Land use land cover mapping and monitoring urban growth using remote sensing and GIS techniques in Mangaluru, India

Urbanisation induced land use and a land cover change is a proliferating phenomenon worldwide. The impacts of chaotic urban growth are all well documented. To overcome the ill effects of urbanisation, continuous monitoring and sustainable planning are the keys. As the future urban growth in India is predicted to take place in small cities of less than a million populations, it is the crucial time to plan a strategy for sustainable urban growth. Mangaluru, being a small, emerging city has the basic fertility required for urban growth. But the deficiencies of spatial data availability and lack of insight for impending urbanisation scenario would hamper the sustainable management of urban growth in the region. In this context, the current study proposes to map land use and land cover and monitor the spatiotemporal dynamics of urban growth in Mangaluru urban agglomeration, India, during 1972-2018. The present study employs techniques of remote sensing and geographic information system (GIS) and uses Landsat series of imageries. The land use and land cover changes and dynamics of urban growth have been studied using change detection, Shannon entropy, and spatial trend analysis. The study reveals that the rapid increase in the built-up area is largely induced by intense in fill growth in the core range of the city which is further corroborated by the Shannon entropy value, which indicates the compact nature of city growth. It has been found that built-up area has increased from 3.68% in 1972 to 18.79% in 2018. Agricultural land on the other hand decreased from 36.51-11.22% during 1972-2018 period. The spatial trend of change analysis represents the expansion of built-up land along with the transport network, and predominantly following a north-south course. Landsat image classification has also shown that Land use and land cover have largely changed during 1972-2018.