Events such as earthquakes, landslides, and volcanoes are all major disturbance agents which can create new ecosystems with extremely different biota. In many parts of the world landslides have been linked to drastic changes in vegetation. Just like landslides volcanic eruptions are also present in many parts of the world and may be responsible for large scale vegetation changes. Recent events such as the eruption of Mt. St. Helens are one example of how volcanic activity has shaped many ecosystems around the world.