Chapter 6 - Biomes

Biomes A biome is a large region characterized by a specific type of climate and certain types of plant and animal communities. Biomes are described by plant life because they determine what other organisms live there. The plant life found in a biome is determined by temperature and rainfall.

Biomes of the World

Biomes Climate plays a huge role in what organisms develop. Temperature and Precipitation are the two main factors.

Biomes Latitude and Altitude also play an important role in climate. Latitude = distance from equator. Altitude = height above sea level.

Forest Biomes Tropical Rainforest Located near the equator and characterized by average temperatures of 25o C (77o F) rainfall 200-450 cm per year. Has poor soil quality due to heavy leaching of soil by water. Contains more biodiversity than any other land biome including up to 50 % of the world’s species. Many of mankind’s medicines originated in the tropical rainforest.

Layers of the Rainforest Emergent Layer Upper Canopy Lower Canopy Understory

Forest Biomes (cont.) Threats to the tropical rainforest include: Deforestation/Habitat Destruction/Loss of Biodiversity

Forest Biomes (cont.) Temperate Forests Temperate Deciduous Forest Temperate Rainforest

Forest Biomes (cont.) Temperate Rainforest in North America in the Northwest Pacific Coast Characterized by moist climate, evergreen trees and lush ferns covering forest floor

Forest Biomes (cont.) Temperate Deciduous Forest located between 30o and 50o North Latitude temperature ranges from below 0o to 35oC (32o – 95oF) characterized by distinctive seasons plants adapt by shedding leaves in winter

Forest Biomes (cont.) Taiga also called boreal forest temperature ranges from -10o C to 20o C (14o – 68o F) plants have modified leaves, triangle shape, and natural resin “antifreeze” (Conifers) animals adapt in many ways including camouflage and hibernation

Forest Biomes (cont.) The greatest threat to temperate forests is Deforestation

Grasslands Tropical Savanna found between deserts and tropical rainforests

Grasslands Tropical Savanna found between deserts and tropical rainforests temperature is ranges between 20o -30o C (68o- 86o F) characterized by 2 distinctive seasons – wet and dry

Grasslands (cont.) Tropical Savanna – Plant adaptations Grasses have extensive horizontal root systems to obtain as much water as possible and combat fires. Grass leaves have limited surface area exposed to the sun Trees conserve water by storing it in trunks (Boabab tree) or shedding leaves in the dry season Some trees (Acacia tree) and shrubs have thorns to combat herbivores

Grasslands (cont.) Tropical Savanna – Animal adaptations Vertical feeding patterns means different organisms feed at different levels For example : Zebra and Giraffe

Grasslands (cont.) Tropical Savanna – Animal adaptations Vertical feeding patterns means different organisms feed at different levels For example : Zebra and Giraffe Large herds of herbivores migrate to follow precipitation patterns and only give birth once a year

Grasslands (cont.) Temperate Grasslands found in the interior of continents and have little rainfall characterized by very cold winters and warm summers

Grasslands (cont.) Temperate Grasslands - includes Prairies in North America Steppes of Mongolia or Ukraine Pampas of South America

Grasslands (cont.) Temperate Grasslands – Plant Adaptations dominated by grasses, virtually no trees due to lack of rainfall, wind, and fires dense root systems hold very fertile soil in place Height of plants depends upon amount of rainfall – shortgrass (25cm), mixed grass (50cm), tallgrass (88cm)

Grasslands (cont.) Temperate Grasslands – Animal Adaptations some animals burrow underground to escape predators, fire, or harsh weather herbivores have teeth for grazing and coats for winter that shed in summer

Grasslands (cont.) Temperate Grasslands – Threats Overgrazing cattle can lead to desertification Poor farming practices can lead to soil erosion

Grasslands (cont.) Chaparal – characterized by broad-leafed evergreen shrubs warm, dry summers/ mild ,wet winters plants have leathery leaves to retain water For example: Sage These plants also contain oils that promote burning plants are very adapted to fire

Grasslands (cont.) Chaparal – characterized by broad-leafed evergreen shrubs warm, dry summers/ mild ,wet winters plants have leathery leaves to retain water animals are usually colored to be camouflaged within the biome

Grasslands (cont.) Chaparal – characterized by broad-leafed evergreen shrubs warm, dry summers/ mild ,wet winters plants have leathery leaves to retain water animals are usually colored to be camouflaged within the biome Greatest threat to chaparral is development by humans

Deserts receive less than 25 cm of precipitation per year deserts have extreme temperatures

Deserts receive less than 25 cm of precipitation per year deserts have extreme temperatures deserts range from no vegetation to varied vegetation Some are hot like the Sahara Some are cold like the Gobi

Deserts Plants called succulents are adapted for life in the desert waxy coating to prevent water loss folds to capture water and facilitate expansion root systems that use a long tap root as well as multiple shallow spreading roots many desert plants have thorns or spines to prevent herbivores from eating them

Deserts Animals most are nocturnal functioning at night when its cooler reptiles have thick scaly skin to prevent water loss some move in ways that combat heat

Deserts Animals Some animals estivate to avoid heat and drought Some mammals have exteme ways of cooling down

Rain Shadow Effect Process that creates deserts on the eastern side of mountains

Tundra

Tundra Receives very little precipitation. Precipitation is usually in the form of snow. Has layer of soil that is permanently frozen called permafrost.

Tundra Is characterized by two distinct seasons long winters in which the biome is covered in snow

Tundra Is characterized by two distinct seasons short summers in which the biome vegetation blooms and the landscape is covered in bogs and swamps (which are breeding grounds for insects)

Tundra Plant adaptations include growing close to the ground to avoid wind and absorb heat from soil wide shallow roots to help anchor in the thin soil

Tundra Animal adaptations include burrowing during winter months camouflage to blend into snow in winter

Tundra Animal adaptations include burrowing during winter months camouflage to blend into snow in winter Migration of birds and large herds of grazing mammals Large reserves of fat

Tundra Threats to biome include global warming causing melting of vast regions of permafrost

Tundra Threats to biome include global warming causing melting of vast regions of permafrost oil pipelines may disrupt migration patterns or cause spills very fragile ecosystem that takes many years to recover from any change or damage