Spatio-temporal landuse/landcover (LULC) change analysis of Kolong River basin, Assam, India using Geospatial technologies

摘要

The Kolong River of Nagaon district in Assam, which once used to be a prize possession for the people of the state in general and for the people of Nagaon in particular, is presently gasping on its death-bed because of a ruthless and untenable act perpetrated on it in the name of engineering solution to the increasing flood hazard attributed to it in the aftermath of the great Assam earthquake of 1950. In the backdrop of the above scenario, it is high time we undertake a holistic river restoration programme for the Kolong River based on state-of-the art knowledge and scientific know-how currently available on the subject. Application of remote sensing and GIS, techniques will serve as a basic set of mapping tools for creation of a baseline overview of the river basin. Attempt has been made in this study to map out the status of land use/land cover of Kolong basin with a view to detect changes that had occurred in their status particularly in the built-up area and agricultural land. The landuse/ landcover of the study area have been categorized into six broad classes based on the variation observed in the area. The results showed a significant negative change in total agricultural land with a total decrease from 2216.96 Km2 to 1449.39 Km2 during the year 1967-68 to 2014; while an overall positive change was observed in case of built-up area which has increased from 1069.05 Km2 to 1838.84 Km2 during the study period. Single layer overlay analysis was also performed in order to verify the overall change under each landuse/landcover class. Significant reduction (704.97Km2) in agricultural land to built-up area was verified by the conversion matrix.