Volcanoes can destroy an ecosystem by killing the plants, wildlife, and affect the weather. These are major effects that can destroy an ecosystem. We need plants for medicine purpose as well as tree's for fresh breeze. The volcanoes can rejuvinate the ecosystem by change in an arid volcanic lansdcape. An geological risk that could have a negative impact is an earth quake due to climate change. An earth quake can cause a stunami in california, new york city, etc..