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Pathak S.,Regional Remote Sensing Center West | Bhadra B.K.,Regional Remote Sensing Center West | Sharma J.R.,Regional Remote Sensing Center West
International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences - ISPRS Archives | Year: 2012

The area lies in arid zone of western Rajasthan having very scanty rains and very low ground water reserves. Some of the other problems that are faced by the area are disposal of industrial effluent posing threat to its sustainability of water resource. Textiles, dyeing and printing industries, various mechanical process and chemical/synthetic dyes are used and considerable wastewater discharged from these textile units contains about high amount of the dyes into the adjoining drainages. This has caused degradation of water quality in this water scarce semi-arid region of the country. Pali city is located South-West, 70 Kms from Jodhpur in western Rajasthan (India). There are four Common Effluent Treatment Plant (CETP) treating wastewater to meet the pollutant level permissible to river discharge, a huge amount of effluent water of these factories directly meets the into the river Bandi - a tributary of river Luni. In order to monitor the impact of industrial effluents on the environment, identifying the extent of the degradation and evolving possible means of minimizing the impacts studies on quality of effluents, polluted river water and water of adjoining wells, the contamination migration of the pollutants from the river to ground water were studied. Remote sensing analysis has been carried out using Resourcesat -1 multispectral satellite data along with DEM derived from IRS P5 stereo pair. GIS database generated of various thematic layers viz. base layer - inventorying all waterbodies in the vicinity, transport network and village layer, drainage, geomorphology, structure, land use. Analysis of spatial distribution of the features and change detection in land use/cover carried out. GIS maps have been used to help factor in spatial location of source and hydro-geomorphological settings. DEM & elevation contour helped in delineation of watershed and identifying flow modelling boundaries. Litholog data analysis carried out for aquifer boundaries using specialized software. Establishment of other boundary conditions was based on well data. Calibration and validation of was done using ground water modelling software. Change detection analysis indicated areas of impact on land use/cover particularly, agriculture activity. Normalised difference vegetation index found to have negative correlation with pollution level. Population dynamics have been studied and it is found to be poorly correlated with land degradation. Water levels do not show significant variations in past twenty years baring normal seasonal fluctuation. Chemical analysis of ground water samples studies in time series. The water quality studied through various parameters shows concentration in mid-reach of the Bandi river. Analysis of litholog data shows three unconfined aquifers. Pump test and resistivity survey was carried out for initial aquifer properties in local water levels. Modelling contaminant migration helped in prediction of the extent of the adversity. Surface flow is checked allowing more water but it is proving to be accumulation point in absence of good rainfall & flow in the river. Hotspots of dumping/active contamination were identified with certain remediation efforts and supply of solid waste to cement industry in addition to bio-filter for heavy metals. © 2012 ISPRS. Source

Bhadra B.K.,Regional Remote Sensing Center West | Pathak S.,Regional Remote Sensing Center West | Karunakar G.,ZINC Inc | Sharma J.R.,Regional Remote Sensing Center West
Journal of the Indian Society of Remote Sensing | Year: 2013

Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) SWIR bands are used in identification of alteration zones which have developed during hydrothermal activity. Among the available methods of hyperspectral data analysis, PCA and RBD techniques are found to be useful in delineation of clay alteration and iron oxide zones. ASTER data analysis by PCA and RBD of (B5+B7)/B6 shows delineation of two distinct alteration zones with characteristic mineral assemblages viz. propylitic zone (chlorite, epidote, montmorillonite and calcite) and phyllic zone (illite, kaolinite, white mica and quartz). Iron oxide rich zones (gossans) have been delineated using ASTER band ratio technique (B2/B1). Geochemical dispersion of soil samples shows that Pb and Zn concentration is higher in phyllic and propylitic zones around Sawar and Malpura area respectively. Thus, ASTER data shows the potential in discrimination of metasedimentary rocks and delineation of alteration zones for targeting base metals around Sawar-Malpura area in central Rajasthan. © 2012 Indian Society of Remote Sensing. Source

Bhadra B.K.,Regional Remote Sensing Center West | Pathak S.,Regional Remote Sensing Center West | Sharma J.R.,Regional Remote Sensing Center West
Journal of the Geological Society of India | Year: 2013

Groundwater pollution due to industrial effluents from textile units around Pali city area is the major concern to the local villagers and the district administration. Indiscriminate discharge of these effluents in the past two decades caused severe damage to the agricultural land and groundwater resources within 3 km buffer zone of the Bandi river. Remote Sensing and GIS techniques are found to be better tools in assessing the damage in agricultural crops during 1997 and 2006 with the help of high resolution satellite images. Groundwater fluctuation trend with annual rainfall pattern during 1985 and 2005 indicate good recharge in the study area. Detailed analysis of groundwater quality parameters (TDS, Cl and SO4) and heavy metals (Cu, Pb, Zn, Fe, Cd and Cr) for 1997-98 indicates maximum concentration around Chatelao village and Dholera Jagir in the downstream direction of Bandi river. However, temporal analysis of groundwater samples collected in January, 2009 shows marginal decrease in concentration of TDS, Cl, SO4, Pb and Cu in both groundwater as well as river effluents. Slight improvement in water quality especially heavy metals in the last 12 years (1998-2009) may be attributed to the appropriate measures (treatment of wastewater and solid waste disposal) taken by the establishment of three Common Effluent Treatment Plants (CETP) in Pali city area. However, a few stringent actions may be taken to avoid direct discharge of the effluents into Bandi river. © 2013 Geological Society of India. Source

Joseph M.,Regional Remote Sensing Center West | Subramoniam S.R.,Regional Remote Sensing Center West | Srinivasan K.S.,Regional Remote Sensing Center West | Pathak S.,Regional Remote Sensing Center West | Sharma J.R.,Regional Remote Sensing Center West
Journal of the Indian Society of Remote Sensing | Year: 2013

The potential of quad polarization radar data for the target discrimination has been analyzed. Quad polarization data of the RADARSAT-2 fine resolution mode has been utilized. Class separability analysis has been carried out on different polarization combinations using Transformed Divergence (TD) method and it is observed that HH-HV/VH-VV polarization combination gives better class separability when compared to other polarization combinations. Classification has been carried out on the optimized polarization combination using Maximum likelihood (MLC) and Support Vector Machine (SVM) classifiers. It is observed that SVM classification gives better classification accuracy compared to MLC. Overall classification accuracy is 93. 03% for SVM and 88. 78% for MLC. Class separability and classification accuracy comparison results are presented. © 2012 Indian Society of Remote Sensing. Source

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