Understanding the Spatial Patterns of Green Spaces for 2000-2016 in the City of Ahmedabad

Urban Green Spaces (UGS) has numerous amenity values for recreation, socialization, environment, leisure, aesthetic, etc. well documented in many research studies to enhance and maintain the urban quality of life. Most studies focus on evaluating the functional benefits of green spaces or on other aspects of it like conservation and preservation. However, little is been known about the dynamics of spatial change of green spaces in terms of their geometry, landscape and arrangements. This paper studies the temporal as well as spatial change of green spaces in comparison to other classes like agriculture, vacant land, built up, water body and roads. Ahmedabad city has been chosen for this empirical study over the period of 2000 to 2016 due to high level of infiltration of people over the last decade along with maintaining its high urban green spaces compared to other growing cities of India. The study takes help of remote sensing Landsat USGS image data and GIS derived landscape metrics for its spatial analysis. Percentage changes in different classes of urban land cover especially vegetation were calculated for Ahmedabad city and each of the thirty seven common wards eliminating the six wards of old city for the year 2000 and 2016. The changes in landscape metrics, viz, class area, no. of patches, patch density, mean patch size, patch size standard deviation, edge density, mean shape index, area weighted mean shape index and largest patch index for Ahmedabad city as well common wards were calculated. These landscape metrics are only limited to shape and size measures of geometry for class of vegetation in this study. It revealed vegetation area is increased by 3% towards the periphery and decreased by 4% in the core of the city whereas total built up increased by 18.4%. Further, increase in vegetation shows increase in number of green patches, edge density, shape regularity, largest patch index and mean patch size except the few wards. It reveals contrasting pattern of sparse and conglomerated distribution of vegetation and its form of conversion. These patterns evolved over a period of 16 years helps to understand the spatial and physical behaviour of green spaces and other classes. Understanding such patterns deeply can assist for better urban planning monitoring, strategies and decisions. It should provide insights and aid in government policies for urban planning and conservation. The simulation of GIS applications in the study helps for analytical thinking and spatial tool-based planning.