INTERNATIONAL JOURNAL OF GEOMATICS AND GEOSCIENCES Volume 7, No 2, 2016

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1 INTERNATIONAL JOURNAL OF GEOMATICS AND GEOSCIENCES Volume 7, No 2, 206 Copyright by the authors Licensee IPA Under Creative Commons license 3.0 Research article ISSN Change in land useland cover and population dynamics: A townlevel Study of Ahmedabad city subdistrict, Aparajita Chattopadhyay 2 Doctoral fellow, International Institute for Population Sciences, Mumbai 2 Assistant Professor, International Institute for Population Sciences, Mumbai anks.sik@gmail.com ABSTRACT Change in Land UseLand cover (LULC) is a worldwide phenomenon. However, in certain places, the rate of change is expeditious, particularly because of increasing population and urbanization within a limited space. This study encompasses analysis of LULC change during the last two decades and its association with population parameters in one of the leading metro cities in India, i.e. Ahmedabad City subdistrict in Gujarat state in India. This study has used the Landsat images for LULC change detection and Census data of the same time period, to indicate the association of the total population, workforce, number of households, literacy, and caste stratification with LULC change. The peripheral change is observed maximum, with a high correlation of total and working population, indicating a shift of core to periphery expansion in Ahmedabad City subdistrict. Planners need to target environmental policies for the western side of the Sabarmati River, experiencing speedy change. Keywords: Land use; land cover; population; change detection; Ahmedabad; urbanization. Introduction Urbanization is a gift to human civilization if it is harmonized and designed in tune with nature s limit. According to United Nations Population Fund, world s urban population is expected to reach 8% by 2030 (as cited by Imhoff, Zhang, Wolfe & Bounoua, 200). The conversion of rural areas into urban areas through development is occurring at an unprecedented rate in the recent human record and thus, is having an obvious effect on the natural functioning of the ecosystem (Turner, 994). The first and foremost structural change of urbanization is being observed in the form of transformation of the land. In recent years, cities all over the world have experienced rapid urban growth because of an increase in the population and the flow of people from rural to urban areas. Larger towns and cities of the developing world are facing unplanned and uncontrolled growth within or outside the city limits. The process of urbanization in India gained momentum along with industrial revolution way back in the 970s followed by globalization. Forests were cleared, grasslands ploughed or razed, wetlands drained and croplands encroached upon under the influence of expanding cities, yet never as fast as in the last decade (Rehman, 2007). In 99, there were 23 metropolitan cities in India, which has increased to 35 in 200 and 53 in 20. India is witnessing urbanization and development, experiencing significant changes in LULC. These changes are important mainly for those emerging metropolitan cities that are growing fast, mainly for rapid economic structural changes. Most of the studies focus on those areas where Submitted on April 206 published on November

2 the magnitude of urbanization is very high and the alteration of the land cover is at an alarming rate. 2. Study area The city of Ahmedabad was founded in 4 AD as a walled city on the eastern bank of the river Sabarmati, now the seventh largest metropolis in India and the largest in the state of Gujarat. The population of the city has increased from 3.3 million in 99 to 5.8 million in 20 (Census of India, 20). Ahmedabad City subdistrict consisting of 8 subunits (towns/villages) lies between 22 55` and 23 08` north latitude and 72 28` and 72 42` east longitude. The area is devoid of any major physical features except the river Sabarmati, which is cutting across the city into two parts: eastern walled city and western Ahmedabad on either side of its banks (Figure ). Ahmedabad is showing remarkable developmental activities in terms of urbanization and industrialization in recent decades. Although not unique to Ahmedabad, the interaction of demographic and economic forces has resulted in a highly segmented spatial pattern of growth in terms of incomeclass and environmental qualities (Dutta, 2000). It is essential to study the trends and magnitude of changes in LULC as well as the population change in the towns and villages of the Ahmedabad City subdistrict for better policy and development planning. 3. Data sources and methodology: Figure : Location map of the Ahmedabad City subdistrict This study used satellite images derived from the United States Geological Survey ( Details of the images are as given in Table. For the analysis of population parameters at village and town level, population data have been collected from the District Census Handbook of Ahmedabad (Census of India, 99 and 200) and Primary Census Abstract (Census of India, 20). The study has incorporated the software 226

3 like Erdas Imagine 9.2, Arc GIS 0, and SPSS 20 etc. for the quantitative analyses of the acquired data to fulfil the objectives of the study. The methodology incorporated in land use and land cover change detection is represented by the flow diagram given in Figure 2. Here the LULC is classified into five categories as follows: Builtup area: Agricultural land: Vegetation cover: Water body: Fallow land: Residences, commercial centers, industrial zones, railways, highways, expressways and others Arable agricultural land and others Natural forest land, shrub lands, and others Rivers, ponds, lakes, reservoirs, permanent and seasonal wetlands and others Land without vegetation cover, exposed soil and others Figure : Steps involved in LULC mapping. Table : Satellite data used in the study. Image Acquisition date Resolution Path/Row LANDSAT5 TM Nov. 4, meter 49/044 2 LANDSAT5 TM Jan. 23, meter 49/044 3 LANDSAT5 TM Dec. 4, meter 49/ Results and Discussion Source: United States Geological Survey ( The study first looked into the LULC change followed by level and trends in population characteristics. Multivariate analysis is used to understand the association of population and LULC change. 4. Land UseLand cover change in the Ahmedabad City subdistrict Table 2 and Figure 3 indicate significant LULC change over time. These changes in LULC classes are associated with each other. The most significant change is observed in the builtup area. This area has occupied 28 percent of the total area of Ahmedabad City subdistrict in 99 and increased to 76 percent of the total area in 200. Such rapid change is a consequence of the high level of urbanization. The LULC category that is experiencing 227

4 significant negative change is agricultural land. The area under agricultural land is accounted 50 percent of the total area in 99 and reduced to seven percent of the total area in 200. In rural areas, the forested land is converted into agricultural land and later transformed into the builtup area as a consequence of developmental processes. Whereas in the core areas of the city forested part is transformed into a builtup area. The possible contributing factor behind this change is penetration of developmental activities from the urban areas to the suburban and rural areas. Rapidly increasing population and high inflow of migrants has resulted in the transformation of forested land in residential areas. Also, the new industries and factories are continuing to establish in the periphery of the city and have contributed in the process of land transformation. Figure 3: Supervised classification of the LANDSAT images of Ahmedabad Subdistrict Although the areas under the categories of the water body and fallow land shared very less percent of the total area, changes in these land uses are important to discuss. The area under 228

5 the fallow land is halved during 990 to 200. Whereas areas under water body are gradually increased, occupying a space of three sq.km in 990 and eight sq.km in 200. This is mainly because of the development of riverfront along the Sabarmati River and suitable management of water harvesting in the vicinity. Major LULC categories at village/town level have been calculated to understand the changes at micro levels (Figure 4). The changes are significant mostly at the outer part of the Ahmedabad City subdistrict. Towns experiencing a maximum change of the area under the builtup category are Nikol, Gyaspur, Naroda, Makarba, SaijpurGopalpur etc. While the Table 2: Estimation of area under different LULC categories and changes over time. Area change in area Land use Land from 99 to 200 cover category sq. percent sq. percent sq. percent in sq. km. km. to total km. to total km. to total percent Builtup Area Water Body Fallow Land Vegetation Cover Agricultural Land Total Area Figure 4: Changes in LULC categories over time Inner parts of the study area such as Ahmedabad MC (Municipal Corporation), Maktampur and Ranip have experienced less change in LULC. Towns accounting for maximum change in agricultural land are Chandlodiya, Ghatlodiya, Memnagar, Vastrapur etc. Highest change (around minus 80 percent) in vegetation cover has been observed at SaijpurGopalpur and Naroda towns. Probable factors related to the minimal change in core and maximal change in 229

6 the outer part include the availability of lowpriced land in the periphery region, nearness to the major transport network, open and vacant land compared to the inner part of the city. To understand the dynamism of population characteristics, the study has analyzed the level and percent change of selected parameters: total population, growth rate, population density, main workers, literates, number of households, scheduled caste population, and scheduled tribe population and overall sex ratio (Table 3 and Figure 5). Figure 2: Change in selected population parameters from 99 to

7 Sr. n o. 2 Name of the village/t own Ahmeda bad MC Ahmeda bad Contt. Table 2: Changes in selected population variables from 99 to 20. Cahn Percent Change from 99 to 20 ge in pop. Dens Gro ity wth Tota Main no. of Schedu Litera 99 rate( Popult Wor Househ led tes in%) ion ker olds Caste 20 Schedu led Tribe Sex Rat io Ranip Chandlo 359 diya Ghatlodi 2953 ya Memnag 694 ar Vastrapu r Makarba Sarkhej Okaf Vejalpur Maktam pur Gyaspur Shahwad i Piplaj Saijpur Gopalpu r Odhav Nikol Naroda Ahmeda bad City Taluka

8 4.2 Thematic superimposition of population over LULC map Thematic superimposition of LULC map and dot map of the population (Figure 6) indicates that the population is growing over those areas experiencing a significant increase in builtup land in the given period of twenty years. 4.3 Correlation matrix for selected parameters of population and LULC Table 4 indicates the association of change in LULC classes with the change in some important population variables. The significant strong positive association exists with a change in built up area and change in number of literates and number of households. Agricultural land has declined over time. Same is the case for vegetation cover i.e. with an increase in proportion literate and percent workers; in the given area vegetation cover has reduced noticeably. As obvious, population increase has a high association with an increase in main workers, literates, number of households, indicating an inflow of working class people in the growing outer part of Ahmedabad city subdistrict. Figure 3: Thematic Superimposition of LULC map and Total Population. 232

9 Table 3: Correlation matrix between percent change in selected LULC categories and population variables from 99 to 20. Builtup area Agricult ural land Vegetati on cover Total Populati on Main Workers Literates Househo lds Schedule d Caste Schedule d Tribes Built up area Agric ultura l land 5. Summary and Conclusion * ** *** Veget ation cover * * Percent change in. Total Popul ation *** 0.96 *** 0.97 *** *** Main Wor kers The present study has assessed LULC changes and variation of population characteristics in Ahmedabad City subdistrict in Gujarat state in India for a time period of 99200, using GIS and statistical techniques. A multitemporal analysis is applied to the Landsat images for change detection and rate of change is calculated from Census data (99 to 20) for the same time period. The association is studied with the use of multiple correlation and linear regression techniques. The study area has experienced rapid change, particularly in the builtup area, agricultural land, and vegetation cover. From 99 to 200, builtup area of Ahmedabad City subdistrict has witnessed an overall increment of 73 percent and such huge change has contributed mainly from agricultural and forest land. The magnitude of *** *** 0.85 *** Sex Ratio (Note: * = p < 0.05, ** = p < 0.0, *** = p < 0.00) Lite rate s 0.9 4* ** 0.7 4** * Hous ehol ds *** Sch edu led Cas te Sch edu led Tri bes Se x Rat io 233

10 changes in LULC as well as in population parameters has recorded high in specific situated at the outer part of the Ahmedabad City subdistrict. The process of change (in LULC and population) has been shifted from core to periphery region. The western side of the Sabarmati River has developed in the recent past and has experienced significant transformation in LULC and population dynamism as compared to the eastern side of the Ahmedabad city subdistrict. Thus, for a balanced development in the rapidly growing periphery of the subdistrict, there is a need for suitable planning that can help a balanced expansion, keeping in mind the limits to growth. 6. References. Dutta, S. S. (2000). Partnerships in urban development: a review of Ahmedabad s experience. Environment and Urbanization, 2(), pp Imhoff, M. L., Zhang, P., Wolfe, R. E., & Bounoua, L. (200). Remote sensing of the urban heat island effect across biomes in the continental USA. Remote Sensing of Environment, 4(3), pp Rahman, A. (2007). Application of remote sensing and GIS technique for urban environmental management and sustainable development of Delhi, India. In Applied remote sensing for urban planning, governance and sustainability. Springer Berlin Heidelberg. pp Registrar General of India. (99). Census of India 99: Primary Census Abstract, Ahmedabad. Government of India. New Delhi. 5. Registrar General of India. (200). Census of India 200: District Census Handbook, Ahmedabad. Government of India. New Delhi. Retrieved from: 6. Registrar General of India. (20). Census of India 20: Primary Census Abstract, Ahmedabad. Government of India. New Delhi. 7. Turner, B. L. (994). Local faces, global flows: the role of land use and land cover in global environmental change. Land Degradation & Development,5 (2), pp