Earth’s Major Biomes o Biome A large, relatively distinct terrestrial region with a similar climate soil, plants, and animals. A large, relatively distinct terrestrial region with a similar climate soil, plants, and animals. Nine major biomes Nine major biomes o Location of each biome is primarily determined by: Temperature (varies with both latitude and elevation) Temperature (varies with both latitude and elevation) Precipitation Precipitation o Biomes can also be defined by Winds, rapid temperature changes, fires, floods, etc. Winds, rapid temperature changes, fires, floods, etc.

Earth's Major Biomes o Earth’s Major Biomes Tundra, Boreal Forests, Temperate Rainforest, Temperate Deciduous Forests, Grasslands, Chaparral, Deserts, Savanna, & Tropical Rainforests Tundra, Boreal Forests, Temperate Rainforest, Temperate Deciduous Forests, Grasslands, Chaparral, Deserts, Savanna, & Tropical Rainforests Vertical Zonation Vertical Zonation o Aquatic Ecosystems Freshwater ecosystems Freshwater ecosystems Estuaries Estuaries o Marine Ecosystems o Interaction of Life Zones and Humans

Vertical Zonation o Increasing in elevation has similar effect on ecosystem as traveling to higher latitudes

Tundra o Treeless biome in the far north with harsh, cold winters and extremely short summers o Precipitation cm/yr cm/yr o Temperature Short growing season Short growing season days days

Tundra o Nutrient poor soils with little organic material Permafrost present Permafrost present o Low species richness Veg is mostly grasses and sedges Veg is mostly grasses and sedges Very simple food web Very simple food web o Low primary productivity

Boreal Forests o A region of coniferous forests in the northern hemisphere Just south of tundra Just south of tundra o Covers 11% of earth’s land land o Growing Season A little longer than A little longer than tundra tundra o Precipitation ~ 50 cm/yr ~ 50 cm/yr

Boreal Forests o Soils are acidic and mineral poor o Vegetation comprised of drought resistant conifers White spruce White spruce Balsam fir Balsam fir Eastern larch Eastern larch o Mostly small animals and migrating birds o Some large animals are present Wolves, bear, moose Wolves, bear, moose

Temperate Rainforest o Coniferous biome with cool weather, dense fog and high precipitation Ex: Northwest US Ex: Northwest US o Precipitation > 127 cm/yr > 127 cm/yr Heaviest in winter Heaviest in winter o Temperature Winters are mild Winters are mild Summers are cool Summers are cool

Temperate Rainforest o Soils are nutrient-poor, but high in organic material (dropped needles) Cool temperatures slow decomposition Cool temperatures slow decomposition o Dominant Vegetation Large evergreen trees Large evergreen trees Old-growth forest Old-growth forest o Variety of cool climate animal life climate animal life o Very high species richness richness

Temperature Deciduous Forests o Forest biome that occurs in temperate areas with a moderate amount of precipitation o Precipitation cm/yr cm/yr o Temperature Seasonality Seasonality Hot summers and cold winters Hot summers and cold winters

Temperate Deciduous Forest o Topsoil is rich in organic material and underlain by clay o Vegetation is primarily deciduous Oak, maple, beech Oak, maple, beech o Animals Deer, bear and small animals Deer, bear and small animals

Grassland o Grasslands with hot summers, cold winters and too little precipitation to support trees o Precipitation cm/yr cm/yr o Tall grass prairies o Short grass prairies o 90% of this biome has been lost to farmland

Grassland o Soil has thick, organic material rich organic horizon. o Periodic fires keep the dominant vegetation grasses grasses o Animals Once covered with bison- no longer true Once covered with bison- no longer true Smaller animals are still present (ex: prairie dogs) Smaller animals are still present (ex: prairie dogs)

Chaparral o Also called a Mediterranean Climate Ex: Southern California Ex: Southern California Ex: Greece Ex: Greece o Temperature Mild, moist winters Mild, moist winters Hot, dry summers Hot, dry summers o Frequent fires

Chaparral o Soil is thin and often not fertile o Vegetation Dense growth of evergreen shrubs Dense growth of evergreen shrubs Lush during the growing season Lush during the growing season o Animals Mule deer, chipmunks, many species of birds Mule deer, chipmunks, many species of birds

Deserts o Biome where lack of precipitation limits plant growth o Temperature Can vary greatly in 24-hr period, as well as yearly (based on location) Can vary greatly in 24-hr period, as well as yearly (based on location) o Precipitation < 25 cm/yr < 25 cm/yr

Deserts o Soils low in nutrients, high in salts o Vegetation sparse cactus and sagebrush cactus and sagebrush o Animals are very small to regulate temperature Sonoran Desert

Savanna o Tropical grassland with widely scattered trees o Temperature Varies little throughout the year Varies little throughout the year o Precipitation Seasons regulated by precipitation, not temperature Seasons regulated by precipitation, not temperature cm/yr cm/yr

Savanna o Soil low in nutrients o Vegetation Wide expanses of grass Wide expanses of grass Occasional Acacia trees Occasional Acacia trees o Animals Herds of hoofed animals Herds of hoofed animals Large predators- lions, hyenas, etc. Large predators- lions, hyenas, etc.

Tropical Rainforest o Lush, species-rich biome that occurs where climate is warm and moist throughout the year o Precipitation cm/yr cm/yr o Very productive biome o Most species-rich biome

Tropical Rainforest o Ancient, weathered, nutrient- poor soil Nutrients tied up in vegetation, not soil Nutrients tied up in vegetation, not soil o Vegetation Richest and thickest on earth Richest and thickest on earth o Animals Most abundant insect, reptiles and amphibians on earth Most abundant insect, reptiles and amphibians on earth

Rivers and Streams o Changes greatly from headwater to mouth o Headwaters Shallow, cool, swiftly flowing, high oxygenated Shallow, cool, swiftly flowing, high oxygenated o Mouth Not as cool, slower flowing, less oxygen in water Not as cool, slower flowing, less oxygen in water

Lakes and Ponds o Littoral Zone - shallow water area along the shore o Limnetic Zone - open water beyond the littoral zone o Profundal Zone - beneath the limnetic zone of deep lakes

Marshes and Swamps o Lands that shallow, fresh water covers for at least part of the year Characteristic soil- water logged and anaerobic for periods of time Characteristic soil- water logged and anaerobic for periods of time Water tolerant vegetation Water tolerant vegetation o Were once regularly filled in More recently their ecosystem services have been better recognized More recently their ecosystem services have been better recognized Flood protection, water Flood protection, water filtering, etc.

Estuaries o Where freshwater and saltwater mix o Highly variable environment Temperature, salinity, depth of light penetration Temperature, salinity, depth of light penetration o Highly productive Nutrients transported from land Nutrients transported from land rapid circulation of nutrients rapid circulation of nutrients

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