Land-use/cover change in Coimbatore urban area (Tamil Nadu, India)-a remote sensing and GIS-based study

摘要

The purpose of the present study was to explain land-use/cover changes in Coimbatore City Corporation using Landsat ETM+ and Landsat 8 Operational Land Imager (OLI) and Thermal Infrared Sensor (TIRS) data for the period of 2003-2014. Two Landsat images from years 2003 and 2014 were downloaded from USGS Earth Explorer. Maximum likelihood method was used to classify the images into five classes: urban fabric, vegetation, water bodies, agriculture lands, and barren lands. Overall kappa accuracy measure is about to 87.60 and 86.15% for the years 2003 and 2014, respectively. The change detection analysis has been performed for years 2003 and 2014 postclassified images. The results of the study have indicated that Coimbatore City has experienced rapid modifications in LULC, particularly in terms of urban/built-up area. Over the past 11 years, urban/built-up areas have increased by 94.5 km(2), resulting in a significant drop in the area of agricultural land and vegetation cover. It is found that (1) urban areas are increased 200% due to population growth cum rapid economic progress. (2) Vegetation cover decreased 38.76% due to conversion into urban features. (3) Water bodies in area increased to 15.78% due to eradication of encroachment. (4) There is loss of 1.89% of agricultural lands due to demand for construction activities. (5) About 85.24% of barren lands were converted into other uses, particularly 57.33% to urban areas. (6) Urban growth has accelerated towards north-eastern, northern, and eastern parts, where national highways exist. The built-up areas were dropped from 85.32 to 22.28%, within 5-km distance from the city center.