Biomes

KEY CONCEPT Biomes are land-based, global communities of organisms.

Biomes

Earth has several major biomes.

• A biome is a major community of organisms.

Biomes

• Tropical rain forest biomes produce lush forests.– warm temperature– abundant

precipitation all year

Source: World Meteorological Organization

Biomes

• Grassland biomes are where the primary plant life is grass.

Rapid City, South Dakota

Source: National Oceanic Atmospheric Administration

Biomes

– Temperate grasslands are dry and warm during the summer; most precipitation falls as snow.

• Grassland biomes are where the primary plant life is grass.

– Tropical grasslands are warm through the year, with definite dry and rainy seasons.

Biomes

• Desert biomes are characterized by a very arid climate.– very low amount of

precipitation– four types: hot, semi-

arid, coastal, and cold

Tucson, Arizona

Source: National Oceanic Atmospheric Administration

Biomes

• Temperate forest biomes include deciduous forests and rain forests.– Temperate deciduous forests have hot summers and

cold winters.– Deciduous trees are the dominant plant species.

Source: National Oceanic Atmospheric Administration

Burlington, Vermont

Biomes

– Deciduous trees are the dominant plant species.– The temperate rain forests have a long wet season and

relatively dry summer.

• Temperate forest biomes include deciduous forests and rain forests.– Temperate deciduous forests have hot summers and

cold winters.

– Ferns and moss cover the forest floor. 

Biomes

• The taiga biome is located in cooler northern climates.– boreal forest– long winters and short

summers– small amount of

precipitationSource: Environment Canada

Banff, Canada

Biomes

• The tundra biome is found in the far northern latitudes with long winters.– winter lasts 10 months– limited precipitation– permafrost

Barrow, Alaska

Source: National Oceanic Atmospheric Administration

Biomes

• Minor biomes, such as chaparral, occur globally on a smaller scale.

Biomes

Polar ice caps and mountains are not considered biomes.

• Polar ice caps have no soil, therefore no plant community. • The climate and organisms found on mountains change as

the elevation changes.

Marine Ecosystems

KEY CONCEPT Marine ecosystems are global.

Marine Ecosystems

– neritic zone—from intertidal zone to continental shelf

– bathyal zone—from neritic zone to base of continental shelf

– abyssal zone –lies below 2000 m

The ocean can be divided into zones.

• Ocean zones can be determined by their distance from shoreline and water depths.– intertidal zone—between low and high tide

intertidal zoneneritic zone

bathmatzone

abyssalzone

Marine Ecosystems

• The neritic zone harbors more biomass than any other zone.

• Plankton make up most of the biomass.– zooplankton– phytoplankton

Marine Ecosystems

Coastal waters contain unique habitats.

• Coral reefs are found in warm waters.– tropical climate zone– great amount of biomass

Marine Ecosystems

• Kelp forests are found in cold, nutrient-rich waters. – large communities of

seaweed– great amount of

biomass

Estuaries and Freshwater Ecosystems

KEY CONCEPT Freshwater ecosystems include estuaries as well as flowing and standing water.

Estuaries and Freshwater Ecosystems

Estuaries are dynamic environments where rivers flow into the ocean.

• An estuary is a partially enclosed body of water.– mixture of fresh water with salt water– Chesapeake Bay– Louisiana bayous

Estuaries and Freshwater Ecosystems

• Estuaries are highly productive ecosystems.

• Estuaries provide a protected refuge for many species.– birds migration– spawning grounds

• Estuaries are primarily threatened by land development.

Estuaries and Freshwater Ecosystems

Freshwater ecosystems include moving and standing water.

• A watershed is a region of land that drains into a body of water.

• Ecosystems may be different along a river’s course

Estuaries and Freshwater Ecosystems

• Wetlands are among the most productive ecosystems.– provide a home for many species– filter dirty water– renew underground water supply

• Some animals have adaptations suited to the freshwater they inhabit.

Estuaries and Freshwater Ecosystems

Ponds and lakes share common features.

• Freshwater bodies are divided into three zones.– littoral zone– limnetic zone– benthic zone

Estuaries and Freshwater Ecosystems

• All lakes “turn over” periodically.– Turn over happens due to changes in density.– In both autumn and spring, surface water flows

downward and bottom water flows upward.– The upwelling brings up nutrients.