Green infrastructure of Varanasi, an ancient city of India

Abstract

Trees are an essential component of the urban green infrastructure (UGI) as they mitigate the negative impacts of urbanisation on human well-being. However, little is known about the richness, density, and botanical composition of the green infrastructure, particularly in places like Varanasi city of Uttar Pradesh with rapid and unplanned rate of urbanization. This study assessed the tree species richness, density, and composition patterns at eight sites in Varanasi city, encompassing rural, sub-urban, peri-urban, and urban areas with varying green cover. A total of 189 trees were recorded, belonging to 46 species, 39 genera, and 23 families. Of these 85% were native, while 15% were exotic. The densities of exotic species were higher in Sarnath and Indane Gas Plant (IGP) campuses. Seven species were common to all sites (Ficus religiosa L., F. benghalensis L., Eucalyptus globulus Labill., Syzigium cumini L., Mangifera indica L., Azadirachta indica A. Juss, and Artocarpus heterophyllus Lam). Flower-yielding species were maximum at the IGP campus site, whereas fruit and fodder yielding species occupied the Banaras Hindu University (BHU) site. The Jaccard similarity index was high between peri-urban Sarnath and Ramnagar sites. Tree biomass, carbon storage, and carbon sequestration were higher in the Banaras Locomotive Works (BLW) site as compared to other sites. Our findings imply that in order to improve the ecological quality of urban areas, citizens and city managers should develop endemic heterogeneous green infrastructure by selecting fast-growing and those that potentially will develop a higher girth class. © International Society for Tropical Ecology 2025.