Journal Articles
Permanent URI for this collectionhttps://idr.nitk.ac.in/handle/123456789/19884
Browse
2 results
Search Results
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 Studies on the dynamic response of coastal sediments due to natural and manmade activities for the Puducherry coast(National Institute of Science Communication and Policy Research, 2014) Vijayakumar, G.; C, C.; Sundararajan, T.; Govindarajalu, D.This paper presents the response of the coastal sediments by the impact of waves and construction of manmade structures in the Puducherry coastal stretch, East coast of India. Based on the real time wave climate data which was collected from the nearshore region of coast using wave rider buoy and wave direction indicator. The quantum of sediment movement is calculated using CERC formula for three years (2007, 2008, and 2009) and compared with Kamphuis method for one year i.e., 2009. In order to achieve a more reliable value on the sediment movement a sand trap was used at the littoral zone to collect the actual sediment samples for a period of two months i.e., February and March 2009. For all the three observation period the predominant sediment transport rate is Northerly. Estimated sediment transport rates were also determined by Kamphuis method. From the results obtained, CERC formula ‘over predicts’ the sediment transport rate when compared with Kamphuis method. The actual sediment transport calculated using sand trap was found to be 60% reliable when compared with theoretical sediment transport rate which has been determined by using Kamphuis method. © 2014, National Institute of Science Communication and Information Resources (NISCAIR). All rights reserved.