ABSTRACT

Urbanisation is a form of metropolitan growth fuelled by sets of economic, social, and political forces apart from the physical geography of an area. As population and activities increases in a city, the boundary of the city expands to accommodate the growth on the urban fringes, which is referred as sprawl. Sprawl generally infers to the regions with highly fragmented urban morphology impacting ecologically sensitive habitats. Cities in India have become a centre of urban agglomerations and have already attracted considerable attention because of their growth, population size, environmental influence and associated infrastructure, mobility issues. This is evident from the increase of mega urban centers (with more than 1 million inhabitants), which were four in 1990’s has increased to 48 cities (post 2010). There has been 2.1% increase in urban population during the last decade and the current share is about 27.8%. As per 2011 census there has been tremendous increase in the population and most of urban areas have reached the threshold. Tier II cities in India are also undergoing rapid changes in recent times which necessitates planned interventions to minimize the impacts of unplanned urbanization and consequent impacts on natural resources including basic amenities. This communication analyses the spatio-temporal patterns of urbanisation in the tier II twin cities of Karnataka state: Hubli and Dharwad.  The urbanization dynamics of the region with 5 km buffer from the city boundary has been studied considering the temporal remote sensing data of five decades.  Five km buffer has been chosen to account for possible urban sprawl regions. A gradient-oriented approach using multi-temporal remotely sensed data was adopted to systematically monitor the spatiotemporal dynamics of the twin cities. Land cover analysis shows that area under vegetation (cultivation and forests) has declined from 97% (1989) to 78% (2010) in Hubli and from 98% (1989) to 86% (2010) in Dharwad. Urban area has increased from 1.08 (1989) to 14.62 (2010)%.  Shannon entropy shows that Hubli-Dharwad is experiencing the tendency of sprawl in all directions. Spatial metrics reveal that the urban core of Hubli -Dharwad changed moderately over time and exhibited a spread out pattern of urban development with a moderate to low concentration of urban area towards the periphery. The new urban areas of developed rapidly along major transportation route connecting Hubli - Dharwad, resulting in urban development assuming an unusual outgrowth pattern.

Key Words— Land use, Land Cover, Remote Sensing, Image Classification, Spatial Metrics, Twin Cities, Tier II cities.