Conclusions

Temporal land cover analysisindicate 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 classifierindicate 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 hasincreased  by  more  than  638% mainly  from  the  conversion  of open areas and other areas including agriculture  land.Spatial metricsconsidering the area, edge, shape, aggregation  obtained  through  themoving  window  method  to  quantify  the urbanbuilt-up  land  density  provide  anefficientmethod  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 sprawlof built-up land has occurred on cost of fragmentation of various other classes for ex.agricultureland 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 1511billion 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 of water 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.