Nitrogen deposition and fire regime suppression are key drivers of vegetation change in urbanising grasslands. In the natural grasslands that surround Melbourne, Australia, some native species have become rarer (decreaser species) across the landscape, while others have become more widespread (increaser species).
In this study, Zeeman and Morgan examine experimentally the response of increaser and decreaser native plant species to nitrogen addition/depletion, and the presence/absence of annual disturbance to the vegetation. Their results provide evidence that by affecting plant growth, nitrogen deposition and declines in disturbance frequency could be key drivers of biotic homogenisation in urban grasslands.
Zeeman, B. J., & Morgan, J. W. (2018). Increasing and declining native species in urban remnant grasslands respond differently to nitrogen addition and disturbance. Annals of Botany, 121(4), 691–697. https://doi.org/10.1093/aob/mcx200