Study of decadal variations in width and mangrove cover of the Thane Creek, Maharashtra, India, using remote sensing

Abstract

The present study depicts decadal variations in the area, width and mangrove cover of Thane Creek, Mahara-shtra, India, using the remote sensing technique. The study is significant because the Creek has lush-green mangrove cover on its vast intertidal region and consi-derable urban developmental activities are occurring around it. Landsat datasets were used for different years from 1972 to 2014 and Sentinal 2A satellite data were used for the year 2020. To understand the variations in width from mouth to upstream, the Creek was divided into three zones, viz. mouth, middle and upstream. For mangrove cover estimation, supervized classification analysis was used for images from 2005 to 2014, while object-based image classification analysis with multi-spectral resolution was used for images from 2020. From the results, it can be confirmed that there is an overall increase in the spatial extent of mangroves and a reduc-tion in the width of Thane Creek. The study also shows that creek width had decreased by 1.15 km at the mouth and 0.08 km at the upstream end from 1972 to 2020, while mangrove cover had increased by 14.1 km2 from 2005 to 2020 (15 years). The overall reduction in the area between the west and east banks of the Creek was around 15.3 km2 from 1972 to 2020. This study shows that Thane Creek is rapidly narrowing at its northern end.