URBAN SPRAWL ANALYSIS USING SHANNON’S ENTROPY AND FRACTAL ANALYSIS: A CASE STUDY ON TIRUCHIRAPPALLI CITY, INDIA

Abstract

Urban sprawl places a major role in urban growth management all over the world. Urban growth of the city is analysed for the effective planning and improving the socio-economic conditions for decision making and the development of the city. In this study, the urban sprawl of Tiruchirappalli city is analysed from 2006 to 2017 using data of Indian remote sensing satellites, Resourcesat-1 and Resourcesat-2 with multi spectral band (red, green and near-infrared). The temporal change for four-time periods is calculated using object based image analysis temporal inversion approach. From 2006 to 2017 there is an increase in total urban area from 58 km2 to 90 km2, resulting of 33% increment in 11 years. Shannon entropy is calculated for four-time periods and it shows that after 8 km from Central Business District (CBD), Shannon entropy is increasing and dispersion is high. The influence of roads on urban sprawl is calculated using buffer function analysis and the highest contribution among all the highways is by NH-67 and NH-210.The fractal analysis of the urban area for four-time period is performed and fractal dimension is calculated. Fractal dimension helps in measuring the space filling extent and urban growth complexity and is used to characterise the compactness of urban pattern and regularities of urban boundaries.The fractal dimension of Tiruchirappalli increases from 1.584 in 2006 to 1.639 in 2017.