SOI Toposheets Research Articles

Exploring and modelling the hydro-morphological landscape of a Himalayan basin: a geospatial study of Nandakini Basin in Uttarakhand, India

This study comprehensively examines the hydro-morphological, topo-hydrological, and physiographic features of the Nandakini catchment in the north-western Himalayas. In the absence of extensive hydrological data, employing morphometric parameters proves to be a crucial and efficient approach for delineating geological structures and assessing hydrodynamic activity in the river basin. Utilizing SRTM DEM, SOI toposheets, and GIS, the study identified twenty watersheds within the catchment, estimating its total area at 540.98 km2. The analysis revealed a 6th-order catchment with a primarily sub-dendritic to dendritic drainage pattern, susceptible to flooding and gully erosion from slow surface runoff. The elongated shape and compactness coefficient indicated delayed peak runoff. Coarse drainage texture and high relief ratio suggested increased vulnerability to erosion. Physiographic indices indicated a later youth stage of basin development, while topo-hydrological indices highlighted significant topographic and spatial variability in water availability, emphasizing erosion potential. This study provides valuable insights for developing sustainable catchment management plans and informing decision-making in water resources management for the Nandakini catchment.

Quantitative Assessment of Channel Migration in the Ghaghara River, Ganga Plain, India

ABSTRACT The Ghaghara River is one of the longest tributary of the Ganga River. The Ghaghara, a snow fed river is well known for channel shifting/migration. It was analyzed for lateral migration using multi-temporal satellite images and SOI toposheets. It shows 4.2 to 6.1 km lateral migration in last 45 years (1975–2020) between Bahraich and Deoria in the state of Uttar Pradesh. The lateral migration on the left side of the river (NNE) is 6144, 4838, 6475 and 4755 m, whereas on the right side (SSW) is 7021, 4555, 4718 and 4257 m during 1975–1990, 1975–2000, 1975–2010 and 1975–2020, respectively. The rate of migration (m/year) on left side (NNE) is 410, 194, 185 and 106, whereas on the right side (SSW) is 468, 182, 135 and 95 during 1975–1990, 1975–2000, 1975–2010 and 1975–2020, respectively. The major factors such as heavy precipitation, reactivation of chute channels, deposition of sediments, breaching of embankments and sand mining etc. might be responsible for the lateral migration of the river. Human settlements should be constructed away from the migration-prone area and regular monitoring and management system needs to be in place to mitigate the impacts of such natural events.

Takhar Province Morphometric Analysis for the Watershed Management of Amu River Basin in Afghanistan by using Remote Sensing & GIS

The drainage characteristics are basic information for watershed management. The morphometric analysis carried the slope contribution and linear, areal, and relief aspects. Takhar province is 390 km distance from Kabul. Located in the North Eastern Region of the country, the capital of Takhar province is Taluqan (Provincial Center). Badakhshan borders Takhar in the North-East, Panjsher in the south, Baghlan in the South-West and Kunduz in the North-West. Takhar is situated at an elevation of 801 meters above sea level and covers a land area of 12328.684 Km2, representing 1.91 percent of the total Afghan territory. The SRTM (90 m) Digital Elevation Model (DEM), in conjunction with SOI toposheets, have been used to delineate the hydrological boundaries of the study area. The finding variation in the elongated shapes of the basins is due to the guiding effect of faulting and thrusting in the basin. The Rc of the basins is fewer than 1. It indicates that the infiltration rate varies throughout the basin. The Bangi, Farkhar, and Warsaj districts have low Fs, which indicates that there is less side flow for a shorter duration and high main flow for a longer duration. High Fs in Khwaja ghar, Taluqan, and Darqad districts with high side flow for a longer duration and low main flow for a shorter duration causing high peak flows in a shorter duration.

Morphometric Analysis for Sustainable Development of Watersheds Using Multisensor Satellite Data: A Case Study from Shiriya River Basin

Objectives: The goal of this research is to calculate, compare and analyze the morphometric drainage parameters of Shiriya River Basin (SRB), Kasaragod, Kerala, using DEMs acquired by different satellite sensors and topographic data (SOI toposheet) for sustainable watershed development. Methods: The Arc GIS 10.3.1 software was used to measure linear, relief, and areal aspects of morphometry. The input data used for deriving the drainage network of the SRB were SOI toposheet (1:50000 scale), SRTM DEM (90m), Cartosat, ASTER and ALOS PALSAR DEM of resolution 30 m each. The relative error percentage of basic parameters derived from DEMs concerning the toposheet is calculated. A groundwater potential map is prepared using weighted overlay analysis of thematic layers (geology, geomorphology, slope, drainage density, lineament density and depth to water level). Findings: Present study revealed that the parameters derived from SRTM DEM data are more similar to those derived from toposheet. Most of the parameters obtained from each input DEM are more or less equal, and the minor variation may be due to varied data collecting and processing methodologies used for DEM creation. SRB is characterized by 6 th order stream with a dendritic drainage pattern, which is elongated and less susceptible to soil erosion. SRB has an intermediate texture and is in a mature stage of geomorphic evolution. Inference from the ground water potential zonation map indicates that major portion of the SRB has moderate ground water potential. Application/improvement: The study would be a valuable source for identifying water recharge sites, basin modelling, and groundwater prospect mapping. Novelty:This research has attempted to compare and analyze the morphometric parameters’ results from multisensor satellite data for sustainable watershed management. An attempt has been done to understand the relation between morphometric parameters and ground water potential of SRB using Groundwater potential zonation map. Keywords: Drainage morphometry; Shiriya River basin; GIS; Karnataka; Kerala

Spatial assessment of groundwater quality using CCME-WQI and hydrochemical indices: a case study from Talupula Mandal, Ananthapuramu district, South India

Fluoride contamination in groundwater is known from different villages of Talupula Mandal. In the present study in part of SoI toposheet no.57 J/8) of Ananthapuramu district, Andhra Pradesh, the magnitude and credible geogenic sources of the fluoride contamination in groundwater are studied. The present study carried out includes 30 groundwater samples covering an area of 442.89 sq km using (GIS) and (CCME-WQI) techniques. Problem is causally related to fluoride intoxication of human beings and animals through drinking waters. Well waters in the Talupula Mandal surrounded areas carry a high level of fluoride concentrations, much above the internationally decided safety limits. ‘Fluorosis’ is imminent as a result of prolonged intake of waters with more than 1 to 1.5 ppm of fluoride. Fluoride testing results of groundwater from borewell pump using fluoride test kit reveal that about 50% groundwater samples show fluoride concentration more than 4.0 mg/l, 30% samples show between 2.0 and 3.0 mg/l and 20% samples show fluoride concentration is 1–2 mg/l and above (BIS permissible limit: 1.5 mg/l). Agriculture indices are as follows: sodium percentage (Na%) was found between ranges (20.04–55.26), sodium absorption ratio varies from 0.86 to 3.91), Kelly's ratio (KR) varies from 0.22 to 1.16, residual sodium carbonate varies from − 4.12 to 20.66), permeability index (PI) varies from 39.00 to 82.28, magnesium hazard varies from 52.83 to 85.47, potential salinity varies from (0.71–3.15); results shown that the majority of the groundwater samples were suitable for irrigation uses. According to Gibbs’ ratio samples Gibbs ratio 1 (0.04–0.45) and Gibbs ratio 2 (0.44–0.81) fall in the rock dominance. Major ion compositions plotted on a Piper tri-linear diagram indicate that the water is of Ca-HCO3 type and is mixed Ca–Mg–Cl type. The present study indicates that the groundwater chemistry is mostly controlled by geogenic processes (weathering, dissolution and ion exchange) and some extent of anthropogenic activities.

Prioritization of Sub-Watersheds in Ruparel Watershed, Rajasthan Based on Morphometric and Land Use/Land Cover Analysis Using Remote Sensing and GIS

Watershed prioritization is considered as the most significant aspect in watershed resource management and development program. The present work attempts to prioritize seventeen sub-watersheds in Ruparel watershed of Alwar district of Rajasthan, India. For prioritization of sub-watersheds, morphometric and land use/land cover (LULC) analysis were performed using remote sensing and GIS. Base map of the study area has been derived from SOI toposheet on 1:50,000 scale whereas LULC mapping was done using IRS P6 LISS III data. Standard methods for drainage morphometry have been followed for computing morphometric parameters such as linear and shape for seventeen sub-watersheds and allotted ranks based on their relationship with erodibility and a compound value has been calculated for final ranking. Five main LULC categories were computed and were assigned priority ranks and subsequently a compound parameter was determined for final ranking. Integration of both morphometric and LULC results reveal that SBW5, SBW7, SBW12 and SBW16 are the common sub-watersheds that fall under high priority, SBW3 falls under Medium category and SBW11 comes under low priority. The results of the analysis can be used to identify the sub-watersheds which need immediate restoration and will eventually help in watershed resource management for sustainable development.

Land-use change mapping and analysis using remote sensing and GIS for watershed evaluation- A case study

Watershed development and its management are dynamic with new challenges and complexities, rendering difficulties in laying out a proper development plan. There is a need for an accurate process to assess the progress of implementation. Its assessment and evaluation need a holistic approach through reliable methods. Increasing the number of indigenous remote sensing satellites, reasonable pricing of indigenous satellite data and trained human resources have further facilitated the application of remote sensing for watershed management. In this study, a cluster of five watersheds, three in Telangana State (Mangalagudem, Rampur, Chilkepalli) and two in Andhra Pradesh (R.N. Palle, Nathiobanagari Palle-II) were taken up for watershed evaluation study. A detailed methodology for the impact evaluation of watersheds using remote sensing and geographical information system (GIS) is presented in this paper. Post classification comparison of pre-and post-implementation satellite imagery for watershed is being used for impact evaluation. Land use classification was done using SOI toposheet of 1:25,000 scale and LISS- IV (MS) remote sensing imagery. Results clearly show that interventions to check soil erosion and water run-off in a watershed mode increased Rabi cropped area up to 61 per cent and Kharif cropped area up to 22 per cent in all the watersheds. There was about a 47 per cent decrease in the extended fallow area in Nathiobanagari Palle-II watershed. Thus, interventions for checking soil erosion and runoff lead to the area's sustainable development in all the evaluated watersheds.

Cadastral level Soil and Water conservation Priority Zonation using Geospatial technology

Water is the most precious commodity that human being wanted, nowadays water is depleting due to several human interventions. In Kerala state, even though high rainfall is received, still water scarcity is faced during summer and soil erosion is higher. This watershed area is prone to water scarcity during the summer season and stream network become dry during that period. This clearly indicates that human interventions and unscientific agricultural activities may be the result. In this, study GIS and RS technologies are used to find and map the Soil and water conservation priority zones, also several action Plans where proposed. SOI Topo sheet were used to digitize the contours and DEM was created using that with ArcGIS 10.2.2 software. LULC maps were digitized from satellite image and using other parameters and suitable weight values, the weighted overlay was done to find out the Priority Zones. Cadastral Plot boundaries were overlaid for plot-wise priority zones and several conservation methods like gully plugin, check dams, vegetation bund etc. were proposed.

A Study of Vegetation Geomorphology Relationship along the sections of Balasore and Kanthi Coastal Plains, India

Coastal geomorphology deals with the various landforms and different processes involved in the development of coast. In the alluvium coast, biology plays a significant role as a coastal process. The present study aims at the role of vegetation in the geomorphic system, with the main consideration of flora. The study has been conducted in an alluvium coast along the Bay of Bengal adjacent to the sections of Balasore and Kanthi coastal plain. The geomorphological map and Normalized Difference Vegetation Index (NDVI) have been generated with the help of Landsat 5 TM, Landsat 8 OLI & SOI Toposheet with the help of Arc GIS & Erdas Imagine software. The ground truthing of relationships between geomorphological units & vegetation types are established with the help of GPS survey and counting of species type. The selected nine environmental transects of Balasore and Kanthi coastal plains i.e. Dagara, Kankadapal, Talsari, Udaipur, Digha, Shankarpur, Tajpur, Mandarmani & Junput have been considered for assessing the role of vegetation in sediment accretion and sediment surface stability. The study shows that the surface stability is achieved with dense vegetation covers and their types in Mangrove Swamp, Salt marsh and sand dunes whereas; the erosional area of geomorphic units has less vegetation cover and insignificant species type. The perfect relationship are found in the shore transect of Balasore-Kanthi coastal interface area (New Digha to Bichitrapur). Finally, it is also observed that the above area is less disturbed by human activities in compare to others.

Spatio-Temporal Dynamics of Landuse/Land Cover Around NTPC Using High Resolution Satellite Imagery

Land is becoming scarce resource due to population growth and industrialization. Rapid growth of human activities can also be attributed as one of the reasons. Thus, it becomes an important task to regulate land resource for sustainable development and environmental protection. LULC change studies have become a central component in current strategies for managing and planning land resources and monitoring environmental changes. In this paper an attempt has been made to bring out spatio-temporal dynamics of LULC patterns of NTPCRamagundam and its surrounding environment by using multi-temporal satellite data of Landsat-4, IRS P6 LISS-III and IRS 2 LISS-IV and GIS techniques for the years 1984, 2005, 2011, 2015, 2018. The methodology includes base map preparation having features like Road (SH), Rail, Canal, River, Stream, Tanks, Forest boundary and other administrative boundaries from SOI topo sheet and the features digitized are updated on satellite images. Interpretation of study area for LULC feature extraction on satellite imageries of respective years is carried with Nrsc’s standard LULC classification system. Change detection statistics can be generated out of 5 LULC thematic layers obtained and analysed specially with respect to NTPC environs. Results from this study shows the percentage of geographical area occupied by built-up land, agricultural land, forests, wasteland and waterbodies of level-I LULC features were 10.27%, 60.68%, 6.61%, 11.81%, 10.63% respectively in 1984 and were changed into 21.41%, 48.51%, 5.97%, 12.77%, 11.34% respectively in 2018. This analysis shows a rapid growth in built-up land and fall in agricultural land between 1984 and 2018. There is a considerable change in the remaining features from 1984 and 2018.

Glacier mass loss in the Alaknanda basin, Garhwal Himalaya on a decadal scale

The Himalayan glaciers significantly contribute to the largest river systems like the Indus, Ganga, and the Brahmaputra. The change in glacial area and mass can affect the mountain community and people living in the Indo-Gangetic plain. The present study adopted the geodetic method to estimate the elevation change and mass budget of 61 glaciers in the Alaknanda Basin, using the satellite data of Cartosat-1 (2011, 2014, 2017) and SRTM (2000). Besides, the DEM of 1962 (SOI Toposheet) and 2000 (SRTM) is used to estimate the mass budget of Satopanth (SPG) and Bhagirath Kharak glaciers (BKG). The field debris thickness of SPG (2015-2017) is compared with the elevation change (2000-2017). Further, we have compared the mass loss of the glaciers with their volume. The results suggest the sustained mass loss of 1.85 ± 0.10 Gt out of 33.9 ± 8.8 Gt for 61 glaciers in the basin from 2000-2017. The mass loss of SPG and BKG during 2000-2017 is 0.20 ± 0.02 Gt and 0.24 ± 0.03 Gt, whereas from 1962 to 2000, is 0.083 ± 0.03 Gt and 0.091 ± 0.04 Gt, respectively. The analysis facilitates a better understanding of glacier mass changes in the Alaknanda basin on a multi-decadal scale.

Geographical vulnerability to respiratory infections using GIS technique- micro analysis study in the Himalayan region-India

The study appraised the role of geo physical and socio-economic factors in the causation of respiratory infections in Geographic Information System (GIS). Altitude zonation along with superimposition of human settlements was extracted using Digital Elevation Mode of 30 m resolution and SOI toposheets 1971 in Arc GIS software 10.2. Aerosol Optical Depth (AOD) was generated through Moderate resolution imaging spectroradiometer. Wind Chill Factor the cooling sensation caused by the combination of air temperature °C and wind speed was also calculated using recommended formula of National Weather Services United States of America (US). Geographical vulnerability index were gauged by calculating incidence rate per thousand of population, relative risk rate, odds ratio, normal standard score (Z value) of respiratory cases obtained through medical records and field survey carried under the medical supervision. Kendal ranking method and composite index techniques were used to estimate the intensity of respiratory diseases, medical block analysis to identify hotspot areas by generating disease index map in GIS using SOI toposheets 1971. With non availability of data related to socio-economic and behavioral attitudes, the desired information were carried through semi structured questionnaire. With longitudinal depression valley characterized with high ecological sensitive zone makes the habitants more vulnerable to respiratory infections through exposure to evaded chilly winter months, exposure to pollutants, poor socio-economic and behavioral environment increases the degree of vulnerability. Identifying the hotspot areas in GIS environment will be useful in formulating and executing plans at the ground level more effectively and efficiently.

Determination of sensitivity of drainage morphometry towards hydrological response interactions for various datasets

A network of drainage patterns and associated morphometric analysis are important as it forms various attributes of a watershed. Analysis of these attributes is carried out by spatial analysis which is essential for studying several hydrological response interactions within the watershed catchment area. In the present work, five stream networks of a head watershed Verakhadi were derived from SOI toposheet (scale = 1:50,000), SRTM-GL1, AW3D30, GDEM-V2 and CartoDEM-V3.1. The calculated basin morphometric attributes of drainage network derived from all four 30-m-resolution satellite-based DEMs were compared with SOI toposheet-based drainage network which is essential for estimating the accuracy of watershed hydrological response to a natural event (storm). The capability of all four satellite-based DEMs to represent linear, areal and relief aspect of the drainage basin was evaluated. Morphometric parameter comparison of stream network derived from various DEMs is an indirect way of assessing the relative vertical accuracy of DEM. It is observed that DEMs with same spatial resolution can have variable morphometry derivatives due to different data acquisition and data processing techniques used for DEM generation. The outcome of this study will help to understand the complexity and susceptibility of the various morphometric factors arises while dealing with different data acquisition and processing techniques. The study suggests that SRTM-GL1 performs better in terms of drainage delineation and basin morphometry, followed by AW3D30, CartoDEM-V3.1 and GDEM-V2 when compared with SOI toposheet-derived terrain attributes.

Assessing the Rate of Shoreline Changes of Rameswaram Island, Tamilnadu, India, using MATLAB Component Runtime Utility & Digital Shoreline Analysis System

The Present study highlights the changes in the coastal tract of Rameswaram island located between the geometric location, latitude 9° 10' to 9° 20' N and the longitude 79° 12' to 79° 30' E. Using Geospatial Technology, Long-term changes have noticed from digitized shorelines taken from Landsat imageries and SOI toposheet for the years 1968, 1978, 1988, 1999, 2009 and 2018. Digital Shoreline Analysis System (DSAS) an extension provided by USGS for ArcGIS used to cast transects perpendicular from the baseline, towards the shorelines. High water Line (HTL) has taken as shoreline in this study. The distance between the shorelines has taken from the cast transects plotted from the baseline. For the rate of change calculation, MATLAB component runtime utility for ArcGIS has used. Based on the Linear Regression Rate (LRR) the shore has classified into High Erosion, Low Erosion, Stable and Low Accretion, High Accretion zones. The island has a shoreline length of 78.4 km, and the studies found that 27.83 km (35.41%) of shoreline is accreting nature, 37.90 km (48.21%) of shoreline is stable, and 12.86 km (16.36 %) of shoreline tends to erode. During the field investigation identified that High amount of erosion occurred in the locations near Pamban, Tharavaithopu and Dhanushkodi. Also, Accretion identified over the locations Ayyanthopu, Natarajapuram and Arichumanai tip. Wind action is one of the physical parameters that induced the erosion in some location of this study area.

Assessing the oscillation of channel geometry and meander migration cardinality of Bhagirathi River, West Bengal, India

Lateral migration of the Bhagirathi River temporally creates unavoidable geomorphic hazards in West Bengal, India. The Bhagirathi River flows SW for ~67.30 km between the confluence point of Ajay and Jalangi rivers in East Burdwan and Nadia districts of West Bengal. The course of Bhagirathi is notably migration prone and cultivates problematic changes along its course over time. In the study, we have looked into its migration tendency and unpredictability for past 238 years and then predicted the lateral shifting of river centerline using temporal satellite imageries — Landsat-5 (TM) of 1987 (8, December), 1995 (28, January), 2005 (7, January) and LISS-IV satellite imagery (2017, 5 January);SOI Toposheet — 1968–1969 (79A/2, 79A/3, 79A/6 and 79A/7) and Rennell’s map of 1779. Other highlights are the quest of fluvial features, oxbow lakes, mid-channel bars, channel migration rate, meander geometry, channel sinuosity in different parts of river course and the parts that experience intensive bank erosion. The entire river course has been subdivided into three segments; viz. reaches A, B and C. Investigation displays that degree of sinuosity decreases from its anterior course (1968) to the existing course (2017). Reach-specific outputs display that reach B is highly sinuous (SI value 1.94 in 2017) and SI increases temporarily, whereas for reaches A and C it decreases with time. The rate of migration is higher in reach B than that in reaches C and A. The study displays a notably decreasing trend of migration in comparison with its previous lateral migration and shows that the migration nature over time is intensively inconsistent and unpredictable except very few portions of the river course. The nature of deposition within the river channel shows an unstable behavior during the entire period of the study. Meander geometry depicts a rapid change of river course innate to meander bends and shows a higher rate of migration by meander loop cut-off rather than lateral migration that reflects the inconsistency, erosion vulnerability and unpredictable nature of migration. The present work offers a valuable source to comprehend channel changes in Bhagirathi River and serve as an efficacious base for river-bank migration and erosion hazard planning and management.

Recognition and Mapping of Structural Guides for Barytes Mineral Exploration in Parts of Kadapa District using Remote Sensing and GIS

Identification and mapping of structural criteria of a region reveals information about the occurrence of ore deposits of igneous and metamorphic origin. Remote Sensing and GIS data helps in detection of such structural features, like faults, lineament, folds, etc. These are important guides for exploration of ore mineral and groundwater. Kadapa district hosts important ore minerals of igneous and metamorphic origin like Barytes, asbestos, gold, galena, steatite etc. Barytes is exploited in the district since a long past. Present study is taken up to prepare structural map along the existing Barytes mines in the district using geospatial techniques like Remote Sensing and GIS, with an intension to identify new Barytes mineralized locations through these structural guides. The structural data of any region provides a quick payback with faster, more accurate mineral identification for gold, silver, diamonds, iron, nickel, copper, uranium, aluminum, Barytes, and also provide rock and mineral relationship in search for ore deposits during exploration. Structural criteria, is an important measure in mineral exploration of certain mineral deposits that are confined by geographic, geological and tectonic features. Mainly the occurrence of ore deposits is dependent on neighboring lithology and structural deformation of the location area. Endogenous mineral deposits like tin, muscovite, lithium, tungsten, gold, beryl, gemstones etc. are associated with intermediate and acid rocks like syenite; granite, granodiorite. etc., and deposits of copper, nickel, cobalt, silver, arsenic and apatite are formed in basic rocks like gabbro, norite, diorite, etc. Due to false nature of ore bodies and their varied controls of mineralization the techniques used for mineral exploration such as remote sensing followed by ground and airborne geophysical surveys, stream sediment, litho-geochemical surveys and core drilling have been used for regional and detailed surveys. The aspect that indicate the mineralisation are known as localizers. If these indicators can be identified on satellite data/imagery then the mineral explorations can be much faster with increased efficiency. Keywords: Multispectral, LISS-III Satellite Imagery, SOI Toposheet remote sensing, GIS Cite this Article Ramachandra M., Raghu Babu K., Pradeep Kumar B. et al. Recognition and Mapping of Structural Guides for Barytes Mineral Exploration in Parts of Kadapa District using Remote Sensing and GIS. Journal of Remote Sensing & GIS . 2018; 9(3): 30–36p.

IDENTIFICATION OF LANDSLIDE SUSCEPTIBILITY ZONATION IN CNG GHAT SECTION, GUDALUR, THE NILGIRIS – USING GIS BASED ANN/MULTI CRITERIA METHOD

Abstract. Among the various natural hazards, landslide is the most widespread and damaging hazard. In recent times, throughout a lot of attention is being drawn to evaluate the risk due to landslides. The invention of remote sensing and GIS have been new vistas in the field of geo scientific studies viz. geomorphological mapping, groundwater potential mapping, disaster management etc. The present study has been undertaken to study different thematic maps like, contour, drainage, slope, aspect, curvature, DEM, DTM, drainage density, drainage intensity, geology, lineament, lineament density, lineament intensity, geomorphology, land use, weathering thickness, run off, soil thickness and buffer maps like road, drainage, lineament etc. in CNG ghat section, Gudalur, The Nilgiris. For this purpose, the satellite image IRS – RS2, LISS III January 2014 used to prepare different thematic maps. The contour, drainage and road network were incorporate from SoI Toposheets. The slope, curvature, aspects and buffer maps were prepared from GIS environments. Based on field studies, above said thematic maps (22 nos.) were prepared and were grouped into 3 categories viz. Geology, Hydrology and Terrain. In each category the input maps were assigned different score as well as each layer has been given different weightage. Finally the categories are analysed through multi – criteria analysis to find out 5 different vulnerability classes. The 5 different land susceptibility zones are classified as very low, low, moderate, high and very high. The percentages of area under different susceptibility classes are 3%, 20%, 51%, 25%, and 1% respectively. The locations of small area major landslides and slip locations were calculated from different years using (2010 and 2014) Trimble GPS in the field. The field data was converted into point layer in GIS and landslide inventory map was prepared. This map was superimposed in landslide susceptibility zonation map. As per field data 0%, 9.25%, 57.5%, 32% and 1.25% Slide points are come under very low, low, moderate, high, very high susceptibility zones respectively.

TEMPORAL MONITORING OF GLACIER CHANGE IN DHAULIGANGA BASIN, KUMAUN HIMALAYA USING GEO-SPATIAL TECHNIQUES

Abstract. Present study is based on the change in surface area of the glaciers in downstream area of Dhauliganga basin, Pithoragarh district, Uttarakhand. For this study, Survey of India toposheets (surveyed in 1963) have been used for preparation of initial boundary of glaciers. Total 11 glaciers have been selected for the study in downstream valley. RGI (Randolph Glacier Inventory) data version 60. (15_RGI 60.SouthAsiaEast) from GLIMS, released July 28 2017, used for measuring temporal change in surface area. Landsat 8 OLI/TIRS image of 06 November 2016 has used to measure present area of glaciers. ASTER GDEM was used for automatic extraction of basin boundary by hydro-processing methods. Glacier boundaries were manually digitised from the Landsat image for better accuracy. The total glacier area was 69.35 km2 (1963), 48.10 km2 (2001) and 34.35 (2016) as determined from SOI toposheet, GLIMS and the Landsat image of 2016 respectively. Total vacated area by the retreat and melting of glaciers from 1963 to 2016 is 35 km2, which accounts to a total loss of 50 % from the total glaciated area. Google Earth imagery was also considered for marking the actual position of glacier outlines. Ice walls in topographic maps are also considered as the part of glacier but in present satellite image they are free from ice.

Assessment of Land Use/Land Cover Changes in Coimbatore North Taluk, Tamil Nadu, India using GIS and Remote Sensing

The main aim of the present study is to assess Land use/land cover changes in Coimbatore North Taluk for the period of 2001 and 2018. The study area is located in Coimbatore district, Tamil Nadu state and geographical area is 479.5 km2. To analyze land use/land cover changes, a temporal satellite images Landsat 7 (2001) Sentinel-2 (2018) was used. Vector data for the study area was extracted from the SOI toposheets and taluk sheets. The above satellite image was classified into four major classes viz. water bodies, croplands, built-up area, and forest using hybrid supervised classification method. ERDAS Imagine 2015 and ArcGIS 10.5 software’s were sued to classify the satellite image and assess the land use/land cover changes for the above periods. The land use/land cover change detection analysis revealed that built up area was increased compared to 2001 and all other classes decreased. Urbanization is the primary cause of the land use and land cover changes for the study area.

Geomorphometric analysis and terrain evaluation for environmental management in the Kurseong hill subdivision of the Darjeeling district, West Bengal, India

Kurseong hill subdivision of the Darjeeling district, West Bengal, is associated with complex geomorphic set-up stemmed from form–process interaction on varied slope, relief, elevation, aspects, ridge–valley orientation, density and frequency of drainage, dissection, ruggedness and topographic wetness over different stratigraphy of geological rocks having different hardness. This complexity provides ample scope to evaluate the terrain and categorize the terrain into different sensitivity zones according to land utilization point of view so that different terrain segments can be classified into different grades and therefore can be rationally utilized and managed for sustainable use. Therefore, the present paper takes an attempt to evaluate the terrain sensitivity of the Kurseong hill subdivision based on multi-criteria analysis method to identify different grades of terrain according to their ability to hold and sustain the pressure of land utilization for settlements, agriculture and other land uses. Terrain sensitivity evaluation of the Kurseong hill subdivision has been done on the basis of the study of hard rock geology, some selected geomorphometric parameters derived from 3-arc-second SRTM digital elevation data as well as SOI toposheets having RF of 1:50,000 and the existing land use factors after necessary ground truthing on some selected sites. The procedure adopted for multi-criteria analysis is 1 km2 grid-based rating value assignment algorithm of the selected parameters and determination of different classes of sensitive terrain and their gradation according to the capacity of the terrain to withstand present pressure of land utilization. Some measures for rational land utilization and management have also been proposed for optimal land use planning for the study area.