Land Use / Landcover Mapping and Sustainability Analysis of Chennai City, Tamilnadu, India
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International Journal of Civil Engineering and Technology (IJCIET) Volume 9, Issue 13, December 2018, pp. 1201–1210, Article ID: IJCIET_09_13_123 Available online at http://iaeme.com/Home/issue/IJCIET?Volume=9&Issue=13 ISSN Print: 0976-6308 and ISSN Online: 0976-6316 ©IAEME Publication Scopus Indexed LAND USE / LANDCOVER MAPPING AND SUSTAINABILITY ANALYSIS OF CHENNAI CITY, TAMILNADU, INDIA N. Vaani Assistant Professor (Sr.), Centre for Disaster Mitigation and Management (CDMM), VIT, Vellore, Tamil Nadu, India Aditya Anand Student, B.Tech- Civil Engineering, School of Civil and Chemical Engineering (SCALE), VIT, Vellore, Tamil Nadu, India. ABSTRACT With the growing trend of population and migration of people from rural to urban area, the cities of nation are becoming overcrowded. To manage the needs of people and also to safeguard the resources available, the planners and policy makers need to have a current landuse map of any city or town. The present study focuses on the preparation of landuse map of Chennai, the capital city of Tamilnadu. As the growth of the city is fast and uncontrollable, it would be well prudent if the landuse map of present-day city has been prepared. Though there are wide sources like Global Landcover Facility (GLCF) are available to get free satellite images and many studies have been carried out by preparation of landuse/landcover map from them, the attempt has been made to prepare landuse map from the very prominent web map service render by Google Earth images. The extraction of image tiles from Google Earth is made possible using an open source software named Elshayal Smart. The whole Chennai city could be covered using 735 individual tiles of Google earth images. After mosaicking and clipping the required city bound, onscreen digitization of various landuses/landcovers was done using ArcGIS software. The establishment of topology and hence the area of various classes were then obtained. The area occupied by built-up area is 126.58 sq.km, which is the highest as compared to other landcover classes like agricultural area (16.44 sq.km), open land (12.80 sq.km) and water bodies (07.19 sq.km). The results of landuse/landcover analysis of various zones of Chennai city would facilitate the city planners to maintain sustainable growth. Key words: Land use/ Land cover mapping, Sustainable growth, Geographic Information Systems (GIS), Elshayal Smart, Google Earth images Cite this Article: N. Vaani, Aditya Anand, Land Use / Landcover Mapping and Sustainability Analysis of Chennai City, Tamilnadu, India, International Journal of Civil Engineering and Technology (IJCIET) 9(13), 2018, pp. 1201–1210. http://iaeme.com/Home/issue/IJCIET?Volume=9&Issue=13 http://iaeme.com/Home/journal/IJCIET 1201 [email protected] Land Use / Landcover Mapping and Sustainability Analysis of Chennai City, Tamilnadu, India 1. INTRODUCTION As given by Rio declaration, people of any country are eligible to lead a healthy and productive life in harmony with nature [1]. But, due to fast urbanization in many of the metropolitan cities of the world, the sustained lifestyle of people is getting badly affected. The scarcity of land and water and hence the shortage of food production and drinking water are the major concern due to unplanned growth of a city. The forecast for four decadal period from 2010 to 2050 says that the urban population will rise by 80 percent i.e., from 3.5 billion in 2010 to 6.3 billion in 2050 [2]. This two-fold increase within the short period will have great impact on the future demand for food and water. In this worsening condition, where more people are moving to cities for better job opportunities, it is the responsibility of urban planners to make smart decisions by smart planning for the growth of city. Fifty percentage of the total population in Tamilnadu are living in major cities of the state, which is next highest to Maharashtra and Gujarat in India [3]. Any further prolongation of this scenario will cause reduction in agricultural land, congested habitats, deforestation, issues in distribution of water and traffic irregularities, sewage treatment problems, air and noise pollution etc. To manage the city growth and to maintain the sanity of the city, the effective tool that the planners can rely on is accurate and recent urban landuse information for carrying out various activities in urban planning and management. The landuse map is proved to be an efficient tool in preparation of master plan, distribution of the basic amenities, proposal of any urban infrastructure and planning of smart cities. The other research areas involving landuse mapping are study of changes that have occurred in the landuse over the past years, urban sprawl pattern analysis, prediction of future landuse, changes etc. In recent years, the conventional use of field survey methods is obsolete and the effective use of satellite data for the preparation of urban landuse maps are in practice. The advancement in geospatial industry and the satellite data availability enable the process in a much appreciable way. There are plenty of studies in which the landuse mapping from the muti temporal satellite images using image classification techniques has been done [4,5]. The satellite images can now be downloaded from varied web data sources like the most familiar one of global landcover facility (GLCF). This present study uses the images downloaded from Google Earth using the software named Elshayal Smart, which is freely available. While other data services compromise either on the resolution or on the latest data availability, Google Earth surprisingly gives both at its best. The data security concern of few places could also be overcome as Google Earth brings even some wacky places into light. The most beautiful and amazing landscape view at very good resolution makes the choice of data source as perfect. The present study area is Chennai, the capital city of Tamilnadu, India. In 2011, according to census of India, Chennai city was ranked as the fifth-largest city and fourth populous urban agglomeration in India. The urban area of Chennai has increased from 1.46 to 18.55% in two decades (1991 – 2012), the vegetation cover has reduced by 22% during this period. [6,8] The fast growth of the city in an unplanned manner has its impact on the social, political, economic and ecological landscapes of cities. India’s urban population has increased by 91 million between 2001 and 2011 [7]. The intense development of Chennai city in the outskirts results in surrounding peri urban areas which lack basic amenities [8]. http://iaeme.com/Home/journal/IJCIET 1202 [email protected] N. Vaani, Aditya Anand Figure 1 Map showing the study area Landuse map preparation for such a very fast-growing city would be a key tool to bring sustainability. The taluk wise analysis gives the planners a clear idea to help future growth of the city. Since Chennai in Tamilnadu is one of the 109 cities selected for the recent smart city project [9], the implementation of the same can be made efficiently using the prepared land use map of the city. 2. DATA COLLECTION AND EXTRACTION The complete image of the study area in the year 2017 was extracted from Google Earth, a virtual mapping environment where the earth's surface features are mapped by overlaying various satellite images, aerial photographs using geographic information system (GIS). The perpendicular or oblique view of all earth surface features and buildings can be obtained using Google Earth. The images of Google Earth have varied resolution. Two dimensional images are mostly seen for many places. Three dimensional images are also available for few places. But, using Digital Elevation Model (DEM), 3D view of entire earth is made possible. Elshayal Smart, an open source GIS software developed by a team of GIS programmers from Africa, Arab and Egypt was used to extract georeferenced images from Google Earth. The tiles of georeferenced images in a desired zoom level from Google Earth have been downloaded using the Elshayal Smart software. The software enables selection of the adjacent tiles for extraction depending on the user requirement as either top or bottom, left or right of previous extracted image tile. As the extracted images are having coordinate information, the further processing and analysis of the data is also made easy. http://iaeme.com/Home/journal/IJCIET 1203 [email protected] Land Use / Landcover Mapping and Sustainability Analysis of Chennai City, Tamilnadu, India Figure 2 A sample single image tile of study area extracted from Google Earth using Elshayal Smart. 3. IMAGE MOSAICKING AND GIS ANALYSIS The entire study area is covered by total of 735 image tiles. Those image tiles were extracted from Google Earth using Elshayal Smart. All the individual images were then mosaicked to form one single image in ArcGIS 10.2. It is then converted from geographic coordinate system to projected coordinate system using Universal Transverse Mercator (UTM) projection. The image falling within the district boundary was clipped using the digitized boundary map of Chennai. The final image of Chennai district is shown in fig.3 4. PREPARATION OF LANDUSE/LANDCOVER MAP The onscreen digitization of various landuse classes were then performed using ArcGIS 10.2 to prepare the landuse/landcover map. The various classes that were considered in the present study are built-up area, open land, water bodies and agricultural area. The landuse class field was added to the layer and the attributes were given appropriately. The area of various classes were obtained by generating topology. The thematic map showing landuse/landcover classes in Chennai is shown in fig.4. http://iaeme.com/Home/journal/IJCIET 1204 [email protected] N. Vaani, Aditya Anand Figure 3 The complete image of study area after mosaicking Figure 4 The landuse map of Chennai, Tamilnadu.