In this paper an integrated approach using satellite data and GIS techniques in conjunction with socio-economic data is used to assess urban environmental issues in Delhi. Delhi’s current population of 13. 8 million is growing rapidly, and is projected to reach 22. 4 million by 2021. The issues addressed in this paper include: changes in land use/land cover changes in surface temperatures for 2001 and 2005; solid waste generation, collection and its management; and industrial pollution (i. . air, waste water and noise). The results show that Delhi is developing very rapidly mainly in the west, south-west and eastern sides. The study shows that a 122% increase in highly dense residential area was recorded during last decade in Delhi. There was a reduction (17%) in agricultural land because of urban expansion in the fringe areas. The pollution load has increased in terms of air, water, noise, and solid waste generation and disposal, etc.
The thermal infrared (TIR) satellite data of Delhi clearly shows that there was a 1-2°C increase in surface temperature in just 4 years that is a subject matter of concern. India. Key words: Population, development and environment; Geo-spatial approach; Delhi; 1. Introduction There is an unequal urban growth, which is taking place all over the world, but the rate of urbanization is very fast in the developing countries, especially in Asia. In 1800 A. D. , only 3% of the world’s population lived in urban centres, but this figure reached to 14% in 1900 and in 2000, about 47% (2. billion) people were living in urban areas. India no longer lives in villages and 79 million people were living in urban areas in 1961, but it went up to 285 million in 2001. In India and China alone, there are more than 170 urban areas with populations of over 750,000 inhabitants (United Nations Population Division, 2001). Statistics show that India’s urban population is the second largest in the world after China, and is higher than the total urban population of all countries put together barring China, USA and Russia.
In 1991, there were 23 metropolitan cities in India, which increased to 35 in 2001 (Census of India, 1991 and 2001). The prominent ones are Delhi (13. 78 million), Mumbai (13. 22 million), and Chennai (6. 42 million). There is a mass migration of people from rural areas to cities and also from smaller to larger cities and then to metropolitan centres like Delhi, Bombay, Kolkata, Bangalore, and Chennai. The major cause is the search for better employment opportunities in these urban centres in comparison to neighbouring States.
As urban population increases, the demand of land for various urban activities also increases. The process of urbanization in India gained momentum with the start of the industrial revolution in the 1970s followed by globalization in the Forests were cleared, grasslands ploughed or grazed, wetlands drained and croplands encroached upon due to expanding cities, yet never as fast as in the last decade (Rahman, 2007a). This exponential population growth has wreaked havoc on human life in the city environment.
The doubling and tripling of urban population in practically all major cities and towns and the consequent strain on existing systems has manifested in environmental chaos. Every major city of India faces the same proliferating problems of urban expansion, inadequate housing, poor transportation, poor sewerage, erratic electric supply, and insufficient water supplies. An increasing number of trucks, buses, cars, three-wheelers and motorcycles all spewing uncontrolled fumes, all competing for space on city streets already jammed with jaywalking pedestrians, rickshaws and cattle.
The phenomena of rapid urban economic growth and urbanization are the main culprits, which besides bringing higher standards of living, has also brought problems related to the growth of dense and unplanned residential areas, environmental pollution, lack of services and amenities, solid waste generation, and growth of slums. Population growth and in-migration of poor people, industrial growth, inefficient and inadequate traffic corridors, and poor environmental infrastructure are the main factors that have deteriorated the overall quality of the city environment.
The future of Delhi in the light of its past experiences, current trends, and development initiatives is one of the important issues which shows different social and physical factors affecting the housing and quality of life in Delhi (Mishra et al. , 2001). After independence, when Delhi witnessed a large influx of migrants, within a very short time, the population of Delhi increased more than two fold. To house such a large migrant population, the city has to expand. The rate of expansion is very fast, unplanned, uncontrolled and most of them are illegal (Rahman and Agarwal, 2007).
Mushrooming of illegal construction has become a day-to-day phenomenon in the fringe areas of all big and medium size cities in India. The level of air, water, and land pollution has increased because of poor environmental management. This has a direct impact on the quality of the urban environment, affecting labour productivity and overall socio-economic development. India’s urban air quality ranks among the world’s worst. Vehicles are the major source of this pollution, today with more than 5 million cars, trucks, buses, taxis, and rickshaws already on the roads in the country’s capital New Delhi alone.
Each 184 ATIQUR RAHMAN ET AL. urban centre has a number of environmental problems with varying scale and scopes which are influenced by factors such as size of population and its density, climatic conditions, water resources and the flora and fauna in and around the urban centre (Hardoy et al. , 1997). The state of the urban environment all over India is deteriorating so fast that the sustainability of the cities is threatened. In metro cities like Delhi, the land environment is under stress due to the pressure of rapid urbanization.
As the cities expand and population increases, the resources, which are limited, are shared. The lack of services such as water supply, sanitation, drainage of storm water, treatment and disposal of waste water, management of solid and hazardous wastes, supply of safe food, water and housing are all unable to keep pace with urban growth. In Delhi three organizations, the New Delhi Municipal Corporation (NDMC), the Municipal Corporation of Delhi (MCD), and the Delhi Development Authority (DDA), are looking at different aspects of Delhi’s growth and development under the overall supervision of the Delhi Government.
But often one organization blames the other for deteriorating conditions and the growing threat to the city’s sustainability (Tiwari, 2003). There are also Mayors, Municipal Commissioners, and ward Counsellors/Representatives who are responsible for managing their respective areas. However, even these people are not doing what has to be done to protect the city environment. This is mainly due to the lack of up-to-date spatial data, skill to use the data properly, and commitment to save and protect the environment (Raman, 2007b). There is no tax for environmental management.
In fact it would be good to make some sort of environmental tax that can be levied on the industrial units and transport owners. This collected revenue can go directly to local administrators and environmental managers. It is fair to say that only one part of Delhi has a good level of services – namely the NDMC enclave – and rest of the huge area of Delhi suffers from the above mentioned problems. The increasing demands for information in urban planning and management sectors call for the application of remote sensing for sustainable development of urban areas.
So in this context integrated geo-spatial technologies such as remote sensing (RS), geographic information system (GIS) and global positioning system (GPS) can contribute to interactive operations that would be an asset for assessing, understanding, and mapping utility and AN ASSESSMENT OF URBAN ENVIRONMENTAL ISSUES… 185 service facilities, as well as solving complex urban environmental problems. By utilizing remote sensing data and implementing GIS mapping techniques, changes in urban extent can be monitored and mapped for specific developmental projects.
Creating linkages between remote sensing data and socio-economic data obtained on the ground from household surveys has been recognized as one of the major challenges of land use/land cover change studies (Rindfuss et al. , 2003). Satellite remote sensing, with its repetitive coverage and multi-spectral (MSS) capabilities, is a powerful tool for mapping and monitoring the emerging changes in the urban core and peripheral areas. The loss of agricultural land because of rapid urbanization has been detected using remote sensing techniques in some cities of India, such as Hyderabad, Madras, and Nagpur (NRSA, 1994).
Standard atmospheric and geometric parameters were estimated using FLAASH 4. 1 and were applied to each of the images for atmospheric correction. The flow diagram of multi-spectral data processing and estimation of surface temperature is shown in Figure 3. The procedure involves successive steps that are described in the flow chart. Figure 3 – Flow chart of methodology for surface temperature estimation ASTER satellite datasets Day time dataset of 2001 & 2005 Night time dataset of 2001 & 2005 Geometric and radiometric correction MNF Transformation Covert to spectral radiance
Digital image classification based on classification scheme using MLC classifier Computation of surface temperature and emissivity using TES algorithm Land use/cover of 2001 Land use/cover Accuracy Assessmernt of 2003 One surface temperature and five One surface temperature and five emissivity maps of01 Oct 2001 emissivity maps of 2nd Oct 2005 . View Image Histogarm and scattergram Geostatistical tools using for analysis Evaluate the correlation among LULC and surface temperature Temporal analysis of Surface temperature image 2. 5. Methodology for solid waste, air, waste water and noise pollution
The map of Delhi collected from the Delhi Development Authority (DDA) was scanned, geo-referenced using Survey of India (SoI) topographical sheets at the scale of 1:50,000, and digitized in ArcGIS software. Various thematic layers were generated in the GIS using secondary data collected from Government departments like CPCB and MCD, etc. 190 ATIQUR RAHMAN ET AL. 3. Results and discussion 3. 1. Demographic profile of Delhi The national capital is attracting people from all parts of India. Delhi is a mini India with the largest number of immigrant communities of any city.