Conclusion

Urban dynamics research provides vital clues for evolving appropriate land use policy for sustainable management of natural resources. In this paper, an attempt is made to quantify and qualitatively describe the patterns of urban growth. Measures of capturing the pattern of growth using entropy, density, clumpiness, and shape will help in the better city planning and facilitate basic amenities and infrastructure. The urban built-up area in the study region (Ahmedabad City with buffer) has increased by more than five times from 1975 to 2010. The fastest growing period was 2000-2010, when urban built-up area increased its spatial extent by 163%. The spatial expansion did not take place equally in all directions. The outward sprawl in the SW and NE directions is higher compared to other zones. Shannon’s entropy and spatial metrics helped in understanding the form of urban sprawl and its spatial pattern. Increased values of entropy show the tendency of sprawl in all directions. Urban sprawl is taking place continuously at a faster rate in outskirts and buffer regions. Spatial metrics have been found to be effective in determination of urban sprawl and its spatial distribution. The pattern of growth has drastically altered the shape of the city that has evolved from simple shaped growth at the core to fragmented complex growth at outskirts. Spatial metrics analysis through gradients helped in understanding the relationship of sprawl with causative factors. This approach is useful for the regional planners and authorities to understand and determine spatial patterns of urbanisation. PCA helped in prioritizing spatial metrics for better elucidation. Results show that the core or the city administrative region (until gradient 7) with a clumped patch forms single dominant land use and little scope for further urbanisation. City outskirts as well as the buffer region are experiencing dispersed growth or sprawl. Temporal remote sensing data and gradient based spatial metrics analyses were useful in understanding the dynamic phenomenon of rapidly urbanizing landscape.