what is definition of alien vegetation in geography

Alien vegetation, also known as invasive or exotic vegetation, refers to plant species that are not native to a specific geographic area or ecosystem, but have been introduced either intentionally or unintentionally by human activities. These plants often outcompete native vegetation and can negatively impact the integrity and functioning of the ecosystem they invade. Alien vegetation may spread rapidly, displace native species, reduce biodiversity, alter nutrient cycling, and disrupt ecosystem processes.