Universal Journal of Geoscience 2(8): 229-241, 2014 http://www.hrpub.org DOI: 10.13189/ujg.2014.020801 Population Growth and Its Impact on Urban Expansion: A Case Study of Bahawalpur, Pakistan Asad Ali Khan * , Sana Arshad , Muhammad Mohsin Department of Geography, The Islamia University of Bahawalpur, Pakistan *Corresponding Author: asadkhaniub@yahoo.com Copyright © 2014Horizon Research Publishing All rights reserved. Abstract Land cover analysis and land use transformations, which are mainly associated with population growth, are considered as essential elements for studying the relationship between population growth, land use conversions and environmental consequences. Most cities of the world are becoming urbanized with every passing day and human induced land cover changes are modifying the pattern of land use in urban areas. Currently, Pakistan is standing at an influential place with regard to the size of its population, occupying sixth position among the world countries. Almost all its administrative entities have experienced unprecedented population growth throughout its entire life. Its urban areas are expanding more rapidly than their rural counterparts due to both by natural increase and by rural-urban migration. Study area for the current research, Bahawalpur is one of the fastest growing cities of Pakistan ranking twelfth among the cities of Punjab Province. This study aims at to examine the historical population growth of the city since last fifty years correlated with changing land use pattern and urban area expansion. Study is based on secondary data analysis using urban expansion indices for measuring the rate of urban change with increasing population growth. Application of regression model also verifies the increasing rate of urban area with population size and indicates an alarming situation for urban and city planners. Trend of urban growth in Bahawalpur shows that city is moving promptly towards highly urbanized cities of Pakistan. Its unprecedented and unplanned expansion may cause serious urban problems. Thus, it needs a serious look and attention of city planners. This study can also be helpful in providing some base line information. Keywords Population Growth, Urban Expansion Ratio, Land Use Pattern, Urban Change 1. Introduction Population growth is increase in number of (per hundred) people inhabiting in a given area over a given period of time whereas urbanization is a process of population concentration in a specific area. Urbanization usually proceeds in two ways; the multiplication of point of concentration and the increase in the size of individual concentration (Tisdale, 1941). Pham and Yamaguchi (2011)have defined the urbanization as “Changes in the territorial extent of an area due to developed transformation of land covers/ land uses from non-developed”. Urbanization can be discussed in two ways; the level of urbanization (existing situation of a region at any particular moment), and tempo of urbanization which refers to “trend of urban development” (UN, 1974). Increase in urban share of total population called “urbanization” is determined by three factors namely; natural growth, rural-urban migration, and reclassification of areas from rural to urban (Buhaug & Urdal, 2013).This process takes place due to the intensification of human activities including marketization and industrialization. It is expected that by the mid 20 th century every 3 rd person will be living in urban areas with faster demographic expansion and rural urban migration. More than three billion people will be residing in cities especially in Africa and Asia (Buhaug & Urdal, 2013; Pham, et al., 2011; UNHABITAT, 2010). Numerous studies support the evidence of rapid urbanization as a result of human induced land use/ land cover changes (Aljoufie, Zuidgeest, Brussel, & van Maarseveen, 2013; Briassoulis, 2000; Halder, 2013; H. Zhang, Qi, Ye, Cai, & Ma, 2013; Z. Zhang, Su, Xiao, Jiang, & Wu, 2013). It is a common observation that with growing population, urban areas are expanding. The rate of expansion, however, depends upon several other associated factors. It is understandable and several studies also argue that human population growth and resource consumption leads to the expansion of urban land area and bring changes in its land use and land cover (Cheng & Masser, 2003; Haregeweyn, Fikadub, Tsunekawa, & Tsubo, 2012; Tian et al., 2005). Land use is the varying activities performed by human beings to divide the landscape into different patterns with concerned changes (Carole L.Jolly & Barbara Boyle Torrey, 1993) and varies with human activities and the purpose for which land is being used. It can be used for food production, provision for shelter, recreation, processing of materials, and so on (Halder, 2013). Historical evidences demonstrate that