Geo-Environmental Appraisal For Studying Urban Environment And Its Associated Biophysical Parameters Using Remote Sensing And GIS Technique
Keywords: Urban Environment, SAVI, MNDWI, IBI, LST, IRS Resourcesat-2 LISS-3, Landsat TM/ETM+/8, CORONA
Abstract. This study investigated the influences of urbanization on urban ecological and thermal environment as well as the relationships of all the biophysical parameters with each other utilizing multi-temporal datasets of CORONA (1967), Landsat TM (1992 and 2009), Landsat ETM+ (2002), IRS R2 LISS-3 (2012) and Landsat 8 (2014). The urban environmental issues related to land use and land cover, greenness, surface wetness and impervious surface were assessed using change detection, SAVI, MNDWI and IBI models respectively. The land surface temperature (LST) was also retrieved from thermal infrared band of each Landsat TM, ETM+ and Landsat 8. Based on these parameters, the urban expansion, urban heat island effect and the relationships of LSTs to other biophysical parameters were analyzed. Results indicate the area ratio of impervious surface in Pune sub-urban zone increased significantly, which grew from 1.41 % in 1967 to 8.47 % in 1992 and further to 22.45 % and 44.7 % in 2002 and 2014 respectively. Simultaneously, the intensity of urban heat island increased in observed years. A correlation analyses revealed that, the association of impervious surface to other two variables i.e. greenness and land surface wetness is negatively correlated (R2 = 0.616 and 0.607 respectively). Whereas, LST possessed a strong positive correlation with impervious surfaces (R2 = 0.658).
The present study provided an integrated research approach and the outcome of the study is very useful in environmental modelling and sustainable development of urban areas and natural resources conservation.