Research Publications

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    Assessment of coringa mangrove shoreline migration using geospatial techniques
    (Journal of Operational Oceanography, 2020-11-06) Sharma, Garima.; Patnaik, K. V. K. R. K.
    Coringa Mangroves in the Kakinada Bay have evolved as the second-largest mangroves in the East Coast of India over the last century. The Coringa Mangrove shoreline has accreted considerably in the past decades as observed from the satellite imageries, adding value to the natural biodiversity of flora and fauna. This study is focused on quantifying the long term changes of Coringa mangrove shoreline using the Landsat imageries for years 1977, 1988, 2000, and 2013 using the Digital Shoreline Analysis System. For a mangrove shoreline length of 20.5 km, 41 transects were cast at an interval of 500 m for calculating the change and their migration distance using three statistical methods, namely End Point Rate (EPR), Net Shoreline Movement (NSM) and Linear Regression Rate (LRR). Results showed that there was considerable growth of mangroves in the bay leading to the seaward migration of the mangrove shoreline from the year 1977– 2013. The study observed the difference in the mangrove shoreline migration dynamics in the South-eastern (near the bottom of the spit) and the western part of the Kakinada Bay. The calculated average degradation rate due to erosion is −5.19 m.yr−1 and the average accretion rate leading to their growth is 14.83 m.yr−1 for all transects of the 20.5 km mangrove shoreline stretch during this period. The results hold importance as they help in identifying the regions prone to mangrove degradation and enable management planning for the protection of the eroding stretch of the mangrove shoreline.
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    Assessment of Coringa Mangrove shoreline migration using geospatial techniques
    (Taylor and Francis, 2022-05-04) Sharma, G.; Patnaik, K. V. K. R. K.
    Coringa Mangroves in the Kakinada Bay have evolved as the second-largest mangroves in the East Coast of India over the last century. The Coringa Mangrove shoreline has accreted considerably in the past decades as observed from the satellite imageries, adding value to the natural biodiversity of flora and fauna. This study is focused on quantifying the long term changes of Coringa mangrove shoreline using the Landsat imageries for years 1977, 1988, 2000, and 2013 using the Digital Shoreline Analysis System. For a mangrove shoreline length of 20.5 km, 41 transects were cast at an interval of 500 m for calculating the change and their migration distance using three statistical methods, namely End Point Rate (EPR), Net Shoreline Movement (NSM) and Linear Regression Rate (LRR). Results showed that there was considerable growth of mangroves in the bay leading to the seaward migration of the mangrove shoreline from the year 1977–2013. The study observed the difference in the mangrove shoreline migration dynamics in the South-eastern (near the bottom of the spit) and the western part of the Kakinada Bay. The calculated average degradation rate due to erosion is −5.19 m.yr−1 and the average accretion rate leading to their growth is 14.83 m.yr−1 for all transects of the 20.5 km mangrove shoreline stretch during this period. The results hold importance as they help in identifying the regions prone to mangrove degradation and enable management planning for the protection of the eroding stretch of the mangrove shoreline.
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    Quantification of changes in seabed topography with special reference to Hansthal Creek, Gulf of Kachchh, India.
    (Journal of costal research, 1993-01) Pattanshetti, S.S.; Chauhan, Onkar.; Sivakholundu, K. M.
    Variations in the bathymetry in macrotidal Hansthal Creek between 1984 and 1950 along 14 closely spaced lines, are used to quantify the volumetric changes in seabed topography in terms of erosion/accretion. Two surfaces from the bathymetric data of 1984 and 1950 have been modelled. The profile wise comparison along the transects indicates a dynamic deformation due to distinct alteration in the shoreline and a shift in the channel course. The shoreline has retreated 650 and 450 m on the northern and southern banks respectively. The studies suggest scouring of horizontally deposited fine sediments (clays deposited in an antecedent depositional phase) in the Hansthal Creek due to existing dynamic equilibrium among (a) influence of physiography in amplifying the tidal range, (b) increased efflux due to contribution through inter-creek water movements, and (c) high magnitude currents. Magnitude of erosion in the creeks, particularly on the flanks, is much more than in the axial channel. The degree of the erosion reduces from the Hansthal Creek mouth to inland (area in the close vicinity of Little Gulf of Kachchh). During the last 34 years about 71.5 x 10 super(6) m super(3) from this creek during the course of the present study. Offshoreward movement of scoured sediments and their redeposition in the outer gulf as a fill in the paleo-channel is observed.