Volcanoes have several effects on plants, animals and people and can negatively impact civilization because homes, fields, roads and buildings get damaged with ash and other debris. The ash can become so heavy that homes collapse. Volcano ash positively impacts human life by leaving the soil rich in nutrients. The gases released from the volcano can cause respiratory issues in those unable to evacuate from the region.
Although volcanoes produce large amount of toxic gases, most of the gas is diluted into the atmosphere unless the ash is thick. A volcano eruption destroys plant life surrounding the volcano. Even though the soil is left fertile, it can take several years for the foliage to return.
Pyroclastic flows (hot gas and ash mixtures), lava flows, tephra falls and atmospheric congestion can kill animals, especially livestock. Wildlife can die because of famine and forest fires that are related to the eruption. Volcanoes influence aquatic life by raising the acidity within the system. Fish may die from a rise in temperature or a loss in food supply. Volcano eruptions affect birds by interfering with migration patterns, roosting areas and the ability to fly. The ash is so heavy that it hinders a bird's ability to fly efficiently.