Urbanization induced degradation of urban green space and its association to the land surface temperature in a medium-class city in India

A few recent studies revealed that the intensity of UHI is increasing in medium-class cities due to the rapid degradation of natural vegetation covers. This study explores the patch-level association between green space and LST on a spatial-temporal basis to reflect how green space concentration can influence the LST intensity. A total of 12 landscape metrics are incorporated to evaluate green space fragmentation and isolation in Raiganj City. Further, six metrics are included to show the LST patch compactness, and the complex relationship between these two is analyzed using multi-scale geographically weighted regression. It showed that a high proportion of green spaces with low fragmentation and isolation, particularly in 2000, was the source of sink areas in Raiganj. However, with the rapid removal of green spaces, fragmentation and isolation in the green spaces increased significantly in the subsequent years. It reduces the potentiality of green space as a cooling mechanism and strengthens the UHI effect over the city. This study suggests the requirement of a proper action plan, including a future land use & land cover planning map for the preservation and the net area increase of the compact green spaces. It will help to minimize the effect of UHI.