Conclusion

Temporal land cover analysis indicate of decline in that the vegetation by about 75.03%, while the area under non vegetation has shown an increase of 121%. Land use analyses for the period 1977 to 2010 done through the Gaussian maximum likelihood classifier indicate that the area under built-up has increased from 3.6 (1977) to 25.06 (2010)%. During the past four decades the total urban (built-up) area has increased by more than 638% mainly from the conversion of open areas and other areas including agriculture land. Spatial metrics considering the area, edge, shape, aggregation obtained through the moving window method to quantify the urban builtup land density provide an efficient method for predicting the urban growth pattern. This has aided in visualizing and quantifying the burgeoning urban footprint at Delhi. The analysis also revealed of sprawl and the process of densification has happened around the city centre and has spread out of the core during 1990’s and have started to get clumped during 2010. Aggregation and sprawl of built-up land has occurred on cost of fragmentation of various other classes for ex. agriculture land and urban green spaces. Visualisation of urban growth helps the urban planners and decision-makers in formulating appropriate development strategies to mitigate the potential impacts on the urban environment.

Government needs to play a pivotal role in planning sustainable cities with the healthy urban environment and sustenance of natural resources (vegetation, water bodies and open spaces). The results of the current analyses highlight of the significant changes in land cover with the decline in vegetation, water bodies, crop and fallow land. This necessitates an integrated approaches in urban planning to ensure the sustenance of water, moderation of micro climate, etc. Conservative urban planning would take into account the sustenance of natural resources and people’s livelihood aspects. The current demand of water as per the recent estimates of Delhi Development authority, is about 1511 billion liters with the shortfall of about 450 billion liters. The annual rain water harvesting potential is about 900 billion liters. Further augmentation of resources is possible through the revival of water bodies that helps in recharging ground water aquifers. Ground water contributes substantially in newly developed localities in Delhi due to insufficient supply ofwater from Yamuna River. In order to ensure groundwater recharge, the government authorities need to maintain minimum vegetation cover in the region apart from recharge through percolation pits and rain water harvesting. A green belt or native vegetation on either side of banks help in arresting the soil erosion, remediation, minimisation of salinity and improvements in water quality. This entails holistic approaches in urban development to appropriately preserve the areas of various land-use classes considering the ecological and environmental services for maintaining the inter-generational equity.