Alien flora of Pakistan: taxonomic composition, invasion status, geographic origin, introduction pathways, and ecological patterns

Inventories of alien species are important for monitoring and understanding the dynamics of invasion, which is crucial in devising management policies. The present study prepared a comprehensive inventory of alien plant species in Pakistan. Based on field observations, published work, scientific reports and online databases, 400 alien taxa were identified (83 families, 265 genera), 180 of which were classified as casual alien, 117 as naturalized, and 103 as invasive. Poaceae (61 taxa) and Asteraceae (46 taxa) were the richest families, while Ipomoea (9), Amaranthus (8) and Euphorbia (8) were the genera with the largest numbers of alien taxa. The greater majority of alien species were annuals (32