Quantification of River Bank Erosion, Accretion and Its Effect on Land Use: A Case Study of the Ganges (Left Bank) Upstream of Farakka Barrage, Malda District, West Bengal

Abstract

Bank erosion is mainly a physical process of river dynamics that causes threat to the riparian and floodplain structures, engulfs fertile agricultural land, homes, means of livelihood and assets of the people. Along with physical causes, anthropogenic activities disturb the equilibrium of the river dynamics along the river stretch and accelerate the rate of bank erosion. The study focuses to quantify the decadal and mouza-wise erosion and accretion along the left bank of Ganges above Farakka barrage over the period of 1973 to 2017. An attempt has also been made to find regular erosion and accretion site and to quantify different engulfed land uses and emerged new char lands after 2011 along the Gangetic tract of three affected CD blocks. The entire study is analysed through geo-spatial environment using multi-temporal Landsat imageries and land use map of three blocks. NDWI is used for demarcating river banklines and ‘Zonal Statistics as table’, a tool of ArcMap 10.1, has been used for mouza-wise water coverage area. The study reveals that large amount of lands are eroded along the left bank of the Ganges and Manikchak block has the maximum mouzas which were engulfed among the three victimised blocks. Bank erosion was maximum just after the construction of Farakka barrage. Regular erosion and accretion zones are also identified. Maximum loss of vegetables farm land, agricultural land (multi-crop) and human habitats was found in Manikchak block. It is also found that, eroded land had been compensated by the emerged new mid-channel bars (chars) on river bed within the administrative boundary of three blocks.

Keywords: Bank erosion, accretion, land use change, GIS analysis

Cite this Article

Guchhait S. Quantification of River Bank Erosion, Accretion and its Effect on Land Use: A Case Study of the Ganges (Left Bank) Upstream of Farakka Barrage, Malda District, West Bengal. Journal of Remote Sensing & GIS. 2018; 9(1): 34–48p.