The vegetation zones describe different combination of plants, which grow over large regions.

Plants are a fine indicator of climate, as they depend on the weather to grow. They need:

They also need nutrients from the soil to build their tissues. These nutrients are dissolved and transported by water. The soils also form through the chemical interaction of water with the soil materials and the temperature influencing these processes.
Click on the different types of vegetation (menu on the right) to learn more.