Evaluating The Impact of Roads On The Diversity Pattern And Density of Trees To Improve The Conservation of Species

Abstract

Abstract Roads have a great impact on the structure and functioning of the diversity pattern in an ecological environment and play the role of altering biotic and abiotic factors. Clusters of plants grow along the roadside due to the interplay between the arrival of propagule and seedling establishment, which depends on the road’s specifications, land pattern, and road administration and protection practices. It is very important to study the diversity pattern in a metropolitan city to improve the ecological environment. Karachi is one of the world’s largest and fastest-growing metropolitan cities; however, little is known about the urban forest of the area. In Karachi, which is in the province of Sindh, Pakistan, roadside trees along various road types (e.g., wide, medium and narrow roads) have been studied. Based on a field study, various measures of diversity were utilized to investigate the diversity of tree species on different types of paths. A total of 180 plots, divided into three primary road groups, were surveyed. The highest quantity of tree biomass per unit area was found on wide roads, followed by medium roads. On narrow roads, the least biomass was detected. A single species or a limited number of species dominated the diversity of species. Conocarpus erectus was the most dominant non-native species along all types of roads, followed by the species Guaiacum officinale. A total of 76 species (32 non-native and 44 native) that were selectively spread along the roadsides of the city were studied. There was a significant difference in phylogenetic diversity (PD), phylogenetic mean pairwise distance (MPD) and phylogenetic mean nearest taxon distance (MNTD) between wide, medium, and narrow roads. Management practices have a significant positive correlation with diversity indices. Our study identified patterns of diversity in roadside trees in Karachi. It provided the basis for future plant conservation planning, such as the conservation of plant species, the maintenance of plant habitats, and the coordination of plant management in Karachi.