BIOMESChapters 6 & 7

Biomes

• Are usually DESCRIBED by their vegetation

• Precipitation is the MAIN factor that determines what type of plants grow in a biome

• Plants have specific ADAPTATIONS which help them survive in their biome

• With high temps & low precipitation (like deserts) have short, less dense vegetation

Biomes From North to South

• Tundra

• Taiga

• Grassland

• TropicalRainforest

African Savannah

•Here you are most likely to see large herds of grazing animals such as rhinos, gazelles, & giraffes.

Grasslands

• Grasslands have the most fertile soil in the world & are suitable for crops such as wheat, corn, & soybeans

• Receive between 10 & 35 inches of rain per year; not enough to support trees

• Even though the buffalo population is not as large as it once was, prairies still support them as well as badgers, prairie dogs, & burrowing owls

Grasslands are threatened by soil erosion because native grasses have been damaged or destroyed by plowing or overgrazing

Deserts

• Are the driest places on Earth getting less than 25 cm (10 in) of rainfall per year.

• Contain a variety of plant life including cacti & succulents except in the most extreme conditions

• Many kinds of deserts, including cold deserts, are located throughout the world

• Are often located on the dry side of mountain ranges

Desert Animals

• Are small to moderate in size

• Examples: Gila monsters, rattlesnakes, spiders, elf owls

• Reptiles have thick scaly skin that prevents water loss

• Amphibians Estivate – bury themselves underground & sleep through the dry season

• Nocturnal – mainly active at night or dusk when air is cooler

Tundra

• Permafrost – a layer of soil that is permanently frozen throughout the year

• Insects are especially abundant here during the summer season

• Is one of the most fragile biomes on the planet

• Simple food chains mean that they are easily disrupted

Tundra Animals

• Rodents such as lemmings, mice, & hares burrow underground during the winter

• These animals do not hibernate, but instead are active in their underground winter homes

Tundra Animals

• Arctic foxes & hares grow white fur in the winter to help them blend with their habitat

• Caribou migrate in search of food & water

Taiga

• Stretches across the northern hemisphere just below the arctic circle

• Consists mostly of coniferous forests consisting of pine, fir, & spruce

Taiga Vegetation

• Thrives in the acidic soil that is found there

• Have leaves that retain water due to their needle-like shape & waxy coating.

• The umbrella-like shape of the trees helps snow roll off them so that branches do not break

Tropical Rain Forests Are Threatened By…

• Deforestation – cutting down & clearing large areas of forest

• Legal AND Illegal trade of plants & animals

Tropical Rainforest Vegetation

• Include trees with above-ground roots called buttresses which increase stability in thin soil

Tropical Rainforest Vegetation• Orchids &

vines grow on tree trunks rather than from the ground

Tropical Rainforest Vegetation

• Herbs & ferns with large flat leaves thrive in the understory

Tropical Rainforest Destruction

• Can result in climate change & flooding

Chaparral Vegetation• Survive fires because they can

resprout from small amounts of surviving plant tissue

Name the Biome?

You are walking through a humid forest that gets abundant rain. However, temperatures are moderate.

Name the Biome?

You are walking through a humid forest that gets abundant rain. However, temperatures are moderate.

The Pacific Northwest - Temperate Rain Forest

Name the Biome?

Forest with the greatest species diversity; located near the equator.

Name the Biome?

Forest with the greatest species diversity; located near the equator.

Tropical Rain Forest

What Do Wetlands Do?

•Decrease runoff•Absorb & remove pollutants from water•Control flooding•Provide animal habitats

What are Estuaries?

•An estuary is a body of water formedwhere freshwater from a river meets the saltwater from an ocean•Estuaries are important, nutrient-rich ecosystems

What are the Main Threats to Ocean Ecosystems?

• Nutrient runoff

• Industrial waste discharges

• Overfishing

• Entanglement of marine mammals in trawl nets

• Sewage

• Algae blooms

What Factors Determine What Organisms Can Live in a Lake or Pond?

• Amount of Sunlight

• Water Temperature

• Nutrient Levels

Where Does Most Ocean Pollution Come From?

• Activities that take place on land.

• In fact, most coastal pollution is the result of industrail waste & sewage.

How do Many Rivers Start?

• Mountain Snowmelt