Assessing Dynamism of Urban Built-up Growth and Landuse Change Through Spatial Metrics: A Study on Siliguri and its Surroundings

Abstract

The process of rapid urban expansion in developing countries has been changing the landuse pattern in the cities and its outskirts, creating adverse effects on the harmony of environment and socio-economic structure on different spatial scale. Siliguri, the largest urban agglomeration in north Bengal, India, has been facing rapid urban growth since three decades that has resulted into continuous decrease of natural land and rapid peri-urban growth. This paper evaluates the landuse and landcover dynamics over three decades and has attempted to quantify the structure of built-up growth in rural-urban gradient. Multi-temporal satellite images were collected for landuse/landcover classification of 1990, 2001 and 2010. Landuse and landcover statistics with landscape metrics were analysed to calculate the impact of urban growth on land fragmentation process. The result shows that intensity of built-up growth is occurring in a rapid pace, whereas, the growth of other landuse classes are dynamic in nature. Agglomeration of built-up patches in the periphery of the city indicates the polycentric urban growth process. The built-up growth process in Siliguri experienced coalescence and infilling growth pattern near the existing patches and the vividness of coalescence is higher near the centre of the city. The present study concludes that spatial metrics is an aid to urban policy makers to understand the composition and configuration of urban landscape. It helps to determine whether the development can take place in a specific landscape and policy can reach a consensus.