Software used
ARC/INFO & ARC/MAP (8.3 Version) AND Geomatica (8.2 Version)
Methodology
It has been demonstrated in India and many other countries that remotely sensed data can be used to for mapping and monitoring the changes on the land surface over a period of time. The detection of abrupt changes is possible using satellite images in many cases where the changes produce an extreme visual contrast between the old and the new. The use of both image processing and geographic information techniques has been applied to the different maps and images for understanding the sprawl. The methodology can be divided in to the following steps:
- Firstly the thematic maps collected from various different sources were scanned with scanners and converted in to tiff files.
- Secondly, using the image processing software EASI/PACE the maps were geocoded using ground control points with the RMS error at the acceptable level.
- Thirdly, the digital data was loaded from CD’s and geocoded with the help of the previously geocoded maps.
- Fourthly, the geocoded maps were enhanced spectrally for better visual and digital appreciation.
- The enhanced geocoded images were extracted with respect to the Bangalore urban district boundary as available in the toposheets.
- Then, visual interpretation was carried out on these maps and images and the boundary of the city’s outer boundary was extracted from each map in a GIS environment.
- Finally, the entire vector layers extracted from each map was placed one over the other to know the increase in the city area as to how much the city has sprawled since its inception.
- The Bangalore-Mysore corridor region was classified using supervised classification technique and with its help the growth over 26 years in the entire region in the urban was understood.
Results
Geoinformatics Database
The data related to population, literacy, civic amenities like, water supply, road length, electrification, cultural details like the contribution of schedule caste and schedule tribe to total population, details on literacy, personal details of telephone calls, general population details, sex ratio etc., were used to create a urban information system for the major towns and cities of the study area to notice and appreciate the change in these parameters on a decadal basis from the year 1971 to 2001. The decadal trend in which the growth of these various information’s have been attached to the spatial data.
Landuse Changes
It is a noticeable fact that the living conditions are expensive, which include the bare essentials like food and shelter even then people motivated by the thought of better education, good jobs, speculative thought are moving in to overcrowded cities like Bangalore, Mandya and Mysore. This has given a feature to the planning community known as sprawl or spread of the urban area in to the rural area. The transformation of the fringe area in to predominantly urban mostly along the roads is noticeable change. This has lead to the development of high-class residential areas like Indiranagar, in Bangalore City. The development of exclusively industrial town like Bidadi is also noticed.
The urban area has not just expanded it has expanded at the cost of other land uses. The Table below shows the amount of area from other land uses, which has been incorporated in to the sprawling urban region. The 13 major towns of the study area have engulfed about 196.19 square kilometer of agricultural area.
| Increase In Urban Area |
Sq. Kms |
| Total Urban Area In 1973 |
164.72 |
| Water Bodies |
10.33 |
| Vegetation |
6.18 |
| Wasteland |
1.89 |
| Agricultural Area |
196.19 |
| Total Urban Area In 1999 |
379.33 |
The steady growth in various factories based on Motor vehicles, Information technology, Computers, specialized services of quaternary and quinnenery nature have risen to a great extent providing exclusive and highly specialized nature of services. Leading to special type of employment recruitment and also socio- cultural services to patronize such people which include high profile clubs, bar and restaurant, discotheques, restaurants specializing in foreign delicacies, special dress boutiques, makeup shops, sports complexes, malls, massage parlors etc.
Demographic and Infrastuctural Changes Through the Decades
There has been a high rate of increase in the number of medical services, the banks, transportation services, electrification, and government water supply, the basic structure of workers i.e. in the primary, secondary and tertiary sectors. In 1991 of the total male working population 53.72% were engaged in Tertiary activity and of the total female working population 57.93% were in tertiary sector. Literacy is considered the mark of prosperity and development. In the study area there has been steady increase in literacy, currently it is 75.61%. There has been steady change in the working population in the primary, secondary and tertiary sectors respectively which have shifted towards non agricultural activities over the years. The change in the whole population in the major towns and cities along with the growth in literacy rate are listed in the appendix.
Conclusions
- The Geoinformatics database, which has been created using various details from census reports from 1971 to 2001 for the major towns and cities, are found useful to do mainline analysis and predict the growth of the settlement in the future. A GIS data modeling by predicting the future trend by knowing the past and present can be done successfully.
- Demographically there is high growth of population and high rate of migration from surrounding regions and from other parts of country and abroad to Bangalore. The sprawl of the urban area is basically on to the rural fringe area engulfing large amount of agricultural land. The workers participation ratio has shifted from primary activity to secondary and tertiary activity which has caused increase in their economic standard along with their residence and other establishments which has led to apartments rather than solitaire houses. Space management and vertical population growth is a noticeable phenomenon.
- The settlements are enlarging in size and shape taking a near circular shape. The cities of Mysore and Bangalore are taking a near circular shape. They have started to engulf the nearby settlements, Bangalore has engulfed Kengeri Township.
- The spatial spread of the Bangalore City has been calculated from the processing of multitemporal data. The first growth spur can be traced from 1911 to 1977 which, was after a period of 66 years. The second growth spur is between 1991 to 2002 where, the total urban area has more than doubled. This clearly indicates the role which all the IT, Computer, Fashion, Dress making, Educational institutions have played.
| YEAR | TOTAL URBAN SPRAWL AREA IN SQ KMS |
| 1537 |
10.38 |
| 1895 |
35.80 |
| 1911 |
60.11 |
| 1972 |
132.57 |
| 1980 |
185.59 |
| 1986 |
218.27 |
| 1991 |
246.96 |
| 2002 |
508.03 |