Faculty Publications
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Item Study of dynamic changes through geoinformatics technique: A case study of Karwar coast, west coast of India(Springer, 2019) Yadav, A.; Dodamani, B.M.; Dwarakish, G.S.Shoreline is one of the geo-indicators of the coastal zone. Coastal zone is subjected to threats due to change in shoreline. Shoreline change leads to modification and causes for damages of properties, infrastructure around the shoreline region. These modifications, changes of land expands too many issues of the environment under the coastal zone. The present study was carried out by employing remote sensing and GIS techniques for the coastal regime of Karwar, India. LANDSAT-8 remote sensing data was integrated with the GPS data collected during the field survey. The satellite data is processed and analyzed using ERDAS IMAGINE 2014 tool and ArcGIS 10.3 tool, respectively. High Water Line (HWL) is considered for the extraction of shoreline. The visual interpretation of satellite imageries is carried out to distinguish the HWL. Net Shoreline Movement (NSM) was evaluated by adopting Digital Shoreline Analysis System (DSAS) tool. Statistical methods such as Weighted Linear Regression (WLR), Linear Regression Rate (LRR) and End Point Rate (EPR) were used to estimate the changes of shoreline. The present study reveals that shorelines of Karwar Coast, Ravindranath Taghore beach experiences an average erosion rate is −4.61 m/year (EPR), −1.49 m/year (LRR), and 0.19 (WLR) and Devbagh beach experiences an average erosion rate is −9.74 m/year (EPR), −7.53 m/year (LRR), and −11.55 m/year (WLR). © Springer Nature Singapore Pte Ltd. 2019.Item Comparative Analysis of Braiding Intensity of Kosi River Using Remote Sensing and GIS(Springer Science and Business Media Deutschland GmbH, 2025) Aman, A.L.; Dwarakish, G.S.The Kosi river is one of the major tributaries of river Ganga which is well known for change of its course. It originates from Tibet and after travelling through Himalaya and plains of Bihar, it joins river Ganga. The river carries huge sediment and, s accumulation of sediment causes formation of sand bars in the river. The downstream region of Birpur barrage is highly affected by this shifting tendency of the river. The satellite images of the river for year 1992, 2004 and 2016 were obtained to analyze the evolution in braiding of the river for two decades. The braiding intensity was measured by using the different braiding indices given by Brice, Rust and Sharma and compared in this study. The study area has been divided into four reaches and the braiding intensity for each of them were calculated. The braiding intensity by Brice varies from 2.38 to 4.93, from 1.06 to 1.75 as given by Rust and 2.45 to 6.5 by Sharma. The calculated braiding intensity indicates the overall decrease of braiding in the area. This study will be helpful to get an idea about the change in braiding intensity of the Kosi River in the downstream side of Birpur Barrage and about future changes. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2025.Item Use of geoinformatics and geophysical applications in landslide studies: An overview(World Research Association Vijay Nagar A.B. Road Indore 452 010, 2019) Thejashree, G.; Lokesh, K.N.; Dwarakish, G.S.Landslide is one of the hazardous geological phenomena which is gaining attention worldwide because of destruction caused by it. Due to the drastic increase in urbanization and human intervention in hilly regions, the destruction caused by mass wasting is increasing day by day. Landslides are far from the control of humans. But the destruction and losses caused by these calamites can be minimized, if their occurrence is known before time. This review paper aims at discussing how remote sensing, GIS and geophysical techniques can be utilized for investigation of landslides and mapping of landslide susceptible areas. Geophysical techniques can provide important information on physical characteristics linked with landslide mechanism. Complementarily, remote sensing and Geographical Information System (GIS) techniques play an important role in the generation of thematic layers related to landslide occurrences which aid to produce susceptible, hazard zonation and landslide inventory maps. Such integrated approach on landslides studies can bring about better understanding and help to take up mitigation measures to reduce the landslide hazards. © 2019, World Research Association. All rights reserved.Item Coastal vulnerability assessment of the future sea level rise in Udupi coastal zone of Karnataka state, west coast of India(2009) Dwarakish, G.S.; Vinay, S.A.; Natesan, U.; Asano, T.; Kakinuma, T.; Venkataramana, K.; Pai, B.J.; Babita, M.K.Udupi coast in Karnataka state, along the west coast of India, selected as a study area, is well known for sandy beaches, aquaculture ponds, lush greenery, temples and major and minor industries. It lies between 13°00?00?-13°45?00? north latitudes and 74°47?30?-74°30?00? east longitudes, the length of the coastline is 95 km, and is oriented along the NNW-SSE direction. It is vulnerable to accelerated sea level rise (SLR) due to its low topography and its high ecological and touristy value. The present study has been carried out with a view to calculate the coastal vulnerability index (CVI) to know the high and low vulnerable areas and area of inundation due to future SLR, and land loss due to coastal erosion. Both conventional and remotely sensed data were used and analysed through the modelling technique and by using ERDAS Imagine and geographical information system software. The rate of erosion was 0.6018 km2/yr during 2000-2006 and around 46 km of the total 95 km stretch is under critical erosion. Out of the 95 km stretch coastline, 59% is at very high risk, 7% high, 4% moderate and 30% in the low vulnerable category, due to SLR. Results of the inundation analysis indicate that 42.19 km2 and 372.08 km2 of the land area will be submerged by flooding at 1 m and 10 m inundation levels. The most severely affected sectors are expected to be the residential and recreational areas, agricultural land, and the natural ecosystem. As this coast is planned for future coastal developmental activities, measures such as building regulation, urban growth planning, development of an integrated coastal zone management, strict enforcement of the Coastal Regulation Zone (CRZ) Act 1991, monitoring of impacts and further research in this regard are recommended for the study area. © 2009 Elsevier Ltd. All rights reserved.Item Geomorphological behaviour of Sasihithlu, Mangalore coast, west coast of India(2011) Nagaraj, G.; Karjagi, A.; Kumar, M.; Dwarakish, G.S.Beach geomorphological studies have been carried out with help of conventional methods and remote sensing techniques. Conventional methods include beach profile surveys and beachwidth measurements whereas remote sensing techniques involved in utilization of satellite images, digitization and analyses. Beach profile surveys and beachwidth measurements are carried out at monthly intervals over a period of one year (September 2009 to September 2010) to understand dynamics of sediment along the coastal segment of 7km at Sasihithlu, north off Mangalore coastline. Six locations are selected based on their significant site characteristics along the coastal segment. It is observed erosion with steeper slopes during the monsoon and simultaneously deposition with flat and wider exposed slopes during the fair weather season. But the more drastic and dramatic changes are observed in the vicinity of Mulki-Pavanje rivermouth, since the rivers Mulky and Pavanje bring any kind of sediments irrespective of seasons. Because of this the profiles alter dramatically in the vicinity of rivermouth. It is estimated that the Sasihithlu beach has experienced a net loss of about 2515m 3/m, a net gain of about 3525m 3/m and hence a gain of about 1010m 3/m sediments in an annual cycle. Addition to conventional methods, remote sensing analysis is also carried out to detect the influence of rivers and their flow on rivermouth system in recent decades (1988-2009) with the help of satellite images and GIS tools. It is observed that the shifting tendency of rivermouth either south or north irrespective of seasons. However a detailed investigation on shoreline pattern showed a clear indication of shifting shoreline towards south. Therefore present study suggests to construct coastal protection structures on either side of the rivermouth, through that the damage to the property could be minimized. © 2011 CAFET-INNOVA TECHNICAL SOCIETY. All rights reserved.Item Hydrological effects of land use /land cover changes on stream flow at Gilgel Abay River Basin, Upper Blue Nile, Ethiopia(CAFET INNOVA Technical Society 1-2-18/103, Mohini Mansion, Gagan Mahal Road, Domalguda, Hyderabad 500029, 2016) Mulu, A.; Dwarakish, G.S.Water is the most important resource for the survival of living things and it is the most essential resource associated with land use/ land cover (LU/LC) changes. Therefore, it is very important to make evaluations of the expected impact on the hydrology and water resources due to expected changes. The main objective of this study is to assess the hydrological effect of land use/ land cover changes on stream flow at GilgelAbay river basin using Precipitation Runoff Modeling System (PRMS) model. System inputs are daily time-series values of precipitation, minimum and maximum air temperature, and parameter files which are generated from GIS Weasel. To identify effect of changes in LU/LC, vegetation type and vegetation density on stream flow, LU/LC, vegetation type and vegetation density data from 1990-2000 and 2001-2010 years were considered. This different period LU/LC, vegetation type and vegetation density with soil data and DEM were given to GIS Weasel to generate different parameters for PRMS model. These generated parameters together with time series data (daily minimum and maximum air temperature, daily precipitation and daily stream flow) feed to PRMS model to simulate stream flow for the years 1993-2000 and 2001-2008. From the time series data, climate changes (daily maximum and minimum temperature and daily precipitations) were kept the same as baseline period (1993-2000). The stream flow of 2001-2008 compared with baseline period (1993-2000) and the effect of LU/LC, vegetation type and vegetation density was identified using calibrated and simulated PRMS model. Hence, as LU/LC, vegetation type and vegetation density changed from 1993-2000 period to 2001-2010 period, stream flow increased from 7.8% (128.4 Mm3) to 25.3% (432 Mm3) and ET decreased from 4.2% (75 Mm3) to 20% (524 Mm3) from baseline period. For the whole simulation periods (2001-2008) stream flow increased by 10.9% (784 Mm3), but ET decreased 6.7% (43 Mm3) related to baseline periods. © 2016 CAFET-INNOVA TECHNICAL SOCIETY. All rights reserved.Item Prioritization of sub-watersheds for conservation measures based on soil loss rate in Tikur Wuha watershed, Ethiopia(Springer Science and Business Media Deutschland GmbH info@springer-sbm.com, 2020) Ketema, A.; Dwarakish, G.S.Soil erosion is unquestionably the trickiest land degradation that adversely agricultural productivity. Since resources are scarce, in developing countries like Ethiopia, implementing soil and water conservation practice at a time on the entire watershed is not feasible. Therefore, recognizing erosion-prone areas (the priority watersheds) based on the magnitude of soil loss rate is indispensable. The purpose of this study is to delineate priority sub-watersheds of the Tikur Wuha watershed in Ethiopia based upon the soil loss rate. A universal soil loss equation under the geographic information system environment was employed to estimate the soil loss rate. The result revealed that the average soil loss rate from the watershed is 14.13. It is resulting in a gross soil loss of 962,083 from the entire watershed. A small portion of the watershed (9.22%) is suffering from severe and very severe soil loss rate (> 25). A total of 14.41% of the watershed have soil loss rates above the maximum soil loss tolerance of the area (> 12). Among the seven sub-watersheds in the watershed, four sub-watersheds (SW_3, SW_1, SW_2, and SW_4) are falling under the top priority zone. Soil and water conservation measures should be executed rapidly in the Tikur Wuha watershed, consistent with the rank of the priority watersheds. © 2020, Saudi Society for Geosciences.