Developing Plot Level Database on Land Accretion: A Case Study on Sandwip Island of Bangladesh

Erosion and accretion are continuously changing the shape, size and configuration of Sandwip Island of Bangladesh. Plot level database are very significant in order to document these changes from micro levels. For this purpose, an attempt has been made to develop plot level database about land accretion of the Island since 1913 through overlapping Mauza maps using GIS (Geographic Information System) data. Here a case study named Thak Kuchiamora mauza, experiencing alluvion located in the eastern side of the Sandwip Island has been presented from micro level. Both primary and secondary data have been used for this study. CS (Cadastral Survey) and RS (Revisional Settlement) mauza maps available from DLRS (Directorate of land records and Surveys) office has been collected and overlaid on satellite images (2016) so that the accretion context and circumstances can be detected. Plot level information has been extracted from collected mauza maps and integrating with present land cover features changing scenario has been analysed. During cadastral survey 172 plots have been recorded and in the Revisional settlement operation it increased into 502 plots due to land fragmentation. From 1970 to 2000 period the area accreted about 220 m from southwest to northeast direction. Analyzing accreted database over different period it has been concluded that from Revisional settlement operation (1970) to 2016 it has been recorded that the mauza has increased about 1185 m from west to east. The newly formed landmass of the area hasn’t stable enough for permanent land use yet.