Lesson Two - Ecosystems | Earthwatch Australia Teach Live

Lesson Two - Ecosystems

In this lesson you will:

Learn what an ecosystem is
Learn components of the tropical rainforest ecosystem

ECOSYSTEMS

The BIOSPHERE describes our living world. It is where all of the plants, insects and animals live. The biosphere extends to the upper limits of the atmosphere (what were the four layers again?), to the depths of the hydrosphere, to the underground caves of the lithosphere.

The biosphere can be thought of as an interaction between the hydrosphere, lithosphere and atmosphere. All of the forces in each sphere work together to create our living world. Since the biosphere is so large and all-encompassing, and it’s relationships so complex, we normally study smaller components of the biosphere called ecosystems.

Introductory Questions:
1. Define in detail; atmosphere, lithosphere and hydrosphere.
2. Think of four species that live in each sphere.
3. Define the term ecosystem

TROPICAL RAINFORESTS

Tropical rainforests cover about 1000 million hectares of the world. Although only about 8% of the planet’s land area, they are home to more than 13 million different plants and animals – that’s over half the world’s total number of species.

Tropical rainforests only exist between the Tropic of Capricorn and the Tropic of Cancer. The Tropic of Cancer and the Tropic of Capricorn are two major circles of latitude that can be found on maps of the earth. The Tropic of Cancer is found in the northern hemisphere while the Tropic of Capricorn can be found in the southern hemisphere.

Australia’s tropical rainforests make up about only about 0.001% of the world’s tropical rainforests and cover only 0.2% of the Australian continent.