Chapter 39: Biomes

Biomes

Biomes

Major type of ecosystem charectorized by a specific climate or species composition.

Summer

hemisphere tilts toward the sun

winter

Hemisphere tilts away from sun

Equator

warm water evaporates, rises, and forms clouds, then rain = tropical rain forests

30°latitude

cool, dry air descends, absorbing moisture from the land deserts

60°latitude

warm air mass causes precipitation over the midlatitudes = temperate biomes

Tropical rain forest

-Climate: Warm and wet. -Plants/Animals: high species diversity. -destruction threatens indigenous people and global water and carbon cycles.

Temperate forest

-Climate: Warm summers, cool winters, consistent rainfall.

• Plant/Animals:Trees and migratory animals are common. -30°and 60° North latitude -large areas between 30°and 60° North latitude

Temperate deciduous forests

dominated by trees that shed their foliage in autumn,

temperate coniferous forests

mostly evergreen conifers that lose only a few leaves at a time.

Taiga (boreal forest)

-Climate: Cold and relatively dry. -Seasons: *long, harsh winter, >six months, -> growing season short. *Moisture can be scarce in winter, water remain frozen. -Plants: evergreen trees. -Animals: mammals and birds stay year-round.

Tropical savanna

-Climate: Warm year-round with wet and dry seasons -Plants: Trees or shrubs, Perennial grasses, Patches of drought- and fire-resistant trees and shrubs -Animals: Herds of grazing animals

Temperate grassland

-Climate: moderately moist -Seasons: hot summers and cold winters -Plants: few if any trees due to insufficient rainfall, grazing, and fire.Wind-pollinated grasses dominate this biome along with large grazing herbivores. -Animals: Grazing Herbavoirs

Desert

-Climate: All deserts—cold and hot—are dry -Location: 30° North and South latitudes -Soil low in organic matter -Plants: adapt to store water -Animals:Nocturnal animals

Mediterranean shrubland

-Seasons: Hot, dry summers and cool, moist winter suceptible to fire in summer -Plants: resistant to fire and are drought tollerant -Animals: Jack rabbits, mule deer, and coyote

Tundra

-Climate: Very Cold, Little moisture -Plants: permafrost > limits small plants -Animals: caribou and fox have very thick fur

Polar ice

-Climate: Extreamly cold, dry and windy -Plants: phytoplankton -Animals: Shared characteristicsin northern and southern

Northern ice cap

thin ice layer that covers the Arctic Ocean

Antarctica

southernmost continent is a landmass covered with a thick layer of ice.

Standing water

Lakes and ponds -primary producers: phytoplankton -consumers: Zooplankton and fish -bacteria common

photic zone

Light penetrates and where photosynthesis occurs

littoral zone

Part of photic zone shallow shoreline region where rooted plants occur

limnetic zone

Part of photic zone open water where light penetrates

profundal zone

Deep water where light does not penetrate.

benthic zone

the sediment at the bottom of standing water

oligotrophic

if they are nutrient-poor and have low productivity. The water is clear because phytoplankton aren’t abundant enough to cloud the water.

Eutrophic

surface water is nutrient-rich and has high productivity. The rich algal growth turns the water green and murky. A eutrophic lake eventually fills completely with sediments and transforms into a freshwater wetland

Streams

carry running water

Rivers

the largest streams.

Estuaries

nutrient-rich areas where a river meets an ocean. Organisms must tolerate extreme shifts in salinity.

Intertidal zones

area between high and low tide marks Organisms that inhabit these zones must be able to withstand both exposure to the atmosphere and being submerged in salt water.

Coral reefs

large underwater structures comprised of calcium carbonate built by coral animals

neritic zone

water between the coast and the edge of the continental shelf. abundant sunlight sediment contribute to nutrition -> high primary producers

oceanic zone

water beyond the continental shelf

continental shelf

an area that is sometimes dry land but is currently relatively shallow sea

Benthic Zone

Sediment at the bottom of the ocean

Pelagic Zone

All of the water above sea floor Photic zone and Profundal zone