Yes, invasive species can be a big problem. Here is a list of invasive plants with description and recommended measures (for German gardeners).
Some of them are indeed very dangerous some others less (by the way a few nowadays even play important roles in the current ecosystems even if being invasive).

Apropos I think you made a little typo, you wrote:
"Human influence on invasive species"
Correct should be:
"Human influence AS invasive species" :-)
Just kidding, but sometimes we forget who causes more damage than all invasive animals and plants together ...
Have you ever been in the zoo of Frankfurt? In the building of the predators you come to a sign announcing the most dangerous animal ... then, if you continue to walk, you will find yourself in front of a mirror ... :)