INTRODUCTION
Human induced land use and land cover (LULC) changes have been the major drivers for the changes in local and global environments. Land cover dynamics involving conversion of natural resources (vegetation, water bodies, green spaces) into urban space have affected various natural and ecological process . Urbanisation is a dynamic complex phenomenon involving large scale changes in the land uses at local levels. Analyses of changes in land uses in urban environments provide a historical perspective of land use and give an opportunity to assess the spatial patterns, correlation, trends, rate and impacts of the change, which would help in better regional planning and good governance of the region (Ramachandra, et al., 2012). Urban growth is a spatial and demographic process, involving concentration of human population to the land area which has high economy (Bhatta, et al., 2010a; Luck & Wu, 2002; Ramachandra et al., 2012).
Urban growth pattern, have a direct influence on urban development process, which extends its influence on the neighborhood (Bhatta, 2009; Nelson, 2010), leading to Urban sprawl, which is often referred as peri-urban growth. Urban sprawl refers to a small clusters of medium to low-density urban growth in the outskirts without proper basic amenities (Bhatta et al., 2010b; Ramachandra et al., 2012; Petrov et al., 2009; Sudhira et al., 2004). This form of peri urban low density growth apart from lacking basic amenities also have a number of social, economic and environmental disadvantages (Bhatta et al., 2010b; Ramachandra et al., 2012).
A quantitative and qualitative analysis of the landscape structure is essential to analyse of the patterns of landuse change. Thematic land-use and land-cover maps generated allow us to quantify characteristics such landscape heterogeneity (Baldwin etal., 2004) and landscape fragmentation (Benedek et al., 2011; Gao& Li, 2011; Sudhira et al., 2004). Spatio-temporal data (Remote Sensing (RS) data) with Geographic Information System (GIS) are helpful in data acquisition and analysis of LULC changes and for qualitative and quantitative results to understand the changes (Ramachandra et al., 2012; Sudhira et al., 2003). Temporal RS data has been used to analyze and understand the changes and impacts of human activities on the natural ecosystem (Yang et al., 2003; Herold et al., 2005; Cowen and Jensen, 1998; Xu et al., 2005; Berberoglu and Akin, 2009). Urban growth is captured based on spatial configuration and its dynamics (Muller et al., 2010; Seto&Fragkias, 2005; Xian & Crane, 2005; Sudhira et al., 2003). Spatial metrics have been used for describing landscape structure (McGarigal, 2002; McGarigal et al., 2002; Sudhira et al., 2004; Ramachandra et al., 2012) and for a wide range of applications, including the assessments of land-use change (Iverson, 1988 ; Turner &Ruscher, 1988; Ramchandra et al., 2012 ), required for landscape planning and management (BotequilhaLeitão& Ahern, 2002), detection of changes in vegetation patterns (Fernandez, Aguiar& Ferreira, 2011; Kelly et al., 2011), changes in landscape structure (Pocas et al., 2011; Ramachandra et al., 2012, Bharath et al., 2012 ), for assessing the impacts of urbanization on the landscape ( Gao& Li, 2011; Li et al., 2010; Ramachandra et al., 2012; Sudhira, 2004, Bharath et al., 2012). Common spatial metrics have been computed for describing the structural characteristics and growth patterns of the built-up area. Herold et al., (2003), for instance, used spatial metrics to characterize urban growth patterns in four administrative regions of Santa Barbara. Calculation of the metrics for each region was based on a visually interpreted land-use map representing the landscape as patches of a built and non-built class. Ramachandra et al.(2012) and Bharath et al., (2012) have examined land-use changes encompassing the urban area and peri urban area using spatial metrics at the class level. This work adopted gradient and direction analysis to locate and understand the local dynamics of changes in urban pattern. Further using Concentric buffer zones (Seto&Fragkias, 2005, Settur et al., 2012) , transects or rectangular sample plots (Weng, 2007, Luck & Wu, 2002) were also used for the sprawl analysis. Spatial metrics have been proved as a valuable tool in comparing urban form and land-use dynamics (Huang et al., 2007; Schwarz, 2010). The review illustrates thatsignificant research contributions ranging from gradient analyses to geospatial tool applications have been made to understandthe urban growth pattern, quantification of complex patterns or processes of urban growth (Dietzel et al., 2005; Herold et al., 2003; Peng et al., 2010; Ramachandra et al., 2012).
Human induced land use and land cover (LULC) changes have been the major drivers for the changes in local and global environments. Land cover dynamics involving conversion of natural resources (vegetation, water bodies, green spaces) into urban space have affected various natural and ecological process . Urbanisation is a dynamic complex phenomenon involving large scale changes in the land uses at local levels. Analyses of changes in land uses in urban environments provide a historical perspective of land use and give an opportunity to assess the spatial patterns, correlation, trends, rate and impacts of the change, which would help in better regional planning and good governance of the region (Ramachandra, et al., 2012). Urban growth is a spatial and demographic process, involving concentration of human population to the land area which has high economy (Bhatta, et al., 2010a; Luck & Wu, 2002; Ramachandra et al., 2012).
Urban growth pattern, have a direct influence on urban development process, which extends its influence on the neighborhood (Bhatta, 2009; Nelson, 2010), leading to Urban sprawl, which is often referred as peri-urban growth. Urban sprawl refers to a small clusters of medium to low-density urban growth in the outskirts without proper basic amenities (Bhatta et al., 2010b; Ramachandra et al., 2012; Petrov et al., 2009; Sudhira et al., 2004). This form of peri urban low density growth apart from lacking basic amenities also have a number of social, economic and environmental disadvantages (Bhatta et al., 2010b; Ramachandra et al., 2012).
A quantitative and qualitative analysis of the landscape structure is essential to analyse of the patterns of landuse change. Thematic land-use and land-cover maps generated allow us to quantify characteristics such landscape heterogeneity (Baldwin etal., 2004) and landscape fragmentation (Benedek et al., 2011; Gao& Li, 2011; Sudhira et al., 2004). Spatio-temporal data (Remote Sensing (RS) data) with Geographic Information System (GIS) are helpful in data acquisition and analysis of LULC changes and for qualitative and quantitative results to understand the changes (Ramachandra et al., 2012; Sudhira et al., 2003). Temporal RS data has been used to analyze and understand the changes and impacts of human activities on the natural ecosystem (Yang et al., 2003; Herold et al., 2005; Cowen and Jensen, 1998; Xu et al., 2005; Berberoglu and Akin, 2009). Urban growth is captured based on spatial configuration and its dynamics (Muller et al., 2010; Seto&Fragkias, 2005; Xian & Crane, 2005; Sudhira et al., 2003). Spatial metrics have been used for describing landscape structure (McGarigal, 2002; McGarigal et al., 2002; Sudhira et al., 2004; Ramachandra et al., 2012) and for a wide range of applications, including the assessments of land-use change (Iverson, 1988 ; Turner &Ruscher, 1988; Ramchandra et al., 2012 ), required for landscape planning and management (BotequilhaLeitão& Ahern, 2002), detection of changes in vegetation patterns (Fernandez, Aguiar& Ferreira, 2011; Kelly et al., 2011), changes in landscape structure (Pocas et al., 2011; Ramachandra et al., 2012, Bharath et al., 2012 ), for assessing the impacts of urbanization on the landscape ( Gao& Li, 2011; Li et al., 2010; Ramachandra et al., 2012; Sudhira, 2004, Bharath et al., 2012). Common spatial metrics have been computed for describing the structural characteristics and growth patterns of the built-up area. Herold et al., (2003), for instance, used spatial metrics to characterize urban growth patterns in four administrative regions of Santa Barbara. Calculation of the metrics for each region was based on a visually interpreted land-use map representing the landscape as patches of a built and non-built class. Ramachandra et al.(2012) and Bharath et al., (2012) have examined land-use changes encompassing the urban area and peri urban area using spatial metrics at the class level. This work adopted gradient and direction analysis to locate and understand the local dynamics of changes in urban pattern. Further using Concentric buffer zones (Seto&Fragkias, 2005, Settur et al., 2012) , transects or rectangular sample plots (Weng, 2007, Luck & Wu, 2002) were also used for the sprawl analysis. Spatial metrics have been proved as a valuable tool in comparing urban form and land-use dynamics (Huang et al., 2007; Schwarz, 2010). The review illustrates thatsignificant research contributions ranging from gradient analyses to geospatial tool applications have been made to understandthe urban growth pattern, quantification of complex patterns or processes of urban growth (Dietzel et al., 2005; Herold et al., 2003; Peng et al., 2010; Ramachandra et al., 2012).
This communication analysesthe growth pattern of a developing city in Karnataka State, India. The region has large neighborhood of various classes with diverse landscape patterns. The objectives of the study are (a) to understand the land cover and land use dynamics using temporal remote sensing data, b) quantify urban growth , (b) to understand the urban growth patterns in different locations using gradients and (d) to assess the pattern of growth over past two decades using spatial metrics over gradient.
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