Urban green-cover and the environmental performance of Chennai city

Chennai city the capital of Tamil Nadu is located in southeastern India. Its average population growth rate is 25% per decade, which recurrently alters the city's land-cover particularly the receding green-cover distressed the city's self-renewal capacity, in terms of groundwater recharge, pollution sequestration and microclimatic amelioration. This has been appraised by means of a GIS model. This model was developed using three sets of green-cover associated parameters, namely air quality amelioration, hydrological process regulation and microclimatic amelioration. The outcome confirms the difference in the city's environmental performance between the 1997 and 2001. At some parts of the city, due to the green-cover change, the extent of modification was 38%, in terms of mean percent change in all three sets of parameters mentioned earlier. Through coefficient of correlation (r) method, relationship between green-cover change and environmental performance change are checked. It confirms positive relationship (r = 1) in all parts, except at few places.