CH. 15 THE BIOSPHERE 1

CH. 15 THE BIOSPHERE 1

15.1 BIOSPHERE Part of Earth where life exists All of Earth s ecosystems Biota all living things in biosphere Abiotic factors NOT included Ex: water, air, rocks 2

EARTH S SYSTEMS 1) Biosphere 2) Hydrosphere water, ice, water vapor 3) Atmosphere the air around earth 4) Geosphere features of surface Continents, rocks, sea floor, all below surface 3

ECOSYSTEMS ARE LINKED Change in one sphere affects others Ex: What could result if plants are removed from a riverbank? How does this affect the other spheres? 4

GAIA HYPOTHESIS Proposed by James Lovelock United Kingdom Considers Earth itself a kind of living organism Recognizes connections and feedback loops between biotic and abiotic factors More CO 2 = more plants More plants = more O 2 More O 2 = few plants Cycle continues Earth is NOT a thinking being! 5

15.2 CLIMATE Prevailing weather of a region Includes: Ave temp Ave precipitation Relative humidity Seasonal variations 6

MICROCLIMATE Small, specific climate within a larger climate Very important to life Ex: hole in rotting log Grassy meadow Top of tree San Francisco 7

3 CLIMATE ZONES Ave temp and precipitation determine 1) polar 2) tropical 3) temperate 8

WHAT DETERMINES CLIMATE? Sun Air and water movement Landmasses 9

SUNLIGHT Rays most intense (thus hottest) where strikes directly Region near equator = most sun Polar regions = least sun Rays strike at lower angle/less intense Earth s axis More tilted away from sun = less light = colder 10

AIR AND WATER Movement caused by Sun when it heats Earth Warm = less dense Rises Cools as it rises; releases moisture Currents movement in water Connected to: Water temp Air movement Earth s rotation Salt levels 11

LANDMASSES Land heats up and cools more quickly that water Coastal areas = smaller changes in temperature Water evaporates faster from water than land Coastal areas = more humid and more precipitation Mountains air cools as it rises Side facing wind = wet Downside of wind = rain shadow area of decreased precipitation 12

ADAPTATIONS Organisms adapt to survive Ex: Frog p. 433 What enables it to survive so well? Polar bear? 13

15.3 BIOMES Characterized by climate and plants 6 major biomes Broad Can be divided more specifically Ice caps and mountains are NOT biomes 14

1) TROPICAL RAIN FOREST Warm temp Lots of precipitation Thick forests Limiting factor = Sunlight Little reaches ground <1% Infertile soil Canopy tops of trees Many animals Epiphyte plant that grows above ground (ex: on trees) 15

2) GRASSLAND 2 Types A)Tropical (Savannas) Africa, S. America, Australia Grasses 3-7 ft. tall Some shrubs Limiting factor = rainfall Rainy and dry season Hoofed animals dominate biome 16

2) GRASSLAND B)Temperate S. Africa, E. Europe, N. America 20-35 rain/snow per year Most in spring/early summer Dry and warm summers Many animals live below ground Fires are common Some seeds need fire to germinate 17

3) DESERT Very dry (arid) <10 precip per year Many nocturnal animals Plants = cacti-like or have deep roots 4 types 18

3) DESERT A) Hot >100 F Precip falls as rain B) Semiarid Temps rarely exceed 100 F C)Coastal 25-95 F D) Cold Precip mostly snow 19

4) TEMPERATE Distinguishable seasons 2 Types: A) Deciduous forest Trees drop leaves/go dormant 30-59 precip Spread evenly thru year Hot summer/cold winter 20

4) TEMPERATE B) Rain forest - Long wet season/short, dry summer >98 precip Evergreens dominate Coniferous retain needles all year 21

5) TAIGA = Boreal forest Cooler climates Cold, long winter Short, humid summers 12-33 precip per year Coniferous forest dominant 22

6) TUNDRA Subzero temps North latitudes Long winter < 5 precip Permafrost permanently frozen ground Barren Few plants and animals 23

MINOR BIOMES Ex: Chaparral (Mediterranean shrubland) Hot, dry summer Cool, moist winter Along S. CA coast 15-40 rain Read p. 438 24

POLAR ICE CAPS No soil No plant community Permanently frozen NOT a biome Ex: Antarctica, parts of Greenland, N. Pole 25

MOUNTAINS NOT a biome Rich biodiversity As elevation increases, life characteristics change Represents various biomes Ex: grassland at bottom Deciduous forest in middle Tundra at top 26

15.4 MARINE ECOSYSTEMS Oceans Separated into zones Use following abiotic conditions: Sunlight Temp Salinity Turbidity (murkiness) Depth Water Chemistry 27

OCEAN ZONES Dif systems used: 1) separates pelagic zone (open sea)from benthic zone (floor) 2) presence of light Photic zone vs. aphotic zone (depths) 3) 4 zones made using: Distance from shore Water depth 28

SYSTEM #3: 4 MAJOR ZONES 1) Intertidal land bw high and low tide Ex: Beach and tidal pools Variety of conditions Organisms must adapt 2)Neritic from intertidal to continental shelf Depth = few cm to >200m 29

SYSTEM #3: 4 MAJOR ZONES 3) Bathyal edge of neritic to base of continental shelf Greek = deep 200m to 2000m Turbid; lots of silt High pressure Burrowing animals thrive 30

SYSTEM #3: 4 MAJOR ZONES 4) Abyssal below 2000m Greek = bottomless Complete darkness Deep sea vents Support life Chemosynthetic organisms Base of food web Strange organisms Some make own light 31

NERITIC ZONE LIFE < 1/10 th of ocean 40x more biomass than rest of ocean Plankton tiny, free-floating organisms Includes: Zooplankton Animals Phytoplankton - photosynthetic protists Ex: algae Base of food chain Estimate produce up to 70% of all oxygen 32

COASTAL HABITATS Shallow waters of neritic zone Coral reefs tropical climate Mutualistic relationship w algae Algae = nutrients for reef Reef = home for algae Reef = mostly dead skeletons Support lots of life Over 400 dif species of coral Delicate Sensitive to pollution, temperature Artificial reefs Ex: shipwrecks 33

COASTAL HABITATS Kelp forests cold, nutrient-rich water = seaweed forests Grow up to ~100 ft High productivity Habitat: Ex: small invertebrates Sea lions Underwater Kelp Forests - YouTube [360p].mp4 34

15.5 FRESHWATER Estuary where river flows into ocean Salt and freshwater Partially enclosed Nutrient rich Tide changes water levels Highly productive ecosystem Comparable to rain forest and coral reef Contain lots of decomposers Home to many endangered species 35

ESTUARIES 75% of fish we eat depend on nurseries of the sea Fish spawn Young mature Birds migrate/layover here Threats: Humans Development Pollution Erosion Up to 80% have been lost in U.S. What's An Estuary_ Now You Know. - YouTube [360p].mp4 36

FRESHWATER Moving and standing water Wetlands standing water Very productive Help maintain clean water Filters and renews underground supply Ex: Bogs, marshes, swamps ID by plant communities 37

FRESHWATER Factors that affect life here ph Oxygen levels Water temp Water flow How would a tadpole in a pond differ from that in a fast moving river? 38

WATERSHED Region of land that drains into a body of water Where lakes, streams, and ponds originate 39

3 FRESHWATER ZONES Lakes and ponds Some may not have all 1) Littoral similar to intertidal Between high and low water marks on shoreline Well-lit Warm Shallow Diverse organisms: Invertebrates Water plants 40

3 FRESHWATER ZONES 2) Limnetic (pelagic) open water farther from shore Lots of plankton 3) Benthic - bottom Less sunlight Many decomposers 41

WATER TURN OVER Water differs in temp layers separated by thin zone called thermocline Water most dense at 39 F When reaches this temp, it sinks below other water whether warmer or colder Moving all year Mixes nutrients from bottom Planet Earth - Fresh Water HD - YouTube [360p].mp4 2:45 42