SRTM DEM Research Articles

Integration of TanDEM-X and SRTM DEMs and Spectral Imagery to Improve the Large-Scale Detection of Opencast Mining Areas

Land use and land cover (LULC) is a key variable of the Earth’s system and has become an important indicator to evaluate the impact of human activities on the Earth’s ecosystems. With the increasing demand of mine resources, widespread opencast mining has led to significant changes in LULC and caused substantial damage to the environment. An efficient approach of detecting mining activities at large scales is of critical importance in mitigating their potential impacts on downstream settlements and in assessing LULC characteristics. In this study, we present a novel approach for enabling large-scale automatic detection of opencast mining areas by integrating multitemporal digital elevation models (DEMs, including the SRTM DEM and the recently released TanDEM-X DEM) and multispectral imagery in object-based image analysis and random forest (RF) algorithms. A sequence of data preparation, image segmentation, threshold analysis, calculation of metrics, and influence factor regulation was developed and tested on the Landsat 8 sample dataset in Inner Mongolia in China, which is a mineral-rich area. Aside from spectral metrics, such as brightness and reflectance value, introduced topographical features enhanced the modeling and classification significantly, and the overall performance is greatly influenced by feature selection (the out-of-bag error rate in the RF algorithm is 7.54% for the integrated DEM method in comparison with 12.70% for the only-optical images method). The integrated use of spectral imagery and multitemporal DEMs reveals that the identified mining area is about 1100 km2 in the study area and period, and the topographic changes of opencast mining in terms of elevation difference is between −258 and 162 m. The results show that the method can map the locations and extents of mining areas automatically from spectral and DEM data and can potentially be applied to larger areas.

Original

The evolution and development of a drainage network largely depends upon the surface topography of a landscape. Even topographic attributes such as overland flow, sub-surface flow, stream flow etc. are highly determined by the relief and slope aspects of the basin area. Topography influences evolution of landforms, soil development, vegetation growth, types of settlement, agricultural pattern etc. So it becomes very important to quantify different topographical parameters so that proper watershed management can be done. This work is an attempt to evaluate existing topography of study area using topographical sheets and SRTM DEM data. For calculation and analysis of data MS Excel is used while Geographical Information System (GIS) is used for mapping purpose. Present work provides better understanding of surface and relief aspects of landforms in Lower Barakar basin.

Discharge Estimates for Ungauged Rivers Flowing over Complex High-Mountainous Regions based Solely on Remote Sensing-Derived Datasets

Reliable information about river discharge plays a key role in sustainably managing water resources and better understanding of hydrological systems. Therefore, river discharge estimation using remote sensing techniques is an ongoing research goal, especially in small, headwater catchments which are mostly ungauged due to environmental or financial limitations. Here, a novel method for river discharge estimation based entirely on remote sensing-derived parameters is presented. The model inputs include average river width, estimated from Landsat imagery by using the modified normalized difference water index (MNDWI) approach; average depth and velocity, based on empirical equations with inputs from remote sensing; channel slope from a high resolution shuttle radar topography mission digital elevation model (SRTM DEM); and channel roughness coefficient via further analysis and classification of Landsat images with support of previously published values. The discharge of the Lhasa River was then estimated based on these derived parameters and by using either the Manning equation (Model 1) or Bjerklie equation (Model 2). In general, both of the two models tend to overestimate discharge at moderate and high flows, and underestimate discharge at low flows. The overall performances of both models at the Lhasa gauge were satisfactory: comparisons with the observations yielded Nash–Sutcliffe efficiency coefficient (NSE) and R2 values ≥ 0.886. Both models also performed well at the upper gauge (Tanggya) of the Lhasa River (NSE ≥ 0.950) indicating the transferability of the methodology to river cross-sections with different morphologies, thus demonstrating the potential to quantify streamflow entirely from remote sensing data in poorly-gauged or ungauged rivers on the Tibetan Plateau.

Change detection of glaciers and snow cover and temperature using remote sensing and GIS: A case study of the Upper Indus Basin, Pakistan

Glaciers and snow cover in the Himalayas, Karakoram, and Hindu-Kush (HKH) mountain ranges are expected to decrease, resulting in serious consequences in terms of water availability for downstream population. This study is an attempt to detect temporal trend of snow cover in the Upper Indus Basin (UIB), in northern Pakistan, with respect to temperature change, spatial variation in land surface temperature, and to evaluate the accuracy of Landsat imagery for detecting land surface temperature. Landsat images, acquired for the period 1993 to 2019 and the Normalized Difference Snow Index (NDSI), were used to map the snow cover. Maximum snow cover of about 20,675 km2 was observed in April 2017 followed by 1996, and 1999, when it was about 18,800 km2; the minimum of about 14,500 km2 was recorded in April 1993, 2011 and 2018. The results show that there has been a very slight increase in snow cover area with time. The maximum elevation of snow-covered area, extracted from the Digital Elevation Model of Shuttle Radar Topography Mission (SRTM DEM) in the study area, is 7889 m while the minimum elevation is 991 m. Freezing temperature occurs above 3000 m elevation, indicating that these areas are covered by snow and glaciers for much of the year. Temperatures, of −20 °C to −25 °C, were present only at a few places–at the very high elevation of above 6000 m. We found inconsistencies in the Landsat temperature data, which were corrected using in-situ daily temperature data. Validation of Landsat extracted temperatures before and after using the in-situ daily temperature data improved the accuracy and removed the inconsistencies. We recommend use of in-situ diurnal temperature data to correct Landsat extracted temperature data.

Watershed prioritization for soil and water conservation aspect using GIS and remote sensing: PCA-based approach at northern elevated tract Bangladesh

The current study has been derived to understand morphometric parameters to pledge the reduction in the proclaimed drought influence for climate change. Watershed prioritization has been studied using the geographical information system and remote sensing techniques for soil erosion and water preservation measure at Plio–Pleistocene elevated tract in Bangladesh. Secondary data, i.e., SRTM DEM and the topographical sheets, have been used for the drainage network identification. Seventeen watersheds of fifth order and three watersheds of sixth order are selected for the whole study. Sixteen basic morphometric parameters that are categorized as areal, linear and relief aspects have been used for the study area. The study area comprises sixth stream order that has been obtained using a stream threshold value of 100-m length. Morphometric analysis is suitable for water and soil conservation practice where groundwater and relevant data sets are not available. For the categorization and correlation of the morphometric parameters, principal component analysis (PCA) has been used in the present study. PCA analysis is more suitable, well-known and widely used method for its simplicity to choose more influencing parameters (correlated parameters) that are responsible for watershed prioritization. Strongly correlated components (Dd, Rc, Re and Rb) are used for the compound parameter (Cp) and final priority (Rp) calculation. Low Cp value is suitable for water and soil conservation measure. Therefore, the corresponding low Cp has been taken as one for final priority ranking (Rp) purpose, then second lowest value as two, and so on.

Application of Time Series InSAR (SBAS) Method using Sentinel-1A Data for Land Subsidence Detection in Surabaya City

We studied land subsidence occurrence in Surabaya, considering the rapid urban growth in the city. It is evidenced by the increasing number of buildings (e.g., houses, apartments, offices) that have been realized before 2015 and the increasing transport activities in the industrial area. Land subsidence is a vertical deformation on the land surface that can be caused by landslides, earthquakes, soil consolidation process, or even human-made activities, depending on the material characteristics of the area. In this study, Time-series InSAR (TS-InSAR), specifically the Small Baseline Subset (SBAS) method, is applied to obtain the Line-of-Sight (LOS) velocities and time-series LOS displacements in Surabaya between May 2015 and September 2017. We used 28 Sentinel-1A data (IW mode) acquired by using Terrain Observation with Progressive Scan (TOPS) operation with the spatial resolution of 5 ´ 20 m and covers the area of 250 km2. DEM SRTM with 30 m spatial resolution was used to reduce topography effect contribution in the interferograms. Based on the SBAS method, interferogram pair selection is applied with the maximum value of 150 m for the perpendicular baseline and 100 days for the temporal baseline. The DInSAR process successfully generated seventy-four (74) interferogram pairs, and then by using SBAS algorithm, the LOS velocity and time-series LOS displacement were estimated. The results showed the varying displacements respond with the significant subsidence occurred in the North, East, and Southeast part of Surabaya. The SBAS result confirmed that the LOS velocity over the Surabaya area between May 2015 and September 2017 ranges from -40 to +30 mm/year. Significant land subsidence occurred in the Asemrowo area (North Surabaya) with the value of LOS displacement velocity up to -45 mm/yr.

ANALYSIS AND COMPARISON OF SRTM3 DEM AND ASTER GDEM V2

Abstract. Global Geographic Information Resources Construction and Maintenance Renewal Project is in urgent need of digital elevation model worldwide. At present, the errors of ASTER GDEMv2 and SRTM3 DEM data widely used are unevenly distributed. In this paper, high-precision and high-resolution WorldDEM data are taken as true values, and flat areas in Turkey and alpine region in Nepal are selected respectively as two test areas A and B. The vertical accuracy of ASTER GDEMv2 and SRTM3 DEM data is verified and compared by using DEM elevation difference numerical analysis, spatial differentiation analysis, slope spectrum curve and other methods. The results show that the two digital elevation models in flat terrain conform to the nominal accuracy, and the vertical accuracy of SRTM3 DEM has an advantage, while the vertical accuracy of ASTER GDEMv2 in high elevation area with large terrain fluctuation is obviously higher than that of SRTM3 DEM , and the area of SRTM3 DEM data accuracy exceeding nominal accuracy is larger. On this basis, the applicability of the two kinds of DEM is analyzed. It is concluded that SRTM3 DEM data with better accuracy should be selected in low altitude plain areas, ASTER GDEM data with higher resolution should be given priority in hilly areas with complex terrain and high mountain areas with severe topographic fluctuations, and ASTER GDEM data can be used to supplement the uncovered areas of SRTM3 DEM。In addition, in areas with high vegetation coverage, the accuracy of the two data is greatly affected, which can be supplemented by ICESAT/GLAS and ICESAT2/GLAS data with strong vegetation penetration ability. The results can provide scientific basis and data support for global space information projects.

Glacier Variations at Xinqingfeng and Malan Ice Caps in the Inner Tibetan Plateau Since 1970

The inner Tibetan Plateau is a glacierized region where glaciers show heterogeneous change. The Xinqingfeng and Malan ice caps are located in this region, and a transition zone exists with shifting influences between the westerlies and Indian summer monsoon. However, there is a lack of detailed information regarding glacier area and mass changes in this region before 2000. In the present study, we describe an integrated view of the glacier area and its mass changes for Mt. Xinqingfeng and Mt. Malan as derived from topographic maps, Landsat, ASTER, SRTM DEM, and TerraSAR-X/TanDEM-X from 1970 to 2012 and from 1970 to 2018, respectively. Our results show that the glaciers experienced a slight shrinkage in area by 0.09 ± 0.03% a−1 from 1970 to 2018 with a median mass loss rate of 0.22 ± 0.17 m w.e. a−1 and 0.29 ± 0.17 m w.e. a−1 between 1999 and 2012 at Mt. Xinqingfeng and Mt. Malan, respectively. The glaciers of Mt. Malan had a total mass loss of 0.19 ± 0.14 m w.e. a−1 during the period 1970–1999. A minimum of seven glaciers at Mt. Xinqingfeng and Mt. Malan showed heterogeneous variations with either surging or advancing during the observation period. Among them, the West Monuomaha Glacier, Monuomaha Glacier, and Zu Glacier were identified as surging glaciers, and the others may also be surging glaciers, although more evidence is required. These glaciers showed a long active period and low velocities. Therefore, we suggested that thermal controls are important for surge initiation and recession.

Identification of Groundwater Potential Zones Using RS, GIS and AHP Techniques: A Case Study in a Part of Deccan Volcanic Province (DVP), Maharashtra, India

This article deals with the remote sensing and geographic information system techniques in assessing groundwater potential zones by the manipulation and analysis of the individual layer of spatial controlling data in a part of Deccan Volcanic Province, Maharashtra. Available geology, geomorphology, and soil maps were collected. Land use and land cover (LULC) and Lineament maps had been prepared using the LANDSAT-8 (TM and OLI) Satellite Image (November 2015). The SRTM DEM (resolution: 30 m) data had been employed for the preparation of slope and drainage maps. These maps were converted into the raster format. Analytic hierarchy process was applied to weight, ranking, and reclassify these maps in the ArcGIS version 10.4. Then, groundwater prospect map had been prepared by overlaying the maps. The results show that five groundwater potential zones such as very poor (11.77%), poor (21.73%), moderate (30.13%), good (25.34%), and very good (11.02%) exit. Sensitivity analysis reveals that the lineament density, LULC, and slope increase the area slightly only in the very poor to poor potential zones. Besides, the well yields, groundwater level fluctuation corresponding rainfall data had been utilized to validate. The yield values vary from 5.94 to 14.88 l/s in the good to very good potential zones, whereas 0.38 to 1.37 l/s within the poor to very poor potential zones. In addition, cross-correlation coefficients among groundwater level and rainfall is well-related to the groundwater potential index (R2 = 0.84), which will help to construct artificial recharge structures and the planning of sustainable groundwater management.

Analysis of the area affected by the tsunami in Pandeglang, Banten: a case study of the Sunda Strait Tsunami

Pandeglang District becomes a concern because one of the locations had an impact on the Tsunami on December 22, 2018. Its position in the western waters and directly facing the Anak Krakatau Volcano is very potentially vulnerable. The Tsunami triggered by the volcanic activity of Anak Krakatau Volcano, mountain avalanche material. Evaluation regarding coastal land affected is also needed to anticipate future disasters. The study of the coastal areas affected by extraordinary events, such as the Tsunami, was carried out by stakeholders in evaluating coastal land to be more responsive to disasters. Three sub-districts with different morphology selected as samples of the affected areas, Labuan, Sumur, and Panimbang. We used highresolution Sentinel 2.0 images and Elevation Model Data (SRTM DEM) with unsupervised classification method to perform analysis of the area affected by Tsunami condition on coastal features. The results showed that the area affected especially the low land, as open land area at Labuan Sub-district was 189,298 Ha, Sumur Sub-district, 144,837 Ha, and Panimbang Sub-district was 282.852 Ha. Varied inundation range 50 - 200 meters from the coastline. The elevation of the three sub-districts shows vulnerable areas with an elevation of <2.5 m to 0.5 m above sea level.

A Multi-Dimensional Approach to Revealing Causes of Pavement Failures: Case Study of Minna – Suleja Highway, North-Central Nigeria

Remote sensing, geotechnical studies and geophysical data have been applied to determine the causes of the continuous pavement failure of the Minna – Suleja highway in a part of North-Central Nigeria. In this study, remotely sensed data in the form of Landsat 8 OLI and SRTM DEM were processed to extract structural lineaments and drainage pattern of the area. Geotechnical evaluation of soil samples such as grain size analyses, Compaction Test, Atterberg Limits and California Bearing Ratio (CBR) determination were also conducted. Geophysical data acquired were in the form of lateral resistivity profiling data at 500 m intervals and twenty-one Vertical Electrical Sounding (VES) spread across the selected sections of the road. Lineament analysis revealed predominant NNE-SSW trending structures. A notable percentage of the Lineaments trend NW- SE. Both sets of lineaments constitute a conjugate fracture system. CBR values in both portions range from 5 – 15% in soaked condition and unsoaked condition at OMC. Plasticity index range from 14 – 30 and 19 – 45 in both portions. Quantitative interpretation of the VES results established the presence of mostly three geologic layers which are: Clayey top soil, sand/lateritic sand and weathered basement. Resistivity values range from 20 Ωm to 300 Ωm for the top soil layer. The depths of this layer were generally less than 3 m. Preponderance of intersections of lineaments along failed portions account for near surface fractures, making these zones weak. This can be linked to low resistivity of the near surface materials and shallowness of the water bearing zones especially on the failed portions on which the road pavement foundation was laid. A distinction could not be made on the results of the geotechnical properties in both the failed and stable portions of the road. Hence, failure factors are not linked to the geotechnical properties of the soils.

VALIDACIÓN DE MODELOS DE ELEVACIÓN DIGITAL EN LOS ANDES CENTRALES DE CHILE: ANÁLISIS DE LA EXACTITUD Y PRECISION VERTICAL A ESCALA REGIONAL Y LOCAL CON DATOS GNSS Y LASER

This study validated the vertical exactitude and accuracy of seven digital elevation models DEM (SRTM X-SAR, SRTMv3 void voided 1 arcsec, SRTMv3 void filled 3 arcsec, SRTM GL1 Ellip, Aster GlobalDEM v3 2019/08. Alos World 3D 30m v21 2018/04,TamDEMx), considering both regional and local scale in middle/ higher mountain areas of the central Andes of Chile. Exactitude and Accuracy were determined using metrics and/or statistical tests reviewed by the National Institute of Standardization (INN), tests that considered the elevation data of 149 ground control acquired trough several GNSS surveys, and 1825 gcp provided by IceSat-2 mission records. At the regional scale, the results of the error estimation between the observed and the predicted value indicate that the DEM SRTM X-SAR is the most precise and vertically accurate set (21,3 m of exactness equivalent to 85% of exactitude; RMSEz = 21,7 m of precision equivalent to 86.8% of accurate). However, the band layout does not allow calculations that ensure the completeness of an area greater than 2500 sqkm. Then, the next option is the DEM Alos World 3D 30m v21 2018/04 (22,5 m of exactness representing 90% of exactitude; RMSEz = 23 m equivalent to 92% of accurate). Locally, and first considering the entire area and all IceSat-2 data, and then only those measurements in stable zones, in both cases the Alos World 3d is the most exactly and vertically accurately DEM, followed by the DEM AsterGDEMv3 19/08. The poorest indicators belong to the DEM TamDEMx

Landslide Hazard Zonation from a GIS Perspective and Urban Planning Solutions in Central –Division of Fiji Islands

As is a characteristic of rainfall-induced surficial landslides, the mass movement occurred where the landform or configuration of the bedrock surface facilitated the concentration of slope water. More than half of the landslides originated in slope depressions or drainage lines, with initial failure taking place on an upper slope, ridge or summit. The present study aims at assessing the rainfall intensity, site-soil-geology and seismicity of the central division of Viti Levu, Fiji Islands using the GIS and remote sensing techniques. Rainfall intensity, Site-soilgeology, geomorphology and SRTM DEM data were the main sources of layers used to carry out such analysis using the Frequency Ratio methodology and ArcGIS Multi-Criteria Analysis (MCA). The final result of Land Slide Potential Zone (LSPZ) indicates the ‘low’, ‘moderate’ and ‘high’ zones. The result presents a readable map for people to simply identify their state of vulnerability within the study area. Thus, this research will assist professionals such as urban planners, engineers and legislators to implement sustainable developments whilst reducing the risks of disasters.

Fluoride dynamics in hydrogeological diversity and Fluoride Contamination Index mapping: a correlation study of North Singbhum Craton, India

Fluoride is a colourless micro-nutrient which is highly required for the strong teeth and bones. The above and below the prescribed range (0.6–1.5 mg/l) of fluoride in drinking water is harmful or hazardous for human health. Granite gneiss and pegmatite are the natural sources of fluoride minerals in this North Singbhum Craton. Purulia district which is the extended part of Chhota Nagpur Gneissic complex hosts such fluoride bearing rocks and minerals. About 619 water samples were collected from different parts of the district. Different rock samples have been collected from exposed litho-strata with prominent geological structures through Garmin GPS Etrex 30x. Sample sites have been geocoded on SRTM DEM and rocks are tested in the laboratory to examine the concentration of fluoride ions. The study was conducted to identify the natural and anthropogenic sources of fluoride and find out the relationship among the fluoride, geology with structures, hydro-geomorphology, soil and aquifer. Lineament features have been extracted using different bands of two specific images, namely ETM and ASTER. Digital mapping techniques including spatial analysis are used to detect the geomorphological attributes using SRTM and ASTER DEM data with adequate ground verification. Finally, Fluoride Contamination Index (FCI) map has been prepared by Thomas L. Saaty (1984) Analytical Hierarchy Process (AHP) using weighted sum method (WSM) in the range between 1 and 10 on the basis of their percentage of contamination. The study shows that high and very high fluoride content (3.52–5.50 mg/l and more than 5.50 mg/l) is found in the undulating plateau with dissected valley while granite gneiss and pegmatite are the dominant fluoride bearing rocks. Fluoride minerals are being released from structural weak zones through various mobile agents and ultimately mixed into the soils and groundwater. The high and very high contaminated zones (37.79%) reveal moderate to good groundwater yield pockets of unconfined and semi-confined aquifers and larger population of these regions are exposed to fluoride vulnerability.

Earthquake Hazard Micro Zonation in Fiji Islands: A Research of Viti Levu Island

Depending on magnitude the earthquake hazards can have collateral retort of devastations in collusion with the site-soil geology. Fiji – Tonga region accounts for about 70 percent of the world’s earthquakes with depths greater than 400 kilometres. Risk management through spatial planning is paramount for tectonism linked disasters in order to reduce the extent of fatality and economic cost. Humanity is at the ‘tipping point’ of self-destruction unless knowledge on disaster risk reduction is disseminated on time in the form of implementable solutions such as using ArcGIS as a tool to provide worthwhile segmentation of disaster prone zones to administrators. The present study aims at assessing the site-soil geology and earthquake hazard potentiality of VitiLevu Island using the GIS and remote sensing techniques. Site-soil geology, geomorphology, seismology and SRTM DEM data were the main sources of layers used to carry out analysis using the Saaty’s Analytical Hierarchical Process (AHP) and ArcGIS Multi-Criteria Analysis (MCA).The technology involves preparing and assessing several contributing factors (thematic layers) those are assigned with weightage and rankings, and finally normalizing the assigned weights and ranking. In the ArcGIS 10.5 spatial analyst tool, the raster calculator, reclassify and weightage overlay tools were mainly employed in the study. The final output of EHZ indicates the ‘low’, ‘moderate’ and ‘high’ zones of potential earthquake disasters. The result provides a substantial readable guide for urban and regional spatial planners as well policy makers to formulate disaster reduction policies. Thus, informing civil societies, private societies and community to become well - versed with adaptive strategies suitable to withstand and encounter earthquake hazards.

Prioritization of Sub-Watersheds for Soil and Water Conservation in Parts of Narmada River through Morphometric Analysis Using Remote Sensing and GIS

ABSTRACT GIS-based prioritization of sub-watersheds of Hoshangabad and Budhni industrial area, Madhya Pradesh, India were carried out to describe the importance of morphometric parameters in the field of water and soil conservation. In the study, four subwatersheds were prioritized through geomorphologic analysis for soil and water conservation. Topographic maps 55 F/9, 55 F/10 and 55 F/13 on scale 1:50,000 were used to evaluate the drainage characteristics of watershed. SRTM DEM data has been processed for slope analysis and delineation of sub-watersheds. LISS-III, IRS data was processed for land use/ land cover analysis. Soil map has been generated by processing of NBSS &amp; LUP soil map. The various morphometric parameters evaluated in each sub-watershed includes drainage network, drainage geometry and texture analysis and relief parameters in ArcGIS. Each sub-watershed has been prioritized by assigning ranks using compound parameter. After prioritization, land use, soil type and slope classes of each subwatershed were integrated to propose suitable soil and water conservation structures at appropriate places. It has been suggested that the proposed soil and water conservation structures must be executed on priority basis to reduce the adverse effect on the land and environment. The study shows that classification and prioritization of sub-watersheds are very relevant, supportive and useful in the watershed, where there is high diversity in agricultural practices, soil texture and land cover. Thus, priority wise execution of the proposed soil and water conservation structures will not only reduce the soil erosion but also increase the surface and groundwater availability in the area. Therefore, prioritization of these sub-watersheds is found very helpful for soil conservation and management of groundwater in the watershed.

Application of Remote Sensing, GIS and Hydrogeophysics to Groundwater Exploration in Ogun State: A case study of OGD-Sparklight Estate

With the increase in population of Ogun state, the necessity to provide water to the populace has become a disturbing problem. In this study, a systematic approach to delineate the groundwater potential zones of the state was carried out using Remote Sensing, Geographic Information Systems (GIS) and Hydrogeophysics as a tool. Vertical Electrical Sounding (VES) observations were also carried out in OGD Sparklight Estate to validate the results obtained from the integrated remote sensing and GIS observation and also determine the aquifer depth and possible pollution. The various thematic maps such as: soil map, land use/Land, geological map, rainfall map, lineaments map were obtained from enhanced satellite imagery and Slope map was generated from Shuttle Radar Topographic Mission elevation model (SRTM DEM). These maps were overlaid in terms of weighed overlay method using Spatial Analysis tool in Arc GIS 10.4. During weighed overlay analysis, different ranks were given to each individual parameter of each thematic map and weights were assigned according to their influence. The groundwater potential map obtained from the study area showed that 47% of the total study area (Ogun state) lie within the “very high” potential zone, 15% of the area falls within the “high”, 30% lies within the of “moderate” zone, 5% lies within the “low “potential zone while “2% “ lies within the very low potential zone. The very high potential areas lie within the sedimentary zone in the southern part of the study area with high alluvial deposits, while the “very low” prospect zone lies majorly within the basement complex zone in the northern part of the study area. The boreholes susceptible to salt water intrusion were identified and the best drilling point with respect to depth were also determined.

Analysis of Climate Change in the Area of Vojvodina-Republic of Serbia and Possible Consequences

Climate change conditions a wide range of impacts such as the impact on weather, but also on ecosystems and biodiversity, agriculture and forestry, human health, hydrological regime and energy. In addition to global warming, local factors affecting climate change are being considered. Presentation and analysis of the situation was carried out using geoinformation technologies (radar recording, remote detection, digital terrain modeling, cartographic visualization and geostatistics). This paper describes methods and use of statistical indicators such as LST, NDVI and linear correlations from which it can be concluded that accelerated construction and global warming had an impact on climate change in period from 1987 to 2018 in the area of Vojvodina – Republic of Serbia. Also, using the global SRTM DEM, it is shown how the temperature behaves based on altitude change. Conclusions and possible consequences in nature and society were derived.

Analysis of Parabolic Dune Morphometry and Its Migration in Thar Desert Area, India, using High-Resolution Satellite Data and Temporal DEM

Thar Desert region is mainly comprised of sand dunes and sand sheets which are distributed in more than 80 per cent geographical area of western Rajasthan. Among the different types of sand dunes, nearly 50 per cent area of western Rajasthan is covered by parabolic dunes. However, morphodynamics of parabolic dunes in the Thar Desert is not fully understood. For this purpose, high-resolution satellite data of IRS RS2 LISS-IV (5.8 m resolution) and Cartosat-1 DEM (10 m resolution) have been used for delineation of parabolic dunes with the derivation of morphometric parameters (dune length, dune area, volume of sand accumulation and dune height) in western Rajasthan. Scatter plots of these morphometric parameters show a linear relationship with correlation coefficient (0.59–0.80). Interpolated maps show an increased rate of wind speed during 1980–2014. Although several measures have been taken for sand dune stabilisation, differential sand migration has been estimated for selected parabolic dunes using temporal DEMs (SRTM DEM of 2000 and Carto DEM of 2009). The analysis shows average dune shifting of 7.11 m/year in Barmer, 5.15 m/year in Jaisalmer and 3.51 m/year in Bikaner districts of western Rajasthan in the Thar Desert area.

A GIS-based assessment of recent changes in drainage and morphometry of Betwa River basin and sub-basins, Central India

Morphometric characterization of the Betwa River basin (BRB) in Central India has been carried out to understand the spatial variations in morphometric parameters and evaluate hydrological, geological and topographical characteristics by analyzing SRTM DEM and topographical maps using geographic information system. Based on catchment characteristics and anthropogenic activities, the Betwa River basin and sub-basins were divided into three regions: (a) upstream, (b) midstream and (c) downstreams regions. The BRB comprised a dendritic drainage pattern where the maximum number of the stream was found in the first order. The mean bifurcation ratio (4.61) showed that the drainage pattern was not affected by structural disturbances. The drainage texture analysis showed the dominance of coarse texture, low runoff, low erosional potential, permeable subsurface material, high vegetation cover and low relief. The circularity ratio (0.13) showed an elongated shape of the basin. The > 74.5% of the study area had < 3° slope indicates gentle terrain condition. These results could be utilized in developing watershed management, agricultural land-use planning, forestry management and planning of sustainable industrial facilities.