Ecology & the Biosphere Chapter 18. Biomes Major terrestrial or aquatic life zone Aquatic biomes...
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Transcript of Ecology & the Biosphere Chapter 18. Biomes Major terrestrial or aquatic life zone Aquatic biomes...
Ecology & the BiosphereEcology & the Biosphere
Chapter 18Chapter 18
BiomesBiomes
• Major terrestrial or aquatic life zone
• Aquatic biomes– Occupy roughly 75% of Earth’s surface – Freshwater– Marine
• Terrestrial biomes– Classified based on vegetation type
Aquatic - FreshwaterAquatic - Freshwater• Typically have a salt concentration of less than 1% • Standing water
– includes lakes and ponds
• Flowing water– rivers and streams
• Wetlands• Cover less than 1% of Earth • Contain a mere 0.01% of its water • Harbor about 6% of all described species• Are used for drinking water, crop irrigation, sanitation, and
industry
Aphoticzone
Photiczone
Benthic realm
Aquatic - MarineAquatic - Marine
• Typically have a salt concentration around 3%
• Oceans• Intertidal zones• Coral reefs• Estuaries
High tide
Benthic realm(seafloor from continentalshelf to deep-sea bottom)
Pelagic realm (open water) Low tide
Oarweed (to 2 m) Sea star
(to 33 cm)
Intertidalzone
Continentalshelf
Sea pen(to 45 cm)
Sea spider(1–90 cm)
Brittlestar
(to 60 cm) Glass sponge
(to 1.8 m)
Sponges(1 cm–1 m)
Brain coral(to 1.8 m) Phyto-
planktonZoo-
plankton
Man-of-war(to 50 m long)
Blue shark (to 2 m)
Sperm whale(10–20 cm)
Hatchet fish(2–60 cm)
Rat-tail fish(to 80 cm)
Octopus(to 10 m)
Gulper eel(to 180 cm)
Turtle(60–180 cm)
Sea cucumber (to 40 cm)
Tripod fish (to 30 cm)
Anglerfish(45 cm–2 m)
Photiczone
Aphoticzone
6,000–10,000 m
1,000–4,000 m
200 m
No light
“Twilight”
TerrestrialTerrestrial• Tropical Forest• Savanna• Desert• Chaparral• Temperate Grassland• Temperate broadleaf forest• Coniferous forest• Tundra• Polar ice
Temperate broadleaf forestConiferous forestArctic tundraHigh mountains (coniferous forest andalpine tundra)Polar ice
Tropical forest
Temperate grasslandChaparralDesertSavanna
Key
Tropic of Capricorn
30º N
Equator
30º S
Tropic of Cancer
Figure 18.27
Tropical Rainforest Tropical Rainforest
• occur in equatorial areas
• temperature is warm• days are 11–12 hours
long year-round• 200-400 cm rain
– 79-157 inches
SavannasSavannas
• dominated by grasses and scattered trees
• warm year-round• Experience 30-50 cm
rainfall – 12–20 inches – dramatic seasonal
variation
DesertsDeserts
• driest of all biomes• Less than 30 cm
– 12 inches
• May be very hot or very cold– 140 to -22 F
Temperate GrasslandsTemperate Grasslands• mostly treeless• 25-75 cm rain per
year– 10–30 inches
• Experience frequent droughts and fires
• characterized by grazers including bison and pronghorn in North America
Temperate Broadleaf ForestTemperate Broadleaf Forest
• Occurs throughout midlatitudes – sufficient moisture to
support the growth of large trees
• 75-150 cm rain – 30-60 inches
• Includes dense stands of deciduous trees in the Northern Hemisphere
Coniferous ForestConiferous Forest
• “Temperate rainforest”• dominated by cone-
bearing evergreen trees
• Includes the taiga– largest terrestrial biome
on Earth
TundraTundra
• Covers expansive areas of the Arctic between the taiga and polar ice
• characterized by– Permafrost
• permanently frozen subsoil
– Bitterly cold temperatures– High winds
Polar icePolar ice
• high latitudes – north of the arctic
tundra in the northern hemisphere
– Antarctica in the southern hemisphere
• Only a small portion of these land masses is free of ice or snow– Even in summer!