World Biomes and Marine Ecosystems

Chapter 32Elizabeth Pryal

Biomes

Terrestrial ecosystem- land-based relationship◦Organisms and nonliving components◦Also called biomes

Large terrestrial ecosystems covering wide geographic area

◦Nine major biomes Classified by temperature and precipitation

Tundra

One of the harshest environmentsLocated in the higher latitudesSupports northernmost limits of plant

growthMoss, lichen, hardy grasses, and small

shrubs19 percent of Earth’s land surface Northern Canada, Greenland, and

Northern Asia

Tundra (continued)

Average temperature is 10°FSoil classified as permafrost

◦Frozen throughout the year◦Top melts, forms small pools liquid water◦Principal source of water for organisms

Long, cold winters below freezing, little sunlight

Summer-50°F

Tundra(continued)

Considered arid◦Less than 10 inches precipitation each year

Large organisms◦Musk ox ◦Caribou◦Arctic fox◦Polar bear◦Arctic hare◦Humans

Coniferous Forests

Latitudes next to tundra- coniferous biome◦Also taiga or boreal forest◦Higher latitudes below tundra◦11 percent of Earth’s land surface◦Long, cold winters and short, hot summers◦Home to many cone-bearing species

Pine, spruce, and fir

Coniferous Forests (continued)

Precipitation 20 inches per yearSummer temperatures exceed 60°FMost of winter below freezingWide variety of animal species

◦Wolves◦Bears◦Squirrels◦Rabbits◦Moose◦Hawks◦Deer◦Humans

Temperate Forests

Adjacent to coniferous forests in middle latitudes

Temperatures- forest biome◦Deciduous forest where trees drop leaves

Maple, birch, ash, hickory, beech, and oak Annual color change of leaves

◦Long hot summers, cold winters◦High amount of precipitation, snow and rain

Temperate Forests (continued)

Average annual temperature 49°FMost of winter below freezingTemperature- forest covered with snow in

winterSummer temperature above 70°F

Grasslands

Grassland biome located near middle latitudes

Mostly in interior of continents Long, hot summers with periodic droughtsDuring droughts, lighting can cause

wildfiresPrevents larger plants from growingVegetation limited to grasses and shrubs

Grasslands (continued)

Less than 15 inches of rain/yearSupport large herds of animalsSupport much of world’s agriculture Bread basket grasslands of the

Midwestern United States

Savannas

Savanna biome- large amount of grassy vegetation

Known as tropical grassland- found near equator

Located in interior of continents- long rainy season

Rainfall averages 40 inches◦Less than 2 inches over a 2-month period

Savannas (continued)

Drought period reduces vegetation to:◦Tall grass, shrubs, and drought- resistant trees

Annual temperature fairly constant◦Average of 77°F

Serengeti Plain of Central Africa◦World’s most exotic animals◦Lions, giraffes, cheetahs, zebras, and elephants

Deserts

Desert biome- one of Earth’s harshest environments

Very little rainfall- less than 2 inches Located near interior of continents

◦Many different latitudesDry climate known as arid climateCold deserts also exist in higher and

middle latitudes

Deserts (continued)

Can be located at very high latitudes◦May be driest place on Earth

Desert in Andes Mountains of South AmericaDesert biome 30 percent of land surfaceDaytime- 100°F, nighttime- 40°FWide variety of organism needing little

water◦Cactus and animals such as kangaroo

Tropical Rain Forests

Tropical rain Forest biome is the most productive ecosystem

Greatest amount of biological diversityLocated near equator in tropics High amounts of rainfall12 hours of sunlight each dayRapid-growth plants supporting variety of

animals

Tropical Rain Forests (continued)

Rainfall approximately 110 inches/yearMaintains stable temperature of 77°FTrees are broad-leafed evergreensApproximately 2 percent of Earth’s land

surface◦Central America, South America, Africa,

Southeast AsiaHome to more than 70 percent of species

on Earth

Chaparral

Chaparral biome◦Warm coastal climate◦Cool, rainy winters and hot, dry summers◦Primary vegetation

Shrubs, grasses, and drought-resistant trees◦Coast of Mediterranean Sea and Southern

California◦Experiences periodic wildfires

Mountains

Mountain biome◦Same attributes as coniferous forest biome and tundraExtreme temperature caused by forest not

latitudes Anywhere there are extremely high mountainsConiferous trees at lower altitudesGive way to tundra vegetation higher altitudesLocated near equator- high mountain elevations

Coastal Wetlands

Oceans cover 71 percent of Earth’s surface

Land covered by lakes, rivers, and wetlands

Aquatic ecosystems support variety of living organisms

Marine ecosystem-within the ocean◦Classified by location within ocean

Coastal Wetlands (continued)

Coastal wetlands-where land meets sea◦Coastal marine breeding grounds◦Bays, salt marshes, lagoons, and mudflats◦Partially covered by saltwater throughout year◦3 percent of all wetlands

The Neritic and Intertidal Zones

Neritic zone-intertidal zone◦Along the coasts-begins at shoreline◦Experience high and low tides◦Organisms Include:

Mussels, hermit crabs, starfish, seaweeds Sea anemones, algae, and barnacles

◦Harsh because of tides, waves, and tidal forces

Oceanic Zone

Second ecosystem in open oceanStarts at a depth of 600 feetTwo main life-forms plankton and nektonPlankton-free-floating organisms drift with

currentsInclude microscopic algae called

phytoplanktonSingle-celled Zoo plankton

Oceanic Zone (continued)

Nekton◦Marine organism that move under their own

power◦Include fish, squid, octopus, whales, and

dolphins◦Live at all depths of ocean◦Some live in ocean and in freshwater

Hydrothermal Vent Communities

Extremely deep and dark water of oceansHydrothermal vent-chimney-like structure

spewing hot water◦Rich in minerals◦Temperatures more than 600°F◦Caused by volcanic activity◦Water seeps into cracks and is superheated

Hydrothermal Vent Communities (continued)

First discovered near equator to Pacific Ocean

Depth of 8,000 feet in total darknessLarge tube worms 3 feet longLarge mussels and white crabsWater exceeding 200°FPressure exceeding 5,000 pounds per

square inch

World Biomes and Marine Ecosystems

Chapter 32