Facts At Your Fingertips: The living world – Ecosystems
A community of organisms that lives in a particular environment is called an ecosystem. A single ecosystem might be as small as a pond or as large as a desert.
Ecosystems vary hugely across the world, depending on conditions such as climate, the soil type, or whether there is salt- or freshwater.
NORTH AMERICA
Tundra is found near polar regions and high up on mountains, where it is too cold for trees and so only small flowers and grasses grow.
It covers one-fifth of the Earth’s land.
Grasslands are wide areas that are baked brown by the Sun in summer and may freeze over in the winter. They are covered with grasses and have few trees.
SOUTH AMERICA
Rain forests have a thick covering of trees and a rich variety of animal life.
Mountains are high places with a cold, windy climate.
Very different groups of plant and animal are found at different heights, as the climate changes rapidly between the peaks and the valleys.
EUROPE
Polar regions are harsh areas near the North and South poles, where it is cold all year round. Snow and ice cover the ground and plant life is scarce.
ASIA
Wetlands are areas of land that are flooded with water, such as swamps, marshes, and bogs. Plants adapted to wet conditions grow here.
Coniferous forests are the largest forests in the world and mostly contain conifer trees with needlelike leaves. They are found in cold, northern regions.
Most trees in temperate forests grow new leaves every spring and drop them every fall to save energy during the cold winter.
AFRICA
Deserts are dry places where there is little or no rain. Only plants and animals that are specially adapted to the lack of water can live here.
AUSTRALIA
Oceans cover almost three-quarters of the Earth’s surface. They have a rich variety of life, most of which is found in the layers near the surface.
TEEMING WITH LIFE
Coral reefs found in shallow, tropical waters are some of the most diverse habitats on Earth. Although they cover just 0.1 percent of the oceans, they are home to 25 percent of ocean species, including mollusks, sea snakes, crustaceans, and many kinds of colorful fish.
The Great Barrier Reef is 1,600 miles (2,600 km) long and is so large that it can be seen from space