Populations by ert554898

VIEWS: 6 PAGES: 70

									P OPULATIONS
H OW POPULATIONS GROW
                                                    G OAL 1
A.   Give an example of something that is NOT a population and explain
     why it doesn’t count.

B.   Critique which of the following affects a population the most:
     i.     High density

     ii.    Inverted age-structure

     iii.   1 acre geographic range

     iv.    Negative growth rate

C.   Draw and describe when exponential and logistic growth occurs.

D.   Draw a logistic growth graph and label: “exponential growth”,
     “carrying capacity”, “positive growth”
    W HAT          IS A      P OPULATION ?

   Fish in Lake Superior?

   Crows in Alaska?

   Penguins in the Sahara Desert?

   Birds in Minnesota?

   All individuals of a species that live together in
    one place at one time
    F EATURES OF A P OPULATION
                 #1 - Size

   Population Size
       Natality rate

       Mortality rate

       Immigration

       Emigration

   How does each affect a population?
    F EATURES OF A P OPULATION
                  #1 - Size

   Geographic Range
       Bacteria = 1 cubic meter

       Hydrilla = every continent except Antarctica

   Growth rate

   Age structure
       Number of males/females at each age

       Why?
       F EATURES OF A P OPULATION
                #2 - Density
Population Density
      Number of individuals in a given area

      Lower density = less chance of reproduction
       F EATURES OF A P OPULATION
             #3 - Dispersion
Population Dispersion
      How individuals are arranged space
          Randomly
          Evenly spaced
          Clustered
T YPES OF
P OPULATION G ROWTH
 Exponential

     Growth
    Rate of growth stays the
     same
        exponential growth curve
         (J-shaped curve)
        population size increases
         steadily
   Exponential growth cannot be sustained
       Population grows- resources eventually become depleted



   Population growth slows



   Populations reach carrying capacity
       C ARRYING C APACITY

Population
                  Determined by limiting factors:

                      Food

size that an          Water

environment           Shelter


 can sustain
                      Space

                      Mate choice

                      Weather

                      Disease

                      Pollution
L OGISTIC M ODEL
    Below carrying
     capacity - birth rate
     is rapid
    Approaching
     carrying capacity
        birth rate slows, death
         rate increases
        competition for
         resources tends to
         increase

    RATE of Growth
     SLOWS (S-shaped curve)
     5.2 L IMITS                 TO         G ROWTH

   Limiting Factors – things that control the size of a
    population
       Density dependent
           Higher density = increased affect

       Density independent
           Affects regardless of density
D ENSITY DEPENDENT OR
         INDEPENDENT ?
D ENSITY DEPENDENT OR
         INDEPENDENT ?
D ENSITY DEPENDENT OR
         INDEPENDENT ?
D ENSITY DEPENDENT OR
         INDEPENDENT ?
D ENSITY DEPENDENT OR
         INDEPENDENT ?
D ENSITY DEPENDENT OR
         INDEPENDENT ?
D ENSITY DEPENDENT OR
         INDEPENDENT ?
D ENSITY DEPENDENT OR
         INDEPENDENT ?
D ENSITY DEPENDENT OR
         INDEPENDENT ?
D ENSITY DEPENDENT OR
         INDEPENDENT ?
G RAPH M ANIA !
 1. W HICH GRAPH REGION ( S )
SHOW EXPONENTIAL GROWTH ?
  2. W HICH GRAPH REGION ( S )
SHOW LARGER BIRTH RATE THAN
                DEATH RATE ?
  3. W HICH GRAPH REGIONS
COMBINE TO SHOW A LOGISTIC
                   CURVE ?
  4. W HICH GRAPH REGION ( S )
SHOW EQUAL BIRTH AND DEATH
                     RATE ?
5. W HICH REGION ( S ) SHOW A
    NEGATIVE GROWTH RATE ?
7. W HAT SHAPE GRAPH IS
                  THIS ?
        8. U NDER WHAT
 CIRCUMSTANCES CAN THIS
TYPE OF GROWTH OCCUR ?
9. W HAT TYPE OF GRAPH IS
                    THIS ?
10. W HAT DOES “M”
         REPRESENT ?
11. W HAT DEFINES WHERE
        “M” IS LOCATED ?
12. W HAT WOULD THE Y - AXIS
                 LABEL BE ?
        13. W HAT WAS THE ~
TEMPERATURE CHANGE BETWEEN
             1920 AND 2000
    14. W HAT IS THE BASIC
CONCLUSION OF THIS GRAPH ?
15. H YPOTHESIZE WHAT THIS
 GRAPH WOULD LOOK LIKE IF
        EXTENDED 100 YRS
16. H OW COULD THIS GRAPH
           BE MISLEADING ?
17. T HE BASIC POINT OF THIS
                GRAPH IS ….?
 18. H OW ARE CFC’ S
CONNECTED TO GLOBAL
           WARMING ?
19. B ECAUSE OF CFC’ S ,
    LEVELS OF WHAT HAS
  INCREASED ON E ARTH ?
20. W HAT KINDS OF THINGS
    WERE CFC S USED FOR ?
21. ~ WHAT YEAR DID EXPONENTIAL
                 GROWTH BEGIN ?
  22. W HAT CONTRIBUTED TO HUMANS
NOT GROWING EXPONENTIALLY SOONER ?
23. D O YOU THINK WE WILL REACH 13
      BILLION PEOPLE BY 2039? W HY ?
24. I F WE REACH 13 BILLION BY 2039 AND
CONT. CURRENT GROWTH RATE OF DOUBLING
    EVERY 40 YEARS , HOW LARGE WILL THE
          WORLD POPULATION BE IN 2119?
25. W HAT TYPE OF GROWTH DOES THIS
                  GRAPH REPRESENT ?
 26. W HAT ISSUES DO YOU PERCEIVE
WITH THIS CURRENT GROWTH TREND ?
I SLAND R OYALE
S UPER - IMPOSED – P 139
                                    G OAL 2

A.   How has the human population grown and
     transitioned?

B.   What impact do we have on our planet?
        Sustainability

        Renewable/nonrenewable

        Pollution

        Biodiversity
    CH 5.3-H UMAN P OPULATION G ROWTH
   Demography –study of human populations
   As civilization advanced, population growth increased
       What has limited human population growth throughout history?

   Lower death rate caused exponential growth
   World population continues to increase, but growth rate has
    started to decrease
       Give an example of a rate




             4/7/2012
                D EMOGRAPHIC T RANSITION
   Dramatic change from high birthrates & death rates to low
    birthrates & death rates
   Three stages (shown below)
       (US, Japan, & Europe have completed)
       (S. America, Africa & Asia are in stage II)




             4/7/2012
     A GE S TRUCTURE & G ROWTH




•Slow & steady growth   •Population predicted to
predicted               double in next 30 years
                                              4/7/2012
4/7/2012
     CH 6.1-E FFECT OF H UMAN A CTIVITY
   Question: What happens when a growing
    human population does not adequately
    manage natural resources that are both vital
    and limited?




                                              4/7/2012
             E COSYSTEM G OODS &
                        S ERVICES
   Renewable resource -can be produced
    or replaced by an ecosystem
    -trees, wind
   Nonrenewable resource –cannot be
    replaced in a reasonable amount of
    time
    -fossil fuels
   Sustainable development - Using
    resources without causing long-term
    harm

                                          4/7/2012
                                               S OIL

                          Deforestation
Desertification              Takes nutrients out of soil


   Farmland  Desert
                          Contour farming
       Loss of topsoil
                              Farming parallel to land’s
       Dry                    contour to reduce erosion

       Overgrazing

       Erosion
                           WATER

   Lack of freshwater
       Ogallala aquifer

   Water pollution
        B IOLOGICAL M AGNIFICATION
   Occurs when pollutants
    are taken in by an
    organism and not broken
    down.
   Increase in concentration
    as you move up trophic
    levels.
   Examples:
    -DDT (insecticide)
    - mercury
    -lead                        4/7/2012
   Smog                       A IR
       Chemical reaction of
        pollution with air

   Acid Rain
       Sulfur and Nitrogen
        pollution combining with
        water                            Greenhouse Gasses
                                             Carbon Dioxide and
   Particulates
                                              Water Vapor
       Ash or dust
                                             http://www.youtube.com
   Ozone                                     /watch?v=2taViFH_6_Y

       CFC’s
                     CH 6.3-B IODIVERSITY
   Biodiversity – all variation in all organisms
    -vital to the survival and evolution of species
    Three levels:
1. Ecosystem diversity –variety of habitats and
   processes in area
2. Species diversity - # of different species in area
3. Genetic diversity –all different DNA within a species
   or biosphere


                                                        4/7/2012
                  T HREATS TO B IODIVERSITY
   Human activity causes lower
    biodiversity
   As diversity decreases, risk of
    extinction increases.
Humans:
   Alter habitats
   Hunt
   Introduce invasive species
   Release pollutants

                                        4/7/2012
                  C ONSERVING B IODIVERSITY
   Ecological hot spot – a place where significant numbers of species and
    habitats are in immediate danger of extinction.




             4/7/2012
E COLOGICAL F OOTPRINT
               Land and water needed to
                support an organism or
                population

                   Resources
                       Food, water, energy,
                        shelter

                   Waste
                       Air and water
                        pollution
                                             C ONCEPT             MAP
 Connect the following   words.    Extinction
 Label the link between each.
                                    Invasive Species
 Habitat destruction
                                    Human population growth
 Biological magnification
                                    Water pollution
 Human activity
                                    Deforestation
 Endangered
                                    Chlorofluorocarbons (CFCs)
 Air Pollution

 Food Web                          Ozone

 Climate Change                    Mercury

 Desertification                   Acid Rain

 Overgrazing

                                                                   4/7/2012

								
To top