Wednesday, March 11, 2009

Biomes and Biodiversity

The six major biomes on Earth are rain forest, desert, grassland, deciduous forest, boreal forest and tundra. It is mostly the climate in an area that determines its biome.

Rain Forests- Tropical rain forests are warm and humid and found near the equator. The abundant plant life in tropical rain forests provides habitats for many species of animals

Deserts- A desert is an area that receives less than 25 centimeters of rain each year. Desert organisms are adapted to lack of rain and extreme temperatures.

Grasslands- Most grasslands receive between 25 and 75 centimeters of rain each year. Grasslands do not get enough rain to support trees.

Deciduous Forests - The trees found in deciduous frests shed their leaves and grow new ones each year. These forests receive at least 50 centimeters of rain each year.

Boreal Forests - Boreal forests contain coniferous trees, which produce their seeds in cones and have leaves shaped like needles. Winters in boreal forests are long, cold, and snowy.

Tundra - The tundra is extremely cold and dry. Most of the soil is frozen all year long.

Aquatic Ecosystems - Freshwater ecosytems include streams, rivers, ponds, and lakes, while oceans, seas, and some marshes make up saltwater ecosytems. An estuary is found where the fresh water of a river meets the salt water of the ocean . Between the highest high-tide lien and the lowest low tide line is the intertidal zone. The aquatic ecosystems are home to more organisms on Earth than any other ecosystem.