Impacts of Urbanization on Roadside Flora in Sargodha Region, Punjab, Pakistan

Abstract

Urbanization is one of the most important factors contributing to environmental change, and has a significant impact on the composition, diversity and health of roadside vegetation in rapidly growing cities. The present study aimed to explore the effects of urbanization on roadside flora of Sargodha region, Punjab, Pakistan with special focus on plant diversity, physiological responses and tolerance to urban pollution. Field surveys were carried out in selected urban, semi-urban and rural locations with different levels of urban development and traffic density. The species were identified and ecological parameters such as species richness, abundance and diversity indices were evaluated. Furthermore, the Air Pollution Tolerance Index (APTI) of dominant roadside plant species was evaluated by analyzing key biochemical and physiological properties including chlorophyll content, relative water content, leaf extract pH and ascorbic acid concentration.

The results showed that species richness’ and diversity decreased significantly as urbanization and traffic density increased. Pollution-tolerant species were more common in urban roadside habitats, and sensitive species were more common in less disturbed rural habitats. Increased concentrations of air pollutants and roadside dust were correlated with decreased chlorophyll content and changes in physiological traits of several plant species. Some species, however, showed greater tolerance by increasing their antioxidant activity and APTI values, suggesting their suitability for urban greenbelt development and phytoremediation applications. Soil analysis also indicated the presence of heavy metals and other pollutants in highly urbanised areas, which led to vegetation stress and ecological degradation.

The study reveals that urbanization has significantly affected the roadside flora of Sargodha and urges the need to conserve urban biodiversity by adopting sustainable urban planning and strategic plantation of pollution resistant plants. The results of this study will be useful for urban ecologists, environmental managers and policy makers to reduce the negative ecological impacts of urbanization and enhance environmental quality in fast growing areas of Pakistan.