1. Biomes of the World
5.1

2. What is a Biome?
-The earth has many ecosystems -Scientists group ecosystems into larger areas called Biomes -There are two main categories of Biomes: -Terrestrial (land) -Aquatic (water)

3. Terrestrial Biomes The Earth has 10 major land biomes:
Tropical Rain Forests
Deciduous Forests
Coniferous Forests
Temperate Grasslands
Savannas
Chaparral
Deserts
Tundra
Mountains
Polar Ice

4. Terrestrial Biomes Each biome is characterized by a particular climate
What makes the climate?
Average annual temperatures
Amounts of precipitation
Both help to determine the types of plants that can grow there
The plants, in turn, help determine what types of animals can live in each biome

5. Diversity in Biomes
The total diversity of biomes is determined largely by the amount of precipitation and average temperature
Living things need water to survive
The desert and tundra biomes both get very little precipitation, therefore have less diversity
Rainforests get a lot of rain and have hot, humid temperatures
This makes the rain forests the most diverse ecosystems on Earth

6. Location Biomes located closer to the equator have higher temperatures
Biomes are divided by latitude and location
Polar Zone – farthest from equator
Temperate Zone – Warmer than the polar zone
Tropical Zone – Closest to equator
As the latitude increases, the temperature decreases

7. Aquatic Biomes Make up more than 70% of the Earth’s surface
Aquatic biomes are not grouped by climate
They are grouped by water depth and salinity
Salinity is the amount of salt dissolved in the water
Rainfall and temperature also affect aquatic biomes
2 main groups of Aquatic biomes
Freshwater
Saltwater

8. Aquatic Types Freshwater Rivers Streams Ponds Lakes Swamps Saltwater
Oceans
Estuaries
Coral Reefs
Saltwater Marshes

9. Salinity All biomes contain some dissolved salt and other minerals
However, oceans contain more dissolved salt than the water found in freshwater systems
This salinity is measured in parts per thousand
The salinity of ocean water is about 30 parts per thousand
The salinity of freshwater biomes is about 0.5 parts per thousand or less

10. Depth
The depth of water also determines what kinds of organisms can survive there
In areas where sunlight can reach, more organisms can live there
Aquatic plants use sunlight to create food
As sunlight decreases with depth, the plant and animal life decreases
In the deep ocean, the water is too dark for photosynthesis

11. Scientists and Biomes
Scientists study biomes to learn more about how organisms survive in different habitats
They investigate how organisms have adapted to temperature, rainfall, water depth, and salinity
They also study how land biomes affect aquatic biomes
Biomes are fragile and need protected

12. Vocabulary
Biome
Terrestrial
Aquatic
Salinity
Saltwater
Freshwater