Tropical grasslands are called savannas. Savannas exist in places that are warm throughout the year. They often have scattered trees. Savannas such as the Serengeti plains stretch across much of central Africa. Not all plains are grasslands. Forested plains have different types of trees, shrubs, and other vegetation. Deserts can also be plains. Parts of the Sahara, a great desert in North Africa, are plains. In the Arctic , where the ground is frozen, plains are called tundra.
Despite the cold, many plants survive here, including shrubs and moss. Plain Formation Plains form in many different ways. Some plains form as ice and water erodes, or wears away, the dirt and rock on higher land.
Water and ice carry the bits of dirt, rock, and other material, called sediment , down hillsides to be deposited elsewhere. As layer upon layer of this sediment is laid down, plains form.
Volcanic activity can also form plains. Lava plains form when lava pushes up from below ground and flows across the land. The earth in a lava plain is often much darker than the surrounding soil.
The dark earth is a result of the lava, mostly a dark-colored mineral called basalt , broken down into tiny particles over millions of years. The earth in a lava plain is often much darker than the surrounding soil. The dark earth is a result of the lava, mostly a dark-colored mineral called basalt , broken down into tiny particles over millions of years. The movement of rivers sometimes forms plains. Many rivers run through valleys. As rivers move from side to side, they gradually erode the valley , creating broad plains.
As a river floods, it overflows its bank. The flood carries mud , sand , and other sediment out over the land. After the water withdraws, the sediment remains.
If a river floods repeatedly, over time this sediment will build up into a flood plain. Flood plains are often rich in nutrients and create fertile farmland. Alluvial plains form at the base of mountains. Water carrying sediment flows downhill until it hits flat land. There, it spreads out, depositing the sediment in the shape of a fan. The Huang He River in China has created an alluvial plain that covers about , square kilometers , square miles.
Because much of the sediment the Huang He carries is yellowish in color, it is also called the Yellow River. Many rivers deposit their sediment in the ocean. As the sediment builds up, it might eventually rise above sea level , forming a coastal plain.
These broad underwater plains slope gently down beneath the water. Abyssal plains are found at the bottom of the ocean. These plains are 5, to 7, meters 16, to 23, feet below sea level, so scientists have a hard time studying them. But scientists say abyssal plains are among the flattest, smoothest places on Earth.
Thundering Hooves The Great Plains of North America once supported about 50 million bison, which are sometimes called buffalo. The bison roamed in vast herds, feeding on the prairie grasses. They were hunted to near-extinction in the s. Plains on Other Planets Plains can be found on other planets. Mercury has large stretches of plains, and scientists have landed several probes on the boulder-covered plains of Mars. Regions are the basic units of geography. Sea level is determined by measurements taken over a year cycle.
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They will best know the preferred format. When you reach out to them, you will need the page title, URL, and the date you accessed the resource. The vast grasslands full of thick grasses and rich soil make this region perfect for farming and grazing. The Central Plains region is mostly rural grasslands and small towns with a few large cities. Most of this prairie land is thick grasses. There is also a cross timbers area full of hardwood trees. Farming is common here because of the fertile soil.
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