Introduction

Landscape changes are an important aspect as they play an important role in the global environment (Wood and Handley, 2001; Firmino, 1999) earth dynamics (Vitousek, 1994) and the spatial patterns of their transformation through time are undoubtedly related to changes in land uses (Potter and Lobley, 1996). Landscape changes are diverse but very often influenced by regional policies (Calvo-Iglesias et al., 2008). The  main  driving  factors  for global environmental changes are been  identified  as  urbanisation  (Phipps  et  al., 1986)  in  the  context  of  local  policies (Lipsky,  1992;  Meeus,  1993; Kubes,  1994). Urbanization being a global and highly irreversible process involving changes in vast expanse of land cover with the progressive concentration of human population. In order to address these urbanization challenges without compromising the environment values and their local sustainance, land use planning and necessary supporting data are crucial, especially to developing countries under severe environmental and demographic strains (Food and Agriculture Organization, 1995).

In India, there are 48 urban agglomerations which had urbanised to the maximum extent and are suffering under the deficit of basic amenities due to sprawling process. This has led to shifting of focus from the major urban agglomerations to tier II mega-polis, which are expected to handle the urban population. The basic infrastructure like roads, air and rail connectivity should be ensured. Apart from these, the government should also ensure adequate social infrastructure such as educational institutions, hospitals along with other facilities and the tier 2 towns must be planned to handle the growth of population over few decades, which otherwise leads to a phenomena Urban Sprawl.

Urban Sprawl is characterised by a sharp imbalance between urban spatial expansion and the underlying population growth (Bruekner, 2001). Sprawl  of  human  settlements,  both  around  existing  cities  and within  rural  areas,  is  a  major  driving  force  of  land  use  and  land  cover change  worldwide  (Batisani  &  Yarnal,  2009;  Gonzalez-Abraham et  al.,  2007). Sprawl is a process entails the growth of the urban area from the urban center towards the periphery of the city municipal jurisdiction. These small pockets in the outskirts will be lacking in basic amenities like supply of treated water, electricity, sanitation facilities. Understanding this kind of growth over past few decades is a very crucial factor that helps the administration to handle the population growth and helps to provide basic amenities and more importantly the sustainable management of local natural resources through regional planning.

The basic information about the current and historical land cover/land use plays a major role for urban planning and management (Zhang et al., 2002). Mapping landscapes on temporal scale provide an opportunity to  monitor  the  changes,  which  is  important  for  natural  resource  management  and sustainable  planning  activities. In this context, “Density Gradient” with the time series spatial data analysis is potentially useful in measuring urban development (Torrens and Alberti, 2000).

This study focuses on four tier II cities of Karnataka with objectives  to:  (1)  capture  the  extent  and location  of  land  use  change  in  four prime Tier II cities  in past 4 decades. (2)  Understand the urban growth pattern using density gradient and zonal approach, (3) understand the spatial pattern based on three landscape metrics. The results  could  be  used  in  decision  support  systems enabling  planner  to  get  a  first  idea  of  the  urban  development  trends.