Quantifying carbon Stock and tree species diversity of green infrastructure of Varanasi, India

The world is undergoing rapid urbanization and experiencing its negative impacts, often due to the loss of urban green infrastructure. This study focuses on the green infrastructure of Varanasi city, India, and analyses current tree species diversity, and carbon storage in aboveground and belowground biomass and soil. The study calculated the biomass of urban green infrastructure because it serves as a carbon stock reservoir. As random sampling, data were collected from 24 sample plots across various urban green infrastructure sites via rigorous fieldwork. The biomass was then recorded using a non-destructive approach and a standard equation by King et al.2006. The diversity of tree species was recorded across urban green infrastructure sites, and was found to be higher in the BHU site, and lower in the MA site. The Pielou’s evenness index and Margellef’s richness index were found to be higher in the BHU site, while they were found to be lower in UPAC and MA sites, respectively. Aboveground biomass and total carbon stock were found to be high in the BLW site, with values of 1939.84 ton/ha and 7806 ton/ha, respectively, with trees having a larger girth circumference being the primary contributors. The findings of this study prove a better understanding of tree species diversity, biomass, and carbon stock of different green infrastructure sites of Varanasi city and generate evidence on how urban green space preservation and green infrastructure development may help to the countries' green economic transformation and sustainable, resilient, and low-carbon cities.