Ecosystem Balance

E5 Land Biomes

Land Biomes• The movement of matter and flow of energy

are common to all ecosystems• But, differences in temperature and rainfall

create a vast array of conditions• Life has adapted to almost all of these

environments.

Types of Biomes• The ecosystems of Earth can be divided into

several broad categories• Biome – A major type of ecosystem with

distinctive temperature, rainfall, and organism

Land Biomes• A biome is the largest category scientists use

to classify ecosystems.• Because it is so large, conditions in a biome

may vary from place to place• There are many different ecosystems within

a biome with different habitats, conditions, and organisms.

Land Biomes

• On land, the type of biome in a given area depends on the average temperature and amount of precipitation the area receives

• In water, the type of biome is determined by water depth, nutrients, and nearness to land

• Biomes are either terrestrial (on land) or aquatic (in water)

Terrestrial Biomes• Earth can be divided into 9 major biomes

Land Biomes• Desert and Tundra Biomes

• Both receive very little water

• Biomass is the total mass of organic material in an ecosystem

• Deserts covers 25% of Earth's land surface but contain only 1% of it's biomass.

• Both support only a small amount of biomass

• Lack of water makes plant life scarce

• Two different biomes, but…

• Limits the amount of organisms it can support

• Forest Biomes - contain 75% of Earth's biomass• There are three forest biomes

1. Coniferous Forests

• Very long, very cold, snowy winters• Warm, humid summers• Well-defined seasons• Four to six frost-free months

• Locations: Canada, Europe, Asia, and Western United States

Land Biomes2. Deciduous Forests

• Cold, snowy winters• Warm, humid summers• Well-defined seasons• Six – eight frost-free months

• Locations: Eastern United States, Canada, Europe, China, and Japan

Land Biomes3. Rain Forests• Receive abundant precipitation.

• Covers only 6% of Earth's land surface, but contains more than 50% all biomass.

• Most diverse biome

• Locations: Tropical Regions between the Tropic of Cancer and the Tropic of Capricorn

Land Biomes

• In some parts of the tropics, a rainy season is followed by a dry season

• Tropical Dry Forest Biomes

• During the dry season, nearly all the trees drop their leaves to conserve water

• Warm year-round• Abundant rain in wet season• Long dry season

• Locations: Africa, South and Central America, Mexico, India, Australia

Land Biomes

• Precipitation is highly seasonal• Woodland and Shrubland Biome

• During the dry season, nearly all the trees drop their leaves to conserve water

• Hot, dry summers• Cool, rainy winters.

• Locations: California, Chile, South Africa, Southwestern Australia, and bordering the Mediterranean Sea.

• Biome occurs on west-facing edges of continents.

Land Biomes

• Made up of densely growing, low plants that contain flammable oils.

• The Chaparral Biomes

• Some are woody evergreen shrubs with small, leathery leaves

• Others are fragrant oily herbs that grow during winter and die in summer.

• Fire plays an important part in maintaining the ecosystems in this biome

Land Biomes• Plants catch fire easily during the dry season• Are adapted to recurrent fires• Some grow back quickly• Others have seeds that must be exposed

to fire in order to germinate.

• Locations: Western parts of United States, South America, Africa, Australia, and Mediterranean

Land Biomes• Some land areas cannot easily be classified as

belonging to a particular biome.• Example: High Mountains • Lower temperatures and receive more

precipitation than surrounding areas• Plants and animals found in mountains

can be quite different from those in nearby lowlands.

Section Review• Answer the questions in the section review