Assessment of river channel dynamics and its impact on land use/land cover in the middle Ganga plain, India.

Channel dynamics is one of the important features of the Ganga River. It has become a major concern for floodplain residents as well as for policymakers interested in riverine planning and management. The present study used remote sensing datasets for a period of about 46 years (1972 to 2018) and explored the spatial and temporal migration of the Ganga River channel in the middle Ganga plain (MGP), India. The raster datasets were obtained from the United States Geological Survey (USGS) Earth Explorer. Various features were extracted manually, and supervised classification was performed for land use and land cover (LU/LC) analysis. This study also used conversion maps to outline the changes within and among different LU/LC classes. The results show that a significant portion of land along both banks of the Ganga River has changed from 1972 to 2018. This research pinpoints five main sites indicating active channel migration: (i) MS1, (ii) MS2, (iii) MS3, (iv) MS4, and (v) MS5. All these five sites highlight a significant increase in the built-up area and vegetation cover. Fallow land and waterbodies have declined at all these five sites. MS1 was the most affected site by the migration of the Ganga River channel. The results indicate that channel migration and improvements in geomorphic units considerably affect LU/LC. [ABSTRACT FROM AUTHOR]