Ecology Intro and Population Ecology

  1. Ecology
    study of interactions of organisms with their biotic and abiotic environment
  2. Environmentalism
    social/political movement to raise concerns about environmental issues
  3. Population Ecology
    How many individuals live in a given area
  4. Community Ecology
    Species interactions' effects on community structure
  5. Ecosystem Ecology
    Energy flow and chemical cycling
  6. Landscape Ecology
    Exchanges between arrays of ecosystem
  7. Populations are characterized by
    • dispersion
    • growth
    • survivorship
    • age structure
  8. Dispersion
    Distribution in space and time
  9. Dispersion Dependent on Two Factors
    • Climate¬†
    • Geography
  10. Range
    geographical area in which a species can occur
  11. Growth
    Change in population size with time
  12. Growth is Dependent on
    • # of individuals in population to reproduce
    • capacity of organism to reproduce
    • availability of required resources
  13. Factors affecting rate of change in population size
    • reproductive capacity = r
    • # of reproductive individuals = N
  14. G = rN
    • "J-curve"
    • Unlimited Growth
  15. K
    Carrying Capacity
  16. Growth equation must reflect
    • reproduction of a population
    • Effect of carrying capacity K
  17. With carrying capacity, formula becomes
    G = rN [(K-N)/K]
  18. Limiting Factor
    single environmental factor that sets the carrying capacity
  19. When population exceeds carrying capacity, three outcomes are possible
    • population size drops to original K
    • excess individuals despoil environment, reducing K and population falls to new, lower K
    • Environmental stress causes population to crash to or near extinction
  20. Survivorship Patterns
    population life history patterns
  21. Three Basic Patterns of Survivorship
    • Type I - low infant mortality
    • Type II - constant mortality
    • type III - high infant mortality
  22. Two Types of Life Cycle Strategies
    • "Weedy"
    • "Stable"
  23. "Weedy"
    • many offspring with little or no parental input in raising
    • disperses widely¬†
    • Ex: weeds, oysters
  24. "Stable"
    • fewer offspring, much parental input in raising
    • disperse less widely- raised in stable environment
    • Ex: whales, humans, coconut palm
  25. Age Structure
    bar graph of # of individuals in various age classes
  26. Three Ecologically Relevant Age Classes
    • preproductive - too young to reproduce
    • reproductive - age of production
    • postreproductive - too old to reproduce
Card Set
Ecology Intro and Population Ecology