Have you ever noticed how different places have different types of plants and weather? In this lesson, you’ll learn about the five major vegetation regions in the world and what makes each of them unique.
Jenna is in a museum dedicated to the study of the Earth. In the museum, there is a series of rooms that lead into one another. As she wanders through, Jenna notices some distinct differences. In some rooms, there are lots of trees and other types of plants. In other rooms, there’s nothing but ice.Jenna is looking at different vegetation regions, or areas with distinct types of plants, soil, and weather patterns. The word ‘vegetation’ just means ‘plants,’ so a vegetation region is an area with a specific type or types of plants.
A vegetation region is determined by a number of factors, including climate, soil, and the slope (or angle) of the land. There are five vegetation regions in the world: forest, grassland, tundra, desert, and ice sheet.Let’s take a walk with Jenna through five rooms representing each of the five vegetation regions, and look at what makes each one unique.
The first room that Jenna enters is very familiar to her. There are lots of trees, and it is cool and shady. It reminds Jenna of where she grew up in the Northeast.
An area with trees grouped so that their leaves shade the ground is called a forest. Forests can have many different climates, from very warm to very cool. Where Jenna grew up, the seasons changed throughout the year, so that sometimes it was warm and sometimes it was cool.
There are two types of forests: deciduous and evergreen. Deciduous forests are made of trees whose leaves change with the seasons. In the Northeastern United States, where Jenna is from, deciduous forests are common.
Tourists flock to that area every fall to watch the leaves change colors.They couldn’t watch the leaves change color in the other type of forest, evergreen forests, which are made of trees whose leaves don’t change color and are green year-round. Evergreen forests can sometimes resemble a Christmas tree farm, because there are evergreen trees everywhere!Whether at the equator or in the Arctic Circle, whether deciduous or evergreen, a forest always has trees grouped closely together so that the leaves shade the ground.
Jenna moves out of the tree room and into a different room.
Here, she notices that the room looks very open. There is grass and some flowers, but only a couple of trees. A grassland is a flat and open area where grass is the predominant type of vegetation.
As its name suggests, grasslands are full of grass!Jenna recognizes the grassland room as being similar to the place where her cousin is from, the plains of North America. Indeed, much of the Great Plains region of the U.S. is grassland. Standing in the plains, you can see for miles and miles because the land is flat and there aren’t very many trees to block your view.The plants in the grasslands vary depending on the temperatures of the area where they are located.
In cold climate grasslands, like in Northern Europe, the land is covered with tough vegetation that thrives all year, like oats and weeds. Warmer climate grasslands, like those in the Great Plains, are covered with seasonal vegetation that changes as the seasons change.Finally, a tropical grassland that has a very hot climate is called a savanna and is common in Africa. The savanna is covered with grasses that can survive very hot temperatures.
Jenna moves into the next room, and is surprised to see a place with no trees, and only a few shrubs.
It looks to her like the area near the top of a mountain that she once climbed with her father.A tundra is an area where tree growth is difficult because of cold temperatures. Tundras are covered with mostly shrubs, grasses, and mosses. There are no trees in a tundra and in general there are fewer types of vegetation than forests and grasslands. This makes sense: if a tundra is in a very cold area, there are fewer types of plants that can survive the freezing temperatures.There are two types of tundras in the world. An alpine tundra can occur anywhere on Earth at high altitude.
When Jenna was climbing the mountain with her dad, she remembers that he said that the tundra was above the tree line. That is, it was above the place where trees could grow. This is an alpine tundra; that is, a tundra created by the conditions at high altitude.The other type of tundra is the arctic tundra, which occurs at or near the Arctic Circle.
As with an alpine tundra, the arctic tundra is classified by very cold temperatures. But instead of the cold being a result of high altitude, in the arctic tundra, the cold is caused by being near the top of the Earth.
Jenna is cold in the tundra room, so she moves into the next room. This one is warmer. In fact, it feels pretty hot. But more than that, it is dry. There are very few plants and those that are there look pretty odd compared to what she’s seen in the forest, grassland, and tundra.
Jenna is in a desert, or an area with less than ten inches of rain per year. Because of the lack of rainfall, the soil in a desert is often sandy or rocky. Both the unique soil and the dryness of the desert lead to plants with long roots, small leaves, and stems that store water.
For example, Jenna notices some cactus plants in the desert. These are very common.Jenna is relieved to be out of the cold tundra and in a nice, hot desert. But deserts aren’t always hot.
In fact, the largest desert in the world is the Antarctic desert, which takes up the entire continent of Antarctica. There, the land is barren and made up of mostly rock.
Jenna makes her way from the desert room into the very last room. Here, the temperature is very cold and the ground is slippery because it is covered with ice. An area where a glacier covers the land for more than 20,000 miles is called an ice sheet. Because of the cold and ice, there is no vegetation on an ice sheet.Notice that there’s more to being an ice sheet than simply having ice or glacier around.
There has to be ice covering the ground for a very big area: at least 20,000 miles! Because of that, there are only two ice sheets in the world: in Antarctica, where the ice sheet covers the desert, and Greenland. Anywhere else in the world, there may be glaciers and ice covering the land, but it’s not an ice sheet vegetation region.
A vegetation region is an area with a distinct type of plants, soil, and weather patterns. There are five major vegetation regions in the world.
- A forest is an area where the trees are grouped so closely that their leaves offer shade. Forests can be deciduous, covered mostly with trees whose leaves change with the seasons, or evergreen, covered mostly with evergreen trees.
- A grassland is a flat and open area where grass is the predominant plant.
- A tundra is an area where tree growth is difficult because of the cold weather, and can be divided into alpine tundra, which occurs at high altitude, and arctic tundra, which is in or near the Arctic Circle.
- A desert gets less than ten inches of rain every year, so its plants have long roots, small leaves, and stems that can store water.
- An ice sheet is an area where a glacier covers the land for more than 20,000 miles, leading to no vegetation. There are only two ice sheets in the world: in Antarctica and in Greenland.
Find out how well you can complete these actions when the lesson ends:
- State the meaning of ‘vegetation region’
- Remember the five different vegetation regions on earth
- Compare deciduous and evergreen forests
- Name the two types of grasslands and the two types of tundras
- List the characteristics of deserts and ice sheets