51 HOW POPULATIONS GROW

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CHAPTER 5

• 5-1 HOW POPULATIONS GROW
• 5-2 LIMITS TO GROWTH
• 5-3 HUMAN POPULATION GROWTH

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CHARACTERISTICS OF POPULATIONS

• GEOGRAPHIC DISTRIBUTION AREA WHERE POPULATION
  LIVES
• DENSITY - OF INDIVIDUALS IN SPECIFIC AREA
• GROWTH RATE DEPENDS ON OF BIRTH, OF DEATHS,
  MEMBERS COMING IN AND OUT

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FOOD CHAIN
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FACTORS AFFECTING POPULATIONS

• OF BIRTHS
• OF DEATHS
• OF INDIVIDUALS THAT ENTER OR LEAVE
• IMMIGRATION INDIVIDUALS ENTERING A POPULATION
• EMIGRATION NUMBER OF INDIVDUALS LEAVING A
  POPULATION

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KING PENGUIN POPULATION IS GROWING DUE TO OF
INCREASING BIRTHS
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LIMITING FACTORS

• FACTOR THAT CAUSE A POPULATION GROWTH TO DECREASE
• COMPETITION
• PREDATION
• DISEASE AND PARASITES
• CLIMATE EXTREMES
• HUMAN DISTURBANCES

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POPULATION SIZE
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GRAY WOLF POPULATION

• IN 1973 ONLY ABOUT 400 GRAY WOLVES EXISTED
• ENDANGERED SPECIES ACT PROTECTED THEM
• 2002, WE NOW HAVE OVER 4000

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AGE STRUCTURE DIAGRAMS

• SHOW POPULATION OF A COUNTRY BROKEN DOWN BY AGE
  AND GENDER
• http//www.pbs.org/wgbh/nova/worldbalance/numb-fla
  sh.html

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AGE STRUCTURE DIAGRAMS
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CHAPTER 6HUMANS IN THE BIOSPHERE

• 6-2 RENEWABLE AND NONRENEWABLE RESOURCES
• 6-3 BIODIVERSITY

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WHAT ARE RESOURCES?

• RENEWABLE RESOURCES ARE
• RESOURCES THAT CAN BE REPLENISHED
• EX GRASS, TREES, FRESH WATER
• NONRENEWABLE RESOURCES ARE
• CANNOT BE REPLENISHED BY NATURAL PROCESSES
• - EX COAL, OIL, NATURAL GAS

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• HUMAN ACTIVITIES CAN AFFECT THE QUALITY AND
  SUPPLY OF RENEWABLE RESOURCES SUCH AS LAND,
  FORESTS, FISHERIES, AIR, AND FRESH WATER

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EXAMPLES

• LAND RESOURCES - SOIL CAN BE PERMANENTLY DAMAGED
  IF MISMANAGED, PLOWING, SOIL EROSION,
  OVERGRAZING, AND DROUGHT

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EXAMPLES

• FOREST RESOURCES DEFORESTATION LOSS OF FORESTS
  CAN LEAD TO SEVERE EROSION AS SOIL IS EXPOSED TO
  HEAVY RAINS. SOIL CAN CHANGE AND PREVENT THE
  REGROWTH OF TREES.

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EXAMPLES

• FISHERY RESOURCES OVERFISHING

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EXAMPLES

• AIR RESOURCES
• - SMOG CAUSED BY CAR EXHAUST AND INDUSTRIES
• - POLLUTANTS RELEASED INTO THE AIR BY FOSSIL
  FUELS

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EXAMPLES

• FRESHWATER RESOURCES
• -POLLUTING STREAMS AND RIVERS
• -WASTE AND FERTILIZERS ON LAND CAN SEEP THROUGH
  SOIL

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HOW DO YOU FIX IT?

• LAND
• CONTOUR PLOWING
• LEAVING STEMS AND ROOTS FROM LAST YEARS CROPS
• FOREST
• REPLANTING
• GROWING GENETICALLY ENGINEERING CROPS

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HOW DO YOU FIX IT?

• FISHERY
• GUIDELINES SET BY US FISHERIES SERVICE REGULATE
  HOW MANY, WHAT SIZE AND WHERE
• AQUACULTURE RAISING OF ANIMALS FOR CONSUMPTION

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HOW DO YOU FIX IT?

• AIR
• WALK, DONT DRIVE
• CARPOOL
• CAR INSPECTIONS
• WATER
• CONSERVING WATER
• DRIP IRRIGATION

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BIODIVERSITY

• ONE OF THE EARTHS GREATEST NATURAL RESOURCES
• MANY DIFFERENT SPECIES PROVIDE US WITH FOOD,
  PRODUCTS, MEDICINE
• EXAMPLES PAIN KILLERS, ANTIBIOTICS, HEART
  DRUGS, ANTICANCER, ANTIDEPRESSANTS

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THREATS TO BIODIVERSITY

• ALTERING HABITATS
• HUNTING SPECIES TO EXTINCTION
• INTRODUCING TOXINS INTO FOOD WEBS
• INTRODUCING FOREIGN SPECIES INTO NEW ENVIRONMENTS