This is an interesting question and very relevant to people and animals in many different places on Earth. The first thing that I should note is that there is a lot of information on volcanoes out there and I can only briefly tell you about how they affect people.

The most important factor in determining the effects of a volcano eruption on the people, wildlife, and vegetation near the volcano is the type of eruption (which depends on the type of volcano). There are two basic kinds of eruptions and any volcano can erupt as some combination of these. The first type of eruption consists mostly of molten rock running over the surface of the earth like a thick liquid. This kind of volcano often comes from the ocean floor and some of the most familiar examples are lava flows that occur in Hawaii. In terms of effects on people and animals, these lava flows usually move slowly enough that animals can get out of the way in time. But they are very hot and bury any vegetation (or houses!) in their path and often can start fires that are dangerous.

The other extreme of the types of eruptions is very explosive. These volcanoes erupt with great force and the eruption is usually composed of a lot of ash, cinders, and rock. The heavier fragments fall close to the volcano but are very dangerous to any creature (or plant) where they land. The actual force of the eruption can knock down trees as happened with the eruption of Mt. St. Helens in Washington in 1980. The eruption of Mt. St. Helens also spurred large landslides because of the melting of the snow cap on its top and it soil washing away. Another dangerous possible effect from these volcanoes occurs when a cloud of extremely hot gas and ash (called a nuee ardente in French which basically means glowing cloud) comes rapidly from the volcano and burns away everything in its path.

Needless to say, there are many immediate ways in which these volcanoes can affect people and animals but longer term effects are also notable, especially in terms of fine ash blanketing everything (if you thought the dust that collects in your house was annoying, this will drive you crazy!) and the fine particles causing health problems.

These are just a few of the issues that come from volcanic eruptions. I encourage you to explore how volcanic eruptions affect people, animals,and landscapes. What issues might come up in the longer term once the ash has settled and the lava flowed cooled in the middle of town (this happened fairly recently in a town in the Congo which was cut in half by a lava flow)? Can you think of any ways in which volcanoes might be beneficial to people? In particular, think about what could be done with all of that heat energy.