Malaysia. Assessing the potentiality and pollution vulnerability of groundwater is a fundamental phase of favourability mapping. A geographic information system (GIS)-based Boolean operator of a spatial analyst module was applied to combine a groundwater potentiality map (GPM) model and a groundwater vulnerability to pollution index (GVPI) map, thereby establishing the favourable zones for drinking water exploration in the investigated area. The area GPM model was evaluated by applying a GIS-based Dempster–Shafer–evidential belief function model. In the evaluation, six geoelectrically determined groundwater potential conditioning factors (i.e. overburden resistivity, overburden thickness, aquifer resistivity, aquifer thickness, aquifer transmissivity and hydraulic conductivity) were synthesized by employing the probability-based algorithms of the model. The generated thematic maps of the seven hydrogeological parameters of the DRASTIC model were considered as pollution potential conditioning factors and were analysed with the developed ordered weighted average–DRASTIC index model algorithms to construct the GVPI map. Approximately 88.8 and 85.71% prediction accuracies for the Groundwater Potentiality and GVPI maps were established using the reacting operating characteristic curve method and water quality status–vulnerability zone relationship scheme, respectively. Finally, the area groundwater favourability map (GFM) model was produced by applying a GIS-based Boolean operator on the Groundwater Potentiality and GVPI maps. The GFM model reveals three distinct zones: ‘not suitable’, ‘less suitable’ and ‘very suitable’ zones. The area analysis of the GFM model indicates that more than 50% of the study area is covered by the ‘very suitable’ zones. Results produce a suitability map that can be used by local authorities for the exploitation and management of drinking water in the area. The study findings can also be applied as a tool to help increase public awareness of groundwater issues in developing countries.  相似文献   

2.
The study of the photolinears and the groundwater flow directions in the Lonavala area of the Pune distrtict suggests the relationship between these two parameters. In the western part of the Lonavala area the groundwater flow lines are running along a dark toned linear trending N 20° - 30°W. This linear is a fracture controlled linear valley covered by dense vegetation which is supported by the groundwater channelised along this linear. The higher specific capacities of the dugwells situated along the trend of this linear also suggest the movement of groundwater along the linear.  相似文献   

3.
It is a well established fact that geomorphology of an area exercises a significant control on the groundwater occurrence and movement. In an operational remote sensing project carried out by the National Remote Sensing Agency, India, this relationship between geomorphology and groundwater, coupled with the ability of Landsat data to provide regional geomorphic information, has been utilised to arrive at broad groundwater potential zones.  相似文献   

4.
Land use/land cover investigation have been carried out in Varaha river basia (VRB) using remote sensing data of 1986 and 1992 and the changes in land use/land cover during the period are estimated Visual interpretation techniques have been followed to delineate various land use/laad cover categories It is inferred that the land use/land cover pattern of the area is controlled by local topography, climate and resourees, The tesults revealed significant changes in the area of built-up land irrigated land, plantation degraded forest and upland over a period of six years.  相似文献   

5.
怀柔应急水源地是北京第一个建成的特大型应急备用水源地,经过数年的开采后,应急水源地水位大幅度下降,地下水漏斗面积不断扩大。PSInSAR技术在监测地面沉降方面具有很大的优势,本文利用PSInSAR技术和2003年—2009年间28幅Enviast卫星的ASAR影像监测怀柔应急水源地地区地面沉降情况,试验结果表明该地区平均沉降量为8mm/a。通过该地区地面沉降状况和地下水漏斗发展趋势之间的对比,发现地面沉降范围和地下水漏斗有较大的空间一致性,平面分布趋势整体上由南西—北东向北西—南东转变。  相似文献   

6.
The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) DEM and LANDSAT images of spatial resolution 30?m were used to construct groundwater potential zones (GPZ) map by integrating geological fractures, drainage network, slope and relief, and convergence index maps of the study area. Weight and score of each map were developed according to their level of contribution toward groundwater accumulation and spatial distribution of groundwater wells. The area that has very high potential for groundwater is located at the foot of Oman Mountains and Al Dhaid Depression covering an area of about 59.33?km², which is 4.40% of the study area. Further hydrological map and data on hydraulic properties of shallow aquifer, as recorded from observation wells in the regions, have been used to validate the produced GPZ map. The validation result showed sufficient agreement between the produced GPZ map.  相似文献   

7.
The study area around Saidnagar falls in Bundelkhand granitic terrain forming buried pediplain (granite derived material). The occurrence and movement of groundwater is restricted to the unconsolidated material, weathered and fractured rock. For the selection of tube-well sites, geoelectrical resistivity investigations have been carried out at the sites which are found suitable based on remote sensing and hydrogeological studies. Twenty six Vertical Electrical Soundings (VES) have been carried out by using Schlumberger electrode configuration, which have brought out 3 and 4 layered sub-surface sections. The resistivity of water-bearing weathered/fractured rocks varies from 10 to 20 ohm m, with thickness ranging from 3.4 to 75.0 m. The depth to the basement is found ranging between 6.8 and 93.0 m The integrated studies have revealed that the northern part of the study area forms groundwater prospective zone, consisting of unconsolidated water-bearing weathered material, In the southern part of the study area, weathered layer is either thin or absent and the groundwater movement and storage is restricted to the weathered/fractured zone only. This zone extends down to a depth of 3.4 to 75.0 m and may yield sufficient amount of water since it gets recharged by direct infiltration due to precipitation and percolation through Nalas.  相似文献   

8.
ABSTRACT

Groundwater potential mapping (GWPM) in the coastal zone is crucial for the planning and development of society and the environment. The current study is aimed to map the groundwater potential zones of Sindhudurg coastal stretch on the west coast of India, using three machine learning models: random forest (RF), boosted regression tree (BRT), and the ensemble of RF and support vector machine (SVM). In order to achieve the objective, 15 groundwater influencing factors including elevation, slope, aspect, slope length (LS), profile curvature, plan curvature, topographical wetness index (TWI), distance from streams, distance from lineaments, lithology, geomorphology, soil, land use, normalized difference vegetation index (NDVI), and rainfall were considered for inter-thematic correlations and overlaid with spring and well occurrences in a spatial database. A total of 165 spring and well locations were identified, which had been divided into two classes: training and validation, at the ratio of 70:30, respectively. The RF, BRT, and RF-SVM ensemble models have been applied to delineate the groundwater potential zones and categorized into five classes, namely very high, high, moderate, low, and very low. RF, BRT, and ensemble model results showed that 33.3%, 35.6%, and 36.8% of the research area had a very high groundwater potential zone. These models were validated with area under the receiver operating characteristics (AUROC) curve. The accuracy of RF (94%) and hybrid model (93.4%) was more efficient than BRT (89.8%) model. In order to further evaluate and validate, four different sites were subsequently chosen, and we obtained similar results, ensuring the validity of the applied models. Additionally, ground-penetrating radar (GPR) technique was applied to predict the groundwater table and validated by measured wells. The mean difference between measured and GPR predicted groundwater table was 14 cm, which reflected the importance of GPR to guide the location of new wells in the study region. The outcomes of the study will help the decision-makers, government agencies, and private sectors for sustainable planning of groundwater in the area. Overall, the present study provides a comprehensive high-precision machine learning and GPR-based groundwater potential mapping.  相似文献   

9.
The conservation areas in a plain are affected by the groundwater contamination from intense application of the fertilizers. The vulnerability of groundwater can be tested by using the DRASTIC model for the pollutants. The groundwater susceptibility to pollution in the various areas is mapped through DRASTIC model. However, the effects of pollution types and its characteristics are not considered, as this model is used without any modifications. This technique must be standardized for usage in the various aquifers and specific pollution types. The rates of DRASTIC parameters are corrected to obtain the potential for a more accurate analysis of the vulnerability pollution. The relationships between the parameters are identified with respect to the nitrate concentration in the groundwater by calculating the new rates. The methodology was applied to the selected area situated in the south eastern region of Iran at Kerman plain. Twenty-seven different locations were selected to test and analyse the nitrate concentration in the water from underground wells. The pollution in the aquifer was associated and correlated with the DRASTIC index by using the measured nitrate concentrations. The relationship between the index and the measured pollution in the Kerman plain was determined by applying the Wilcoxon rank-sum nonparametric statistical tests and the rates were calculated. It was found specifically in the agricultural areas that the modified DRASTIC model performed more efficiently than the traditional method for nonpoint source pollution, as indicated by the results. After modifications, the regression coefficients revealed that the relationship between the vulnerability index and the nitrate concentration was 77 %, while it was 37 % before the modifications were used. These statistics show that the modified DRASTIC performed far more efficiently than the original version.  相似文献   

10.
In the present paper, various groundwater potential zones for the assessment of groundwater availability in a hard rock terrain have been delineated with the help of hydrogeological parameters using satellite IRS- 1B-LISS-II digital data. Area selected for this study is a part of Bargarh district, Orissa, India covering an area of about 680 square km. Satellite data has been used to prepare geological-cum-lineaments, geomorphological, landuse and drainage maps. The various thematic maps have been integrated with the help of Geographic Information System to demarcate the poor to excellent groundwater potential zones. Weightage has been given to various groundwater controlling factors to the total groundwater potential in each segment of study area. Subsequently, several sites were selected and pumping tests carded out in the area. The results show that among others, lineaments as well as drainage density are the most important contributory factors in the groundwater potential of various geomorphic units in the area of investigation.  相似文献   

11.
Alaunja watershed, located on ‘Chotanagpur’ plateau of Bihar, is mainly under single cropping. The area receives more than 1000 mm of rainfall but it has not been utilised properly to increase the agricultural output. The remote sensing, geophysical, DBTM (Digital Basement Terrain Model) and GIS (Geographic information System) techniques were used for providing scientific database for sustainable utilisation of water resources in watershed perspective. The landuse, soil and surface water body maps have been prepared using remotely sensed data. DBTM has been generated based on depth of basement information derived from geophysical data to provide information regarding aquifer geometry, fracture zones and sub-surface basins. Analysis indicated that surface and groundwater resources have potential to irrigate 53 per cent of geographical area of the watershed. But at present, this available potential has been utilised only to irrigate 7.03 per cent area of the watershed. Feasibility for large scale development of groundwater through dugwell is possible only in 2 per cent area of the watershed. The available groundwater potential to irrigate 28 per cent area of watershed can not be utilised through dugwells. The surface water potential is also poorly utilised. The present study also helped in prioritising the water resource development activities.  相似文献   

12.
Water harvesting works had been conducted at Jamka micro-watershed of Saurashtra region of Gujarat in India for augmenting artificial groundwater recharge in hard rock aquifers of the semi arid region. In present study groundwater recharge of Jamka micro-watershed was estimated. The natural groundwater recharge through rainfall in the study area was estimated using empirical equations and the artificial groundwater recharge through water harvesting structures which was estimated using remote sensing and GIS. The area under submergence due to water harvesting structures is estimated using remote sensing images. The groundwater recharge in study area was also estimated using water table fluctuation method and compared with total recharge through rainfall and water harvesting structures. The natural groundwater recharge through rainfall in the study area was found varying from 11 to 16 per cent of annual rainfall. The total groundwater recharge in the study area was estimated 390.29?ha?m, in which the contribution of recharge through water harvesting structures was about 38.53%; this revealed that the water harvesting structures played an important role in increasing the groundwater recharge in the region.  相似文献   

13.
The study area around Choral river basin in the Narmada valley region, forms a part of Indore and Khargone districts of Madhya Pradesh. The geological, geomorphologic, lineament, hydrogeomorphic and groundwater potential zone maps of the study area have been prepared using IRS IC LISS III FCC imagery on 1:50,000 scale. Various litho-units, different land-forms, lineament fabric and hydro-geomorphic units have been worked out by visual interpretation methods and frequent field checks. The integrated hydro-geomorphological map of the study area reveals that the groundwater potential in denudation landforms such as buried pediplains, plateaus, denudational and residual hills is moderate-to-poor. On the other hand, the groundwater occurrence in structural landforms like structural hills, lineaments/faults and narrow gorges is likely to be good to moderate and the depositional landforms namely alluvial plains, valley-fills and meandering-channels favour the accumulation of sub-surface water and, therefore, may be considered as good recharge zones. From the point of view of groundwater occurrence, various hydro-geomorphic units have been classified as high, moderate and low potential zones.  相似文献   

14.
The main objective of the present work is to delineate the groundwater potential zones in Bilari watershed of district Shivpuri, Madhya Pradesh. Remote Sensing data and GIS were used to delineate the groundwater potential zones of the area. IRS-1D (LISS III) data have been utilized to extract information on various themes such as geomorphology, structure, drainage and land use/land cover. Available lithology and soil maps have also been used. DEM has been generated from contours taken from Survey of India topographical maps in order to obtain the slope percentage and slope aspect of the area. The groundwater potential zones were delineated by weighted overlay analysis. The themes geology, geomorphology, slope and soil were considered and the weightages assigned to different classes of respective themes according to their role in groundwater potential. Finally, five groundwater potential zones viz., very good, good, moderate; poor and very poor were delineated for the study area. It was estimated that about 110.41?sq km area which forms 37.55% of the total area are in the zones of very poor, poor and moderate category and about 183.75?sq km (62.45%) in zones of good and very good category.  相似文献   

15.
Groundwater exploration in the Western Doon valley has been carried out to delineate the groundwater potential and groundwater quality zones suitable for domestic purposes based on the integrated use of Remote Sensing and Geographical Information Systems (GIS). The Western Doon Valley, occupying broad synclinal troughs in the evolving fold-thrust system of sub-Himalaya, which is filled by post-Siwalik fluvial and debris flow deposits in the late Quaternary-Holocene. The Western Doon Valley area is bounded by the Mussoorie range in the north with 1800–2800 m elevation and in the south by young topographic relief of the frontal Siwalik range with ~800 m average elevation. Groundwater quality of Western Doon valley through pictorially representation in the GIS environment, it is inferred that calcium, magnesium, total hardness and nitrate at some locations above the desirable limit. The groundwater prospects map has been prepared by integrating the hydrogeomorphologic, land use/land cover from satellite data (IRS-ID, LISS-III data) slope, soil, drainage density, depth to water table of pre-monsoon and post-monsoon periods (unconfined aquifer), water table fluctuation, static water level (confined to semi-confined aquifers), specific capacity, discharge and drawdown maps using index overlay method in the GIS environment. The groundwater prospects are depicted in five categories Very high, high, moderate, low and very low (runoff zone) integrated with the groundwater quality zones which have been prepared from hydrochemical data. The results indicated that 16.82 % of the area is under Very high potential zone category with 16.11 % and 0.71 % of desirable and undesirable quality of groundwater and 18.65 %, 42.06 %, 6.96 % and 15.46 % classified as high, moderate, low and very low potential zones with desirable and undesirable quality of groundwater for domestic purposes. This study be useful for designing the groundwater prospects and management plan for the sustainable development of study area.  相似文献   

16.
A methodology for groundwater evaluation has been developed by the combined use of numerical model and spatial modeling using GIS. The developed methodology has been applied on the sub-basin of the Banganga River, India. Initially, the groundwater potential zones have been delineated by spatial modeling. Different thematic maps of the basin like geology, geomorphology, soil, drainage, slope factor and landuse/landcover have been used to identify the groundwater potential zones. Further, the groundwater flow model for the study area has been developed in the MODFLOW. The groundwater flow vector map has been developed and superimposed on the potential zone map to validate the results of spatial modeling. Finally, the different scenarios have been conceptualized by varying the discharge of the wells and purposing the location for new rainwater harvesting structures. Results reveal that increasing the discharge of the wells in the potential zones put less stress on the aquifer. The suggested locations of rainwater harvesting structures also help to reduce the overall decline of groundwater in the area. The hydrological and spatial modeling presented in this study is highly useful for the evaluation of groundwater resources and for deciding the location of rainwater harvesting structures in semi-arid regions.  相似文献   

17.
The present study was aimed to identify and delineate the groundwater potential areas in parts of Western Ghats, Kottayam, covering the upper catchment of Meenachil river. The study area is composed rocks of Archaean age and Charnockite dominated over others. The information on lithology, geomorphology, lineaments, slope and land use/land cover was generated using the Resourcesat (IRS P6 LISS III) data and Survey of India (Sol) toposheets of scale 1:50,000 (surveyed in 1969) and integrated them with raster based Geographical Information System (GIS) to identify the groundwater potential of the study area. Thus, a GIS-based model which takes account of local condition/variations has been developed specifically for mapping groundwater potential. On the basis of hydrogeomorphology, three categories of groundwater potential zones namely good, moderate and poor were identified, and delineated. The high potential zones correspond to the fracture valleys, valley fills, pediments and denudational slope, which coincide with the low slope and high lineaments density areas. The low zone mainly comprise structural hills and escarpments and these act as run-off zones. The derived panchayath-wise groundwater potentiality information could be used for effective identification of suitable locations for extraction of potable water for rural populations.  相似文献   

18.
The relevance of satellite remote sensing in groundwater exploration stems from the utility of satellite images in identifying and delineating various featares that may serve as direct or indirect indicators of the presence of groundwater. This paper presents the results of hydrogeomorphological mapping using IRS-IB LISS II data and evaluation of groundwater prospects of each. hydrageomorphologic unit on the basis of lithotogy, struclure, landfrom and available aquifer data in the Shahbad tehsil, Baran district, Eastern Rajasthan, The study has shown that in the western parts of the area the Vindhyan sandstones (Lower Bhander) in which groundwater occurs under unconfined to confined conditions along bedding planes and fracture zones have vast potential for groundwater development thtough deep bore-wells or dng-cum-barewells, while in the eastern parts where shales dominale, large diameter dug wells are suitable to tap the limited groundwater resources. Infiltration (or recharge) tube wells have been proposed to augment the sandstone aquifers.  相似文献   

19.
Godavari sub-watershed is a part of buried pediplain developed over ‘Chotanagpur’ granite gneiss. Aquifer is unconfined in nature and groundwater occurs under water table condition. In the study area, groundwater is being exploited only through dugwells which are not capable of sustaining long duration pumping. Groundwater exploration involves the investigation of depth and nature of weathered and fractured horizon. To understand the groundwater storage and retrieval in the area, the basement topography derived from Digital Basement Topography Modelling (DBTM), the lineaments identified on remotely sensed data and geohydrological and physiographic data have been analysed. From DBTM, fracture zones have also been inferred. Lineaments (probable fractures) identified with the help of remotely sensed data are linear features representated on a planner surface. Lineaments in the area are subtle in expression due to deeply buried pediplian. Correlation of lineaments with DBTM reveals that a few lineaments/fractures are deep seated and a few have no sub-surface extensions. Also some sub-surface fractures inferred from DBTM have no expressions on the image. Attempt has been made to delineate more authentic lineaments/fractures with the help of remotely sensed data and DBTM. Correlation of probable fractures inferred from remotely sensed data and fracture zones inferred from DBTM indicated that 40 per cent of lineaments seems to be real fractures. Higher correlation may be achieved where lineaments are prominent and reproducible. It has also been observed that those lineaments which correlate with the fracture zones inferred from DBTM, are also not completely traceable in their linear extent. The exaggeration in length of lineaments may be due to subtle nature of lineaments. Correlation shows that remotely sensed lineaments are improtant for groundwater exploration and its authenticity can be further ascertained with DBTM.  相似文献   

20.
Abstract

In the present study, the multi-temporal satellite images of IRS P6 LISS III were used to map waterlogging dynamics over different seasons. An area of 594.36 km2 (6.75%) and 4.17 km2 (0.04%) was affected by surface waterlogging during pre and postmonsoon season, respectively. The average annual groundwater level fluctuations were calculated using 18 years (1990–2007) pre and postmonsoon groundwater level data to identify the areas which are under groundwater induced waterlogging conditions. The soil map clearly indicates that salinity and sodicity exhibit the highest severity and occur in areas with shallow groundwater levels. The hydrogeomorphical units mapped using IRS P6 LISS III satellite images are flood plain, alluvial plain, paleochannels, and oxbow lakes. The study revealed that 44.65% areas have very good to excellent groundwater resources. The litholog data clearly indicate an alternating sequence of clay and sand in which deep aquifers made up of coarse sand would be best suited for adequate water supply and good groundwater quality. The integrated study utilizing digital spatial data pertaining to waterlogging, soil salinity, water level fluctuation, and lithological variation proved that planning of any surface and subsurface water resources development activity should be taken up after assessments of said parameters.  相似文献   

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