ECOLOGY

1
ECOLOGY

• CH. 1 2

2
ECOLOGY

• Def the study of how living things interact
  with their environment
• Habitat where an organism gets the things it
  needs to survive
• Biotic Factors ? Living
• Abiotic Factors ? Non-living
• Levels of Organization
• Organism individual
• Population members of same species
• Species similar organisms that are capable of
  producing offspring that are similar to parents
• Community all the populations in an area
• Ecosystem the community plus non-living parts
  of the area
• Biosphere all the ecosystems of the world

3
Studying Populations

• Population number of individuals
• Population Density individuals/ unit of area
• How crowded it is
• Methods
• Direct Observation actually seeing
• Indirect Observation seeing evidence without
  seeing individuals
• Ex.
• Sampling average of smaller areas to estimate
  total population
• Mark and Recapture
• ( Marked X captured 2nd time)/ caught 2nd
  time with marks

4
Studying Populations

• Changes to population
• Birth rate vs. Death rate
• Immigration (in) vs. Emigration (exit)
• Limiting Factors environmental factors that
  prevent a population from increasing
• Ex.
• Carrying Capacity the maximum number of
  individuals an area can support
• Based on limiting factors

5
Interactions Among Populations

• Niche how an organism interacts and uses its
  habitat
• The role or job of an organism
• Adaptations Physical or behavioral
  characteristics that make an organism more likely
  to survive (better able to use habitat)
• Keeps niches different from other species
• Natural Selection survival of the fittest
• Forms adaptations
• Competition struggle for limited resources
• Hurts both species
• Interspecific two different species
• Ex.
• Intraspecific two members of same species
• Ex.

6
Interactions Among Populations

• Predation A specie hunts, kills, and eats
  another
• Predator Adaptations
• Prey Adaptations
• Mutualism Both species benefit (/)
• Commensalism One species benefit, the other is
  unaffected (/0)
• Parasitism one species (parasite) lives off
  from another (host) causing it harm
• Doesnt usually kill host

7
Energy Flow through an Ecosystem

• Food Chain ? single path
• Food Web ? many, interconnected food chains
• Trophic Levels
• Producer autotrophs
• Photosynthesis
• Consumer heterotrophs
• Primary consumer herbivores
• Secondary Consumer carnivore
• Omnivore sometimes primary, sometimes secondary
• 3rd level, 4th level etc.
• Scavengers carnivore that eats the already dead

8
Energy Flow through an Ecosystem

• Decomposers detritivores
• Almost all energy passes here last
• Exception stored energy in fossil fuels
• Energy Pyramid shows total amount of energy in
  each trophic level for an ecosystem
• Most energy in producers
• 10 is passed onto next trophic level
• Each trophic level has less individuals
• Not many top carnivores
• Limit to number of levels in food chain
• Biological Magnification a chemical (pollutant)
  becoming more concentrated as it is passed
  through the food chain
• DDT and Bald Eagles

9
MATTER CYCLES

• Hydrologic Water Cycle
• Evaporation liquid to gas (water vapor)
• Purifies only water goes up
• Transpiration trees/plants evaporating water
• Condensation water vapor to liquid
• Clouds fog
• Precipitation
• Rain, snow, sleet, hail, ice
• What happens next?
• Surface Run-off ditches ? streams ? lakes,
  rivers ? oceans
• Aquifer ground water
• Ends up in living organisms
• Evaporation returns directly to atmosphere

10
MATTER CYCLES

• Carbon Cycle
• Found in atmosphere as Carbon Dioxide (CO2)
• .03
• Linked to global warming as environmental concern
• Needed by organisms to form organic compounds
• Converted by plants through the process of
  photosynthesis
• Returned to atmosphere
• Respiration breaking down carbon compounds for
  energy
• Combustion burning fossil fuels or plant
  products
• Double Whammy! Deforestation
• Cant take carbon out
• Burning puts carbon in
• Fossil Fuels carbon stored deep in Earth
• Past organisms
• Oil, natural gas, coal

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MATTER CYCLES

• Nitrogen Cycle
• Found in the air as atmospheric nitrogen (N2)
• 78 of air most abundant substance
• Can NOT be used directly by most organisms
• Nitrogen fixation changing atmospheric nitrogen
  into a usable form
• Needed by organisms to make proteins
• Rhizobium (bacteria) or lightning
• Found on root nodules in Legumes (alfalfa,
  clover, beans)
• Atmospheric nitrogen is changed into ammonia
  (NH3) or nitrates (NO4)
• Can be added to soil through fertilizers or
  decomposition of organisms
• Denitrification changes nitrogen compounds back
  into atmospheric nitrogen by bacteria.

12
Succession

• Read Section 2-5 (p. 76-78)
• Read Silently
• Take a break after each section and ask, what
  did I just read?
• Write down Topics or Objectives you should be
  able to accomplish after reading
• Make a list of key terms and key ideas (these are
  the notes)
• Topics (Objectives)
• Know the definition of succession
• Know the difference between primary and secondary
  succession
• Know the order of change that occurs during
  succession
• Key Terms
• Succession, pioneer species, biome

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Succession

• Def the change of an ecosystem back to its
  climax community
• Climax community the natural state of an
  ecosystem
• Based on climate (weather, temp), altitude, soil
  etc.
• Biomes
• Pioneer species first to arrive after
  disturbance
• Lichens, weeds
• Animation
• Primary no pre-existing ecosystem
• Secondary return after disturbance
• Can be human or natural disturbances. ? ex