Urban Tree Diversity and Conservation Challenges in Thiruvallur District, Tamil Nadu, India

Abstract

Background: Urbanization has profoundly altered natural vegetation patterns, leading to the introduction of exotic species and the decline of native flora. Urban green spaces play a vital role in sustaining biodiversity, regulating climate, and improving human well-being, yet region-specific studies remain limited for many rapidly developing districts in India. Aims: The study aims to document and analyze urban tree diversity in Thiruvallur District with reference to species composition, nativity, habitat preference, and IUCN conservation status. It also seeks to provide baseline information to support urban biodiversity conservation and sustainable planning. Study Design:  A descriptive and systematic floristic survey design was employed to assess arboreal diversity across different urban land-use types. The study integrates taxonomic documentation with ecological and conservation-based analysis. Place and Duration of Study: The research was carried out in Thiruvallur District, Tamil Nadu, an ecologically diverse and industrially expanding region within the Chennai Metropolitan Area. Field surveys were conducted over a two-year period from January 2023 to December 2024. Methodology: Extensive field surveys were undertaken in urban, peri-urban, and industrial zones, focusing on avenue trees and public green spaces. Species identification was confirmed using standard floras and Plants of the World Online, while nativity, invasive status, and IUCN Red List categories were compiled from published sources. Results: A total of 151 tree species belonging to 94 genera and 43 families were recorded, with native species predominating. Most species were classified as Least Concern, while several Vulnerable and Endangered taxa of high ecological and economic value were identified, indicating priority conservation needs. Conclusion: The study demonstrates that Thiruvallur District supports substantial urban tree diversity despite intense anthropogenic pressure. Strategic conservation of native species, control of invasives, and ecologically informed urban forestry practices are essential for sustaining ecosystem services and enhancing urban resilience.