Search
Search Results
-
Integrated approach for lineament extraction in assessing groundwater potential: a case study in the highlands of Eritrea
1-14Views:156Groundwater exploration is crucial for sustaining ecosystems and human activities, particularly in semi-arid regions like the highlands of Eritrea. This study evaluates the effectiveness of manual and automated lineament extraction methods for identifying geological structures indicative of groundwater potential. Using a 30-meter resolution SRTM digital elevation model (DEM), we generated hillshade images and extracted lineaments manually by ESRI ArcGIS and automatically with MATLAB's edge detection algorithms, including Canny, Sobel, Prewitt, Roberts, Approximate Canny, and Laplacian of Gaussian (LoG). Our findings reveal significant differences between the manual and automated methods. Directional analysis showed that manually identified lineaments primarily followed NE-SW and NW-SE directions. Among the automated methods, Canny, Approxcanny, and Prewitt exhibited similar directional trends. Lineament density maps indicated high-density areas in the western and northern parts of the study area for both manual and automated methods. The LoG algorithm showed the highest correlation (0.8561) with the manual method, suggesting it as a reliable alternative for lineament mapping, contributing to more efficient groundwater exploration in semi-arid regions.
-
Interpolation and 3D visualization of soil moisture
23-34Views:518Adaptation to climate change demands the optimal and sustainable water management in agriculture, with an inevitable focus on soil moisture conditions. In the current study we developed an ArcGIS 10.4. platform-based application (software) to model spatial and temporal changes in soil moisture in a soy field. Six SENTEK Drill & Drop soil moisture sensors were deployed in an experimental field of 4.3 hectares by the contribution of Elcom Ltd. Soil moisture measurement at each location were taken at six depths (5, 15, 25, 35, 45 and 55 cm) in 60-minute intervals. The model is capable to spatially interpolate monitored soil moisture using the technique. The time sequence change of soil moistures can be tracked by a Time Slider for both the 2D and 3D visualization. Soil moisture temporal changes can be visualized in either daily or hourly time intervals, and can be shown as a motion figure. Horizon average, maximum and minimum values of soil moisture data can be identified with the builtin tool of ArcGIS. Soil moisture spatial distribution can be obtained and plotted at any cross sections, whereas an alarm function has also been developed for tension values of 250, 1,000 and 1,500 kPa.
-
GIS-integrated multi-criteria suitability analysis for healthcare facilities site selection in Rajouri district, Jammu and Kashmir, India
12-29Views:320The study aims to develop a Decision Support model for the selection of a suitable site to establish a new healthcare center with adequate facilities based on the analytical hierarchy process (AHP) in the Rajouri district of Jammu and Kashmir. This study utilized AHP and GIS to identify an appropriate location for a new healthcare center. The study employed eight criteria to evaluate potential locations and utilized pairwise comparison to assign weights to each criterion. GIS-based spatial analysis was used to create factor and suitability maps for each criterion. Suitability was evaluated on a scale of 0 to 10 and each factor map was combined using the ArcGIS weighted overlay selection tool. The final map of the study represents the suitable site for a healthcare center in the Rajouri district and it shows the sites from the highly suitable to the least suitable area. In Rajouri district, mostly the central part can be considered very suitable as the population density of this area is higher compared to other areas of the district. The southwestern parts of the district are moderately suitable or least suitable sites for a new healthcare center. The study displays the pattern of the existing location of healthcare centers, mostly, the existing locations are not proper and suitable. Therefore, in the future, the allocation of healthcare centers must be in more adequate areas. Policymakers and healthcare professionals can be benefitted from this study in selecting suitable locations for future hospitals, which could ultimately improve access to healthcare services in the region. Additionally, the study can be contemplated in developing new policies for better transportation system in the study area.
-
A remote sensing and GIS-based analysis on the impact of dam construction towards the land use land cover pattern of Bakreswar Watershed, India
25-42Views:172The present study evaluates the impact of the dam construction on land use and land cover (LULC) pattern of the Bakreswar Watershed in the Birbhum District, West Bengal, India during 1990-2020. Landsat 5 TM and Landsat 8 OLI data were used to analyze the LULC pattern during the pre- and post-dam construction periods. Supervised image classification using the maximum likelihood algorithm was done to generate LULC and change detection maps in ArcGIS. LULC dynamic attitude and transfer matrix were prepared based on the LULC maps of four years. The results show that the dam construction significantly influenced the LULC pattern of the region. The highest rate of increase is seen in waterbody (86.37%) during 1990–2000 due to dam construction. Cultivated land also increased by 12.31% during this period. After the dam construction, the conversion rate from fallow land to cultivated land is higher in the downstream area rather than the upstream area. The area under barren land decreased by 53.28% in 1990–2000 and by 41.23% during 2009–2020 due to its conversion to built-up area. The built-up area rapidly increased during the past 20 years, by 34.57% and 45% during 1990–2000 and 2009-2020, respectively. Major change is seen along the Panagarh–Morgram Highway which connects two urban centers, Suri and Dubrajpur. Settlement concentration is also high around the Bakreswar Thermal Power Plant (BkTPP) and BkTPP Township. This study provides a useful approach to understanding the impacts of dam construction on cultivated area change and how transportation facility influences urban agglomeration.