CHAPTER 3: CHAPTER 3: COMMUNITIES + BIOMESCOMMUNITIES + BIOMES

Section 3-2: BiomesSection 3-2: Biomes

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What is a Biome?What is a Biome?• A large group of ecosystems that share

the same type of climax community

• Two Types:– Terrestrial– Aquatic

Aquatic BiomesAquatic Biomes• Marine

– AKA: Oceans or saltwater– Abiotic factors:

• Salinity• Depth• Light• Temperature

Parts of the OceanParts of the Ocean• Photic zone

– Portion of the marine biome that is shallow enough for light to penetrate

– Examples:• Bays• Rocky shores• Sandy beaches• Coral reefs

Parts of the OceanParts of the Ocean

• Aphotic zone– Deeper water that never receives sunlight

Ocean ZonesOcean Zones

EstuariesEstuaries• Coastal body of water,

partially surrounded by land, in which freshwater and salt water mix

– River ‘meets’ ocean– Can differ in amount of

salinitysalinity (salt) compared to seawater + freshwater

TidesTides• Caused by the gravitational pull of sun +

moon

Effects of TidesEffects of Tides• Intertidal zoneIntertidal zone

– Portion of the shoreline that lies between high and low tide lines

Effects of TidesEffects of Tides– Size

• Varies due to slope of land + difference between high + low tide

– High Levels of sunlight, nutrients, + oxygen– Zones differ in rockiness + wave action

In the LightIn the Light

• The further out in the ocean, the less effect waves or tides have on the ecosystem

• The photicphotic zone has abundant life + high productivity

In the LightIn the Light• PlanktonPlankton

– Small organisms that drift + float in the waters of the photic zone

– Includes:• Autotrophs• Diatoms• Juvenile animals

– Makes up the base of all aquatic food chains

Aquatic Food Chain/WebAquatic Food Chain/Web

In the DarkIn the Dark• Many animals living in the deeper parts

of the ocean still depend upon planktonplankton for food

Freshwater BiomeFreshwater Biome

• Includes:– Lakes– Ponds– Streams– Rivers

Freshwater BiomeFreshwater Biome• Limiting Factors:

– Temperature– Light

Other Aquatic Biomes - Other Aquatic Biomes - WETLANDSWETLANDS

• Swamps– Have trees

• Marshes– Found

inland/coastal– Water flows– Food sources for

migratory birds

• Bogs– Gets water from rain

Terrestrial BiomesTerrestrial Biomes

LatitudeLatitude

• Describes your position in degrees north and south of the equator

• At different latitudes, the sun strikes the Earth differently.

• As a result, the climates are different– EX: Wind, cloud cover, temperature, humidity

• These are both abiotic factors that affect what plants + animals will survive in a given area

ClimatographsClimatographs

Life on the TundraLife on the Tundra• Location

– Area that circles the north pole• Description

– Treeless land with long summer days and short periods of winter sunlight

• Temperature– Yearly = 10 – 20 o F

• Permafrost– Top layer of ground that is

permanently frozen• Soil

– Very thin but can support shallow-rooted grasses + plants

• Climate– Windy– Long summer days– Short growing season– Less than 10” rain/year

Life on the TundraLife on the Tundra

• Plants

• Animals

Cushion plant

Dwarf shrub

Life on the TaigaLife on the Taiga• Location

– South of the tundra– Also known as Boreal or Coniferous

forest

• Description– Continuous belt of coniferous trees

(larch, fir, hemlock, + spruce)• Temperature

– Warmer + wetter than tundra

• Climate– Harsh– Long, severe winters + short, mild

summers

• Soil– Topsoil is acidic + poor in minerals– Has more trees than tundra

Life on the TaigaLife on the Taiga• Plants

• AnimalsSpruce

Hemlock

Life in the DesertLife in the Desert• Location

– Mid to southern latitudes

• Description– Arid region with almost nonexistent

plant life• Temperature

– Hot during day– Cold at night

• Rainfall– Less than 25 cm/year

• Adaptations– Plants

• Thick stems• Spines• Poisons

– Animals• Underground during day, out

at night

Life in the DesertLife in the Desert• Plants

• Animals

creosote

Life in the GrasslandLife in the Grassland• Location

– Mid to southern latitudes

• Description– Large communities covered

with rich soil, grasses, + similar plants

• Temperature– Wet/humid or Hot/cold

• Rainfall– 25-75 cm/year

• Soil– Rich in humus– Sodded areas, few trees

• “Breadbaskets”– Ideal for growing cereal grains

Life in the GrasslandLife in the Grassland• Plants

• Animals

sunflowers

Blazing starsoats

Life in the GrasslandLife in the Grassland• Other names for Grasslands

– Prairie– Steppes– Savannas– Pampas

Life in Temperate ForestLife in Temperate Forest• Location

– Mid latitudes

• Description– Forest dominated by broad-

leaved hardwood trees that lose their foliage annually

– AKA – Deciduous forest• Temperature

– Has 4 seasons

• Rainfall– 70-150 cm/year

• Soil– Rich in humus + clay– Lots of vegetation

Life in Temperate ForestLife in Temperate Forest

• Plants

• Animals

maple

elm

Life in Rain ForestsLife in Rain Forests• Location

– near equator

– Occupy 6% of Earth’s surface

• Description– Extensive amounts of moisture

supplied by rainfall or by coastal clouds + fog

• Temperature– Avg temp 77 oF

• Rainfall– 50-260 inches/year

• Climate– Hot + humid (77-88%)

• Soil– Very poor at ground level

Life in Rain ForestsLife in Rain Forests• So Many Species Hypotheses:

– Since no “ICE AGE” in tropics, species were able to evolve + create more biodiversity

– Year-round warm temperature allows for ideal growing conditions for food supply for organisms

Vertical LayeringVertical Layering• Ground

– Dark, moist floor

– Leaves + organic matter

• Understory– Still air, humid, dark

– Low level vegetation (vines, epiphytes)

• Canopy– “living roof”

– Most of life found here

– Emergents (tall trees)

Life in Rain ForestLife in Rain Forest• Plants

• Animals

ferns

epiphytePalm tree